Piscium Catalogus OTOLITHI PISCIUM 2 Edited by Dr. Friedrich H. PFEIL Werner SCHWARZHANS A comparative morphological treatise of recent and fossil otoliths of the order Pleuronectiformes Piscium Catalogus A continuing file of all recent and fossil fishes from a paleoichthyological point of view Edited by Dr. Friedrich H. PFEIL, München Part OTOLITHI PISCIUM Volume 2 Werner SCHWARZHANS A comparative morphological treatise of recent and fossil otoliths of the order Pleuronectiformes Verlag Dr. Friedrich Pfeil München, April 1999 ISSN 0724-9012 ISBN 3-931516-54-7 Die Deutsche Bibliothek - CIP-Einheitsaufnahme Schwarzhans, Werner: A comparative morphological treatise of recent and fossil otoliths of the order Pleuronectiformes / Werner Schwarzhans. - München : Pfeil, 1999 (Piscium catalogus : Pt. Otolithi piscium ; Vol. 2 ISBN 3-931516-54-7 Orders, manuscripts and commentaries should be addressed to Redaktion PISCIUM CATALOGUS Verlag Dr. Friedrich Pfeil P.O. Box 65 00 86, D-81214 München Tel. (089) 74 28 270 • Fax (089) 72 42 772 • E-Mail 100417.1722@compuserve.com Gedruckt mit Unterstützung der Deutschen Forschungsgemeinschaft Copyright © 1999 by Verlag Dr. Friedrich Pfeil, München Alle Rechte vorbehalten – All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying or otherwise, without the prior permission of the copyright owner. Applications for such permission, with a statement of the purpose and extent of the reproduction, should be addressed to the Publisher, Verlag Dr. Friedrich Pfeil, P.O. Box 65 00 86, D-81214 München. Druckvorstufe: Verlag Dr. Friedrich Pfeil, München CTP-Druck: grafik + druck GmbH Peter Pöllinger, München Buchbinder: Thomas, Augsburg ISSN 0724-9012 Printed in Germany – Gedruckt auf chlorfrei gebleichtem und alterungsbeständigem Papier – Verlag Dr. Friedrich Pfeil, P.O. Box 65 00 86, D-81214 München Tel. (089) 74 28 270 • Fax (089) 72 42 772 • E-Mail 100417.1722@compuserve.com 3 Piscium Catalogus: Part Otolithi piscium, Vol. 2, pp. 1-391, 1021 figs., April 1999  1999 by Verlag Dr. Friedrich Pfeil, München, FRG – ISSN 0724-9012 A comparative morphological treatise of recent and fossil otoliths of the order Pleuronectiformes by Werner Schwarzhans * Abstract The following morphological study of otoliths of the order Pleuronectiformes (flatfishes) is the second part of a long term catalogue project mainly dealing with recent otoliths. Amongst teleost groups of comparable size, the otoliths of the order Pleuronectiformes are amongst the least well known. They are also not the easiest to work with morphologically and have never been subject of a comprehensive analysis. Taxonomic work with pleuronectiform otoliths is somewhat hampered by the often high degree of intraspecific variability, the low level of interspecific morphological differentiation and of course the ubiquitous effects of asymmetry. For this treatise I have investigated otoliths of more than 300 recent species of the Pleuronectiformes (corresponding to more than 50 % of the known recent species of the order) covering 116 genera of the 133 currently recognized. In addition, the 124 nominal fossil otolith species of the Pleuronectiformes and 47 recent species that have also been described from fossil otoliths are being revised. For this revision I have investigated otoliths of the majority of the nominal fossil species, mostly including type-material. The results of other important revisions recently made have been incorporated. As a result of this revision, 26 species are removed from the Pleuronectiformes, 60 fossil species and 35 recent species recorded as fossils are regarded as valid. 18 species are described as new: genus aff. Rhombocitharus novaezeelandiae, genus aff. Brachypleura xenosulcis, Pseudorhombus weinfurteri, Cyclopsetta transitus, Syacium dominicensis, Etropus concaviventris, Grammatobothus awamoaensis, Grammatobothus radwanskae, Arnoglossus grenfelli, Arnoglossus quadratus, Caulopsetta arnoglossoides, Laeops rharbensis, Samaris validus, Microchirus wienrichi, Quenselia cornuta, Pseudopardachirolithus nolfi, Peltorhamphus flexodorsalis, Cynoglossus obliqueventralis. 3 new fossil genera are established, all in the family Soleidae: Granulithus, Praeachirolithus and Pseudopardachirolithus. The phylogenetic interpretations and conclusions from the character-analysis of the otolithmorphology are being discussed and compared to published ichthyological analyses. As a result of this several systematical reallocations within the Pleuronectiformes are being proposed. This includes: 1. The separation of the genera Tephrinectes, Paralichthodes and of the Ammotretis Group from their traditional allocations to a position near the Citharidae (as early pleuronectiform off springs). 2. Upgrading of the Brachypleuridae to a separate family next to the Citharidae. 3. Reallocation of the genus Azygopus from the Rhombosoleinae (sensu NORMAN, 1934) to the Samarinae. 4. Reallocation of the genus Peltorhamphus from the Pleuronectidae (Rhombosoleinae; sensu NORMAN 1934) to the Soleidae. 5. Reduction of the Rhombosoleinae (sensu NORMAN, 1934) to include only the two genera Pelotretis and Rhombosolea. * Dr. Werner SCHWARZHANS, Ahrensburger Weg 103, D-22359 Hamburg, Deutschland. E-mail: WWSchwarz@aol.com Piscium Catalogus, Part Otolithi piscium, Vol. 2 4 Possible relationships are being discussed between the various genera in the Bothidae, Pleuronectidae and Soleidae as well as between the two families Soleidae and Cynoglossidae. The descriptions and figures of the pleuronectiform otoliths are arranged in 40 informal “genus groups”, distributed through 8 families and one group of genera of uncertain relationship, reflecting the results of the otolith analyses. This arrangement is not meant to represent a new formal subclassification of the order Pleuronectiformes. With this second volume (as with the previous one) in the newly established Otolithi Piscium Catalogus format, I have put great emphasis on large and, I hope, clear and detailed drawings. Whenever possible, I tried to figure more than just one specimen of each species to document intraspecific variability, morphological asymmetry when and where it occurs and ontogenetic changes in morphology. Due to the nature of the flatfishes, special emphasis is paid to side dimorphism of their otoliths, which is reflected in depicting otoliths of both sides of the fishes as far as this was achievable. With this monograph I hope to fulfill the following main objective: Present as many as possible detailed figures of recent and fossil pleuronectiform otoliths and thereby create a comprehensive basis for identification and correlation of otoliths for this order. Kurzfassung Im Rahmen einer langfristig angelegten systematischen Bearbeitung vorwiegend rezenter Otolithen befaßt sich diese Studie mit denjenigen der Ordnung Pleuronectiformes (Plattfische). Im Vergleich zu anderen TeleosteerGruppen gehören die Otolithen der Pleuronectiformes zu den weniger gut bekannten und waren auch bisher nie Gegenstand einer umfassenden morphologischen Analyse gewesen. Bedingt durch den oft hohen Grad intraspezifischer Variabilität bei ebenso oft geringen morphologischen Unterschieden zwischen verwandten Arten und die für Plattfische typische Asymmetrie, die auch bei Otolithen zu beobachten ist, gehört die taxonomische Arbeit mit Otolithen der Pleuronectiformes zu den komplizierteren innerhalb der Teleosteer. Für diese Arbeit lagen Otolithen von mehr als 300 rezenten Arten (mehr als 50 % der Pleuronectiformes) zur Untersuchung vor und zwar Vertreter von 116 der gegenwärtig 133 als valide angesehenen Gattungen. Die 124 beschriebenen fossilen Otolithen-Arten der Pleuronectiformes und 47 rezente Arten, die auch paläontologisch nachgewiesen wurden, wurden überwiegend auf der Basis eingesehenen Typ-Materials unter Hinzuziehung neuerer Bearbeitungen revidiert. Die Revision erbrachte , daß 26 Arten keine Pleuronectiformes sind. Von den verbleibenden werden 60 fossile Arten und 35 fossile Nachweise rezenter Arten als valide angesehen. Darin enthalten sind 18 neue Arten: genus aff. Rhombocitharus novaezeelandiae, genus aff. Brachypleura xenosulcis, Pseudorhombus weinfurteri, Cyclopsetta transitus, Syacium dominicensis, Etropus concaviventris, Grammatobothus awamoaensis, Grammatobothus radwanskae, Arnoglossus grenfelli, Arnoglossus quadratus, Caulopsetta arnoglossoides, Laeops rharbensis, Samaris validus, Microchirus wienrichi, Quenselia cornuta, Pseudopardachirolithus nolfi, Peltorhamphus flexodorsalis, Cynoglossus obliqueventralis. Es werden drei neue fossile Gattungen basierend auf Otolithen in der Familie Soleidae aufgestellt: Granulithus, Praeachirolithus und Pseudopardachirolithus. Die sich aus der morphologischen Charakter-Analyse der Otolithen ergebenden phylogenetischen Interpretationen werden mit entsprechenden ichthyologischen Analysen verglichen. Als Ergebnis davon werden einzelne systematische Umstellungen zur Diskussion vorgeschlagen, wie: 1. Abtrennung der Gattungen Tephrinectes, Paralichthodes und der Ammotretis Gruppe in eigene, früh phylogenetisch auf dem Niveau der Cithariden abgespaltene Gruppen. 2. Aufwertung der Brachypleuridae als familie neben den Citharidae. 3. Umstellung der Gattung Azygopus von der Unterfamilie Rhombosoleinae (sensu NORMAN, 1934) zur Unterfamilie Samarinae. 4. Umstellung der Gattung Peltorhamphus von den Pleuronectidae (Unterfamilie Rhombosoleinae; sensu NORMAN, 1934) zur Familie Soleidae. 5. Reduzierung der Rhombosoleinae (sensu NORMAN, 1934) auf die beiden Gattungen Pelotretis und Rhombosolea. Des weiteren werden auf Otolithen-Analyse basierende mögliche generische Verwandtschaften in den Familien Bothidae, Pleuronectidae und Soleidae sowie mögliche phylogenetische Verbindungen zwischen den Familien Soleidae und Cynoglossidae ausführlich diskutiert. Die systematische Gliederung der Otolithen-Beschreibungen und Abbildungen folgt einer informellen, nomenklatorisch unverbindlichen Gliederung in 40 “Gattungs-Gruppen” aufgeteilt auf 8 Familien und eine Einheit von Gattungen problematischer Zuordnung. In diesem zweiten Band der Otolithi Piscium Catalogus Reihe habe ich, ähnlich wie im ersten Band, Wert auf große und, wie ich hoffe, klare und detaillierte Zeichnungen gelegt. Wenn immer möglich werden mehrere Exemplare einer Art gezeigt, um intraspezifische Variabilität, ontogenetische Veränderungen und Seitendimorphismus zu verdeutlichen. Seitendimorphismus, auch bei Otolithen, ist eine “Spezialität” der Plattfische und dem wird, soweit möglich, mit der Abbildung von Otolithen beider Seiten des Fisches Rechnung getragen. Mit dieser Monographie hoffe ich eine Bestimmungs- und Bearbeitungsgrundlage für die Otolithen der Pleuronectiformes geschaffen zu haben. Schwarzhans: Pleuronectiformes 5 Table of contents 1. Introduction and Acknowledgements ............................................................................................................ 5 2. Catalogue of investigated material ................................................................................................................. 9 3. Distribution of recent Pleuronectiformes ....................................................................................................... 10 4. Fossil Pleuronectiformes otoliths ..................................................................................................................... 4.1 Systematics of fossil Pleuronectiformes otoliths ................................................................................ 4.2 Revision of fossil Pleuronectiformes otoliths ...................................................................................... 4.3 Distribution of fossil Pleuronectiformes faunas ................................................................................. 4.3.1 North and Middle America ...................................................................................................... 4.3.2 Europe .......................................................................................................................................... 4.3.3 NW-Africa ................................................................................................................................... 4.3.4 Indo-Pacific .................................................................................................................................. 4.3.5 New Zealand .............................................................................................................................. 12 12 14 22 22 22 26 26 27 5. Phylogenetic usage of Pleuronectiformes otoliths ........................................................................................ 5.1 Characterization of Pleuronectiformes otoliths .................................................................................. 5.2 The origin of the Pleuronectiformes and their outgroup relationship ........................................... 5.3 Pleuronectiform ”grouping” according to their otolith morphology .............................................. 5.3.1 Evolutionary trends in pleuronectiform otolith morphologies .......................................... 5.3.2 Definition of suborders, families and genus groups according to otolith morphologies 27 27 27 28 28 29 5.4 Discussion of phylogenetic concepts in Pleuronectiformes ............................................................. 36 6. Morphological characterization of Pleuronectiformes otoliths .................................................................. 6.1 Terminology .............................................................................................................................................. 6.2 Side dimorphism ..................................................................................................................................... 6.3 Variability and ontogenetic trends ........................................................................................................ 6.4 Otoliths of reversed individuals ........................................................................................................... 6.5 Sexual dimorphism ................................................................................................................................. 41 41 45 51 53 55 7. Descriptive part .................................................................................................................................................. 7.1 Psettodidae: Psettodes .............................................................................................................................. 7.2 Genera of uncertain relationship .......................................................................................................... 7.2.1 Tephrinectes Group: Tephrinectes ................................................................................................ 7.2.2 Paralichthodes Group: Paralichthodes ......................................................................................... 7.2.3 Ammotretis Group: Collistium, Ammotretis, Oncopterus, [Psammodiscus], [Taratretis] ........ 57 57 62 62 63 65 7.3 7.4 7.5 Citharidae: Citharus, Paracitharus, Citharoides, †Rhombocitharus ....................................................... Brachypleuridae: Lepidoblepharon, Brachypleura .................................................................................. Scophthalmidae ........................................................................................................................................ 7.5.1 Scophthalmus Group: Scophthalmus .......................................................................................... 7.5.2 Lepidorhombus Group: Lepidorhombus ...................................................................................... 7.5.3 Zeugopterus Group: Zeugopterus, Phrynorhombus ................................................................... 70 84 89 90 92 100 7.6 Bothidae .................................................................................................................................................... Paralichthyinae 7.6.1 Paralichthys Group: Ancylopsetta, Gastropsetta, Hippoglossina, Xystreurys, Lioglossina, Paralichthys ................................................................................................................................... 7.6.2 Pseudorhombus Group: Pseudorhombus, Tarphops, [Cephalopsetta] ........................................ 7.6.3 Syacium Group: Syacium, Cyclopsetta ....................................................................................... 7.6.4 Citharichthys Group: Citharichthys, Orthopsetta, Etropus ....................................................... 104 Bothinae 7.6.5 Bothus Group: Bothus, Parabothus, Grammatobothus .............................................................. 7.6.6 Arnoglossus Group: Neolaeops, Arnoglossus, Caulopsetta, Lophonectes, Psettina, Taeniopsetta ............................................................................................................................................. Footnote: Genera listed in brackets are not represented by otoliths. Piscium Catalogus, Part Otolithi piscium, Vol. 2 106 124 135 145 157 165 6 7.6.7 Monolene-Laeops Group: Trichopsetta, Engyophrys, [Perissias], Laeops, [Japanolaeops], Monolene ....................................................................................................................................... 7.6.8 Engyprosopon Group: Asterorhombus, Engyprosopon, Crossorhombus, [Tosarhombus] ......... 7.6.9 Thysanopsetta Group: Thysanopsetta ......................................................................................... 7.6.10 Chascanopsetta Group: Chascanopsetta, [Pelecanichthys], [Kamoharaia] ................................. 7.6.11 Mancopsetta Group: Mancopsetta, [Achiropsetta] ..................................................................... 7.7 7.8 7.9 8. Pleuronectidae .......................................................................................................................................... Pleuronectinae 7.7.1 Hippoglossus Group: Eopsetta, Hippoglossus ............................................................................ 7.7.2 Hippoglossoides Group: Atherestes, Cleisthenes, Lyopsetta, Acanthopsetta, Hippoglossoides, Reinhardtius .................................................................................................................................. 7.7.3 Glyptocephalus Group: Glyptocephalus, Tanakius ..................................................................... 7.7.4 Pleuronectes-Limanda Group: Limanda, Dexistes, Liopsetta, Parophrys, Pleuronectes, Platichthys, Kareius, Pseudopleuronectes, Lepidopsetta, Inopsetta ................................................................. 7.7.5 Isopsetta Group: Psettichthys, Isopsetta ..................................................................................... 7.7.6 Verasper Group: Verasper, Clidoderma ....................................................................................... 7.7.7 Microstomus-Pleuronichthys Group: Microstomus, [Embassichthys], Pleuronichthys, Hypsopsetta ............................................................................................................................................. 189 199 205 206 208 210 212 214 223 226 241 243 245 Rhombosoleinae 7.7.8 Pelotretis Group: Pelotretis ......................................................................................................... 7.7.9 Rhombosolea Group: Rhombosolea .............................................................................................. 250 252 Samarinae 7.7.10 Samaris Group: Plagiopsetta, Samaris, Samariscus, Azygopus ................................................ 254 Poecilopsettinae 7.7.11 Marleyella Group: Marleyella ..................................................................................................... 7.7.12 Poecilopsetta Group: Poecilopsetta, Nematops ............................................................................ 264 265 Soleidae ..................................................................................................................................................... Achirinae 7.8.1 Achirus Group: Trinectes, Achirus, Catathyridium, Hypoclinemus, Gymnachirus, Nodogymnus .......................................................................................................................................... 7.8.2 Apionichthys Group: Apionichthys, [Achiropsis], [Pnictes], [Soleonasus] ............................... 269 270 279 Soleinae 7.8.3 Solea Group: Microchirus, Monochirus, Quenselia, Dicologlossa, Solea, [Dageichthys], Microbuglossus, Vanstraelenia, Bathysolea ............................................................................................... 7.8.4 Synaptura Group: Austroglossus, Synaptura ............................................................................ 7.8.5 Brachirus Group: Heterobuglossus, Dexillichthys, Brachirus, Anisochirus, Phyllichthys ....... 7.8.6 Zebrias Group: Aesopia, †Granultihus, Soleichthys, Pseudaesopia, Zebrias, [Typhlachirus] ... 280 306 310 316 Pardachirinae 7.8.7 Pardachirus Group: †Praeachirolithus, Aseraggodes, †Pseudopardachirolithus, Pardachirus, [Parachirus] ................................................................................................................................... 7.8.8. Heteromycteris Group: Heteromycteris, Rendahlia, Peltorhamphus ......................................... 323 330 Cynoglossidae .......................................................................................................................................... 7.9.1 Cynoglossus Group: Cynoglossus ............................................................................................... 7.9.2 Symphurus Group: Symphurus .................................................................................................. 338 339 359 Selected Literature .............................................................................................................................................. 368 Index 373 Footnote: ....................................................................................................................................................... Genera listed in brackets are not represented by otoliths. Schwarzhans: Pleuronectiformes 7 1. Introduction and Acknowledgements The fishes of the order Pleuronectiformes, or flatfishes as they are commonly known, are readily recognized by their high degree of external asymmetry. This asymmetry has developed as a response to their benthic life-style. Unlike other flat bodied bottom-living fishes, which have become laterally expanded and vertically compressed, such as rays or certain monkfishes, Pleuronectiformes are derived from some kind of presumably deep bodied vertically oriented fish, which sort of “laid down sideways on the ground”. As a result of this habit adult Pleuronectiformes developed a set of unique asymmetrical features both externally and internally, involving the soft organs as well as the skeleton and, of course, the otoliths (larvae are bilaterally symmetrical). For instance the eye on the side facing ground moves over the top of the head to a position close to the eye on the other side. This results in a “blind” side and an “eyed” side. The skull, mouth, and the anterior vertebrae, all look “distorted”. The fins, lateral line system, coloration, even the dentition of the mouth and many other characters are often distinctly asymmetrical. In combination the resulting asymmetry is so eye-catching and so different from any other fish that the Pleuronectiformes (or Heterosomata, which better refers to their appearance) have almost always been understood as a well defined “natural” systematic unit. The asymmetrical specialization of Pleuronectiformes appears to have been a very successful adaption. Nowadays, flatfishes occur in practically every ocean and are represented by a large number of species (more than 550) and genera (about 132, plus 4 fossil otolith based genera) distributed amongst 6 to 11 families or more depending on the view of individual taxonomists. Many flatfishes are of considerable commercial importance. Such names as turbot (Steinbutt; Scophthalmus maximus), plaice (plie, Scholle; Pleuronectes platessa) or sole (Seezunge; Solea solea) are well known from European fish markets and so are their equivalents from fish markets throughout the world. Through the systematic works of NORMAN (1934), CHABANAUD (div.) and many other authors our status of knowledge of pleuronectiform fishes is very good. However, amongst teleost groups of comparable size, the otoliths of the order PleuronectiPiscium Catalogus, Part Otolithi piscium, Vol. 2 formes are amongst the least well known. The work by CHAINE (1936), notable for its superb photographic technique, stands alone. Unfortunately, some of the illustrations are too small to be of practical use. The reasons for this discrepancy are, I believe, twofold. Firstly, ichthyologists working with recent material appear to have been content with the amount of information gathered from the complete fish and have paid little care to what the analysis of otoliths might reveal. Secondly, paleoichthyologists, who in the past have been the driving force for investigations of otolith morphology, in both fossil and living fishes, have been more interested in other Teleost groups which seemed to promise higher rewards. Indeed, pleuronectiform otoliths are not the easiest to work with morphologically. Taxonomic work is somewhat hampered by the often high degree of intraspecific variability, the low level of interspecific morphological differentiation and of course the ubiquitous effects of asymmetry. However, morphological differentiation is possible in most cases and in some it may contribute to a better understanding of pleuronectiform systematics, as I hope this monograph is able to demonstrate. My ambition to prepare a comparative morphological study of pleuronectiform otoliths and to make it as comprehensive as possible was triggered by the very extensive collection of recent flatfishes in the collection of The Natural History Museum, formerly British Museums (Nat. Hist.), in London. The major portion of the flatfish collection was put together by J. R. NORMAN when he prepared his “Systematic monograph of the flatfishes (Heterosomata) – Vol. 1: Psettodidae, Bothidae, Pleuronectidae” (1934). (The second part that was proposed to cover the Soleidae and Cynoglossidae was unfortunately never completed due to the early death of NORMAN.) This collection offered a unique opportunity to accumulate a large amount of pleuronectiform otolith data from a single location and in short time, and also had the advantage that the fishes had been identified by one of the most distinguished flatfish taxonomists. In this treatise I tried to compile and figure as much data as possible for both recent and fossil pleuronectiform otoliths. Recent otoliths figured represent 116 genera of the 132 currently recog- 8 nized and more than 300 species corresponding to more than 50 % of the known recent species. Largest gaps of otolith knowledge are within the specious genera Bothus, Laeops and Engyprosopon (Bothidae), Samariscus (Pleuronectidae), Trinectes, Achirus, Brachirus and Aseraggodes (Soleidae) and Symphurus (Cynoglossidae). I have concentrated my efforts on the Pleuronectoidei and therefore otoliths of the Soleidae and Cynoglossidae are somewhat less well represented (particularly the freshwater soleids of America). However, many of the missing genera (and species, too) are very rare fishes which are kept in various collections at different locations. I felt that extending the study to these taxa would entail very much time and effort but provide relatively little additional information. The extent of the data collected for this study represents a considerable advance on previously published information and was considered sufficiently comprehensive to prepare the following treatise. As with the previous (and first) volume in the newly established Otolithi Piscium Catalogus format – “A comparative morphological treatise of recent and fossil otoliths of the family Sciaenidae” (SCHWARZHANS 1993) – I have put great emphasis on large and, I hope, clear and detailed drawings. Whenever possible, I tried to figure more than just one specimen of each species to document intraspecific variability, morphological asymmetry when and where it occurs and ontogenetic changes in morphology. The compilation of all these recent data would have been impossible without the most generous help and support which I received from the following co-scientists and institutions. First and foremost I wish to cordially thank the authorities of The Natural History Museum (BMNH, London) and in particular Mrs. N. Merrett and O. Crimmen. Another major source of recent material have been otoliths donated by the late J. Fitch, mostly from the Pacific coast of North and Middle America. Further I wish to cordially thank: Mrs. Dose, Mrs. C. Karrer, A. Post and H. Wilkens (Zoologisches Museum Hamburg – ZMH; and Institut für Seefischerei, Hamburg – ISH now transferred to ZMH), J. Nielsen (Universitetets Zoologiske Museum, Kobenhavn – ZMUC), D. Nolf (Institut Royale des Sciences Naturelles de Belgique, Bruxelles – IRSNB), F. Krupp (Senckenberg Museum, Frankfurt/M. – SMF), W. Schmidt (Vockenhausen, Germany), K. Sasaki (Kochi University, Kochi), F. Ohe (Nagakute Senior High School, Aichi), H. Grenfell (University of Auckland), G. Allen (West Australian Museum, Perth – WAM), R. Mckay (Queensland Museum, Brisbane – QMB), P. Castle (National Museum of New Zealand, Wellington – NMNZ), T. Hecht (Rhodes University, Grahamstown) and J. Paxton (Australian Museum, Sydney – AMS). The majority of the described fossil pleuronectiform otolith species are revised. As far as possible these revisions are based on a review of the type-material or newly collected material preferably from the type-localities. Wherever appropriate, type specimens are being refigured. All these valuable data were made available most generously by: F. Stojaspal (Geologische Bundesanstalt, Wien – GBW), D. Nolf (Institute Royale des Sciences Naturelles de Belgique, Bruxelles – IRSNB), H. Malz (Senckenberg Museum, Frankfurt/M. – SMF P), E. Martini (Universität Frankfurt), W.-D. Heinrich (Paläontologisches Museum der Humboldt-Universität zu Berlin – PMHUB), R. Niederl (Steiermärkisches Landesmuseum Joanneum, Graz – LMJ), Mrs. A. Mastandrea (Universita di Modena – IPUM), C.H. v.Daniels (Niedersächsisches Landesamt, Hannover – NLH) and from the private collections of F. Pfeil (München), Mrs.U. Radwanska (Warszaw – IGUW), E. Richardson (Henderson, New Zealand), J. Boscheinen (Düsseldorf), C. Klinger (Düsseldorf), F. von der Hocht (Kerpen), W. Wienrich (Weetze, Niederrhein), M. Möller (Kleve) and W. Neumann (Krefeld). The material kindly made available through these co-scientists and institutions allowed for the first time an almost complete revision of the largest fossil pleuronectiform fauna known to date: that from Central and Western Europe. Other important fossil flatfish faunas reviewed include those described from Central America and New Zealand. Unfortunately, fossil pleuronectiform otoliths described from Kazakhstan, Japan and Indonesia have not been available for revision. Fossil pleuronectiform otoliths are fairly well known from Central and Western Europe and from New Zealand, but from other regions in the world our knowledge is still very limited. In future years I would expect many new fossil flatfish otoliths to surface from such areas and I hope that this monograph will contribute to a better understanding of them. The rich recent flatfish faunas in Central America, Japan or Indonesia already indicate the vast potential range of fossil forms to be expected from such areas. However, Schwarzhans: Pleuronectiformes 9 from newly collected material by F. Pfeil, W. Wienrich and myself some new fossil species are being described. They have been obtained from locations in Northern Germany, Austria, New Zealand and Morocco, the latter representing the first fossil pleuronectiform otoliths from Africa. I wish to thank Mr. O. Crimmen (London) for reviewing major parts of the manuscript for English language. 2. Catalogue of Investigated material Recent and fossil pleuronectiform otoliths have been investigated from the following institutional collections: AIM AMS AUG Auckland Institute and Museum Australian Museum, Sydney Auckland University, Geology Department BMNH Natural History Museum), London BSP Bayer. Staatssammlung für Paläontologie und hist. Geologie, München GBW Geologische Bundesanstalt, Wien GPIM-M Paläontologische Institut der Universität Mainz IPUM Instituto di Paleontolgia, Universita di Modena IRSNB Institut Royale des Sciences Naturelles de Belgique, Bruxelles ISH Institut für Seefischerei, Hamburg (now ZMH) LMJ Steiermärkisches Landesmuseum Joanneum, Graz NLH Niedersächsisches Landesamt, Hannover NMB Naturhistorisches Museum, Basel NMNZ National Museum of New Zealand, Wellington NZGS New Zealand Geological Survey, Lower Hutt PMHUB Paläontologisches Museum der Humboldt-Universität, Berlin QMB Queensland Museum, Brisbane SIO Scripps Institution of Oceanography, La Jolla SMF Senckenberg Museum, Frankfurt/M. USNM National Museum of Natural History, Washington D.C. WAM West Australian Museum, Perth ZMH Zoologisches Museum der Universität Hamburg ZMUC Universitetets Zoologiske Museum, Kobenhavn Piscium Catalogus, Part Otolithi piscium, Vol. 2 ZPalUW Institute of Geology of the University of Warsaw and the following private collections: J. Boscheinen – Düsseldorf (type-material at SMF) J. Fitch (material donated to the author – Fitch’s main collection is now at LACM) H. Grenfell – Auckland (material at AIM and AUG) T. Hecht – Grahamstown (material donated and loaned to the author) F. von der Hocht – Kerpen (type-material now at GPIM-M) C. Klinger – Düsseldorf (type-material at SMF) E. Martini – Frankfurt/M. (material at University of Frankfurt) P. Maxwell – Waimate (type-material now at NZGS) M. Möller – Kleve (type-material now at SMF) W. Neumann – Krefeld (type-material at SMF) D. Nolf – Brugge (material now at IRSNB) F. Ohe – Aichi (private collection kept at Nagakute Senior High School) F. Pfeil – München (material now catalogued at BSP) U. Radwanska – Warszaw (material now at ZPalUW) E. Richardson – Henderson (type-material now at NZGS) K. Sasaki – Kochi (material donated to the author) W. Schmidt – Vockenhausen near Stuttgart (material donated to the author) W. Schwarzhans – Mülheim a.d. Ruhr (recent material now catalogued at ISH/ZMH; fossil type-material now at NZGS, SMF and GBW) E. Steurbaut – Bruxelles (material now at IRSNB) W. Wienrich – Weetze (type-material now at SMF) Recent otoliths are usually stored separately from the fishes from which they were obtained. It is 10 therefore important to give a track record of each recent otolith specimen as complete as possible. Unfortunately, this data is not always available. In recent times the necessity providing good specimen data has become more and more apparent to otolith workers. (My own collection techniques have changed in this respect.) In most institutional collections dissected otoliths are kept under the same catalogue number as the fish. In fossil collections of course catalogue numbers refer only to the otoliths. In addition, in private collections and also in some institutional collections, there exists a large amount of non-catalogued material. In citations of material examined for this treatise the collection number (followed by the catalogue number when available) is always noted first and without brackets or quotation marks. Additional information may follow in brackets, for instance: Collection and catalogue number of the fish from which the otolith was dissected when not identical with present location of the otolith specimen. Prefix – leg. – for material that was donated from private or institutional collections. Prefix – coll. – for material that is or was originally kept in a private collection and became subsequently submitted to an institutional collection. Any type-material investigated or lectotypes or neotypes newly selected are quoted accordingly. The recent otoliths of my formerly private collection are being transmitted to the ISH collection (now transferred to the ZMH collection), with the provision of a lifetime loan-agreement for myself. This material is not yet catalogued, but will be catalogued in the course of it being published. This will greatly increase the accessibility of the collection. These otoliths will be catalogued in a new ZMH (formerly ISH) catalogue format obeying the following the rules: ZMH Ot. (stands for assigned otolith collection) day.month.year.current number (corresponds to the time when the otolith was actually catalogued). This system is similar to that at the BMNH. 3. Distribution of recent Pleuronectiformes Flatfishes are adapted to a benthic life-style. They spend most of their time on the bottom resting on the blind side. Often they bury themselves in the sediment, with only the eyes and nostrils uncovered. Some flatfishes, however, are regularly caught pelagically (Hippoglossus, Reinhardtius). Psettodes and Reinhardtius are known to adopt a vertical posture, at least occasionally, the latter genus probably does so as a secondary adaption to its pelagic way of living. Flatfishes are widely distributed in the shallow seas of the world. They are most common in near-shore environments and down to the continental break (10 to 200 m). Some genera and species, however, live at greater depths on the continental rise (for example Lepidorhombus boscii, Arnoglossus rueppelli, Chascanopsetta, Mancopsetta, Hippoglossus, Glyptocephalus, Poecilopsetta, Bathysolea or Symphurus). Some flatfishes are also found close inshore, in tidal and subtidal environments and even in estuarine and brackish waters. Truly freshwater Pleuronectiformes are rare, most of them representatives of the family Soleidae (Achi- rus and Apionichthys Groups). Their occurrence is restricted to tropical rivers and estuaries, particularly in South America, but also in Africa, the Indo-Malayan archipelago and northern Australia. Due to their benthic habit flatfishes are often adapted to certain kinds of substratum. They are most abundant in clastic environments on soft muddy or sandy bottoms. Some genera and species are specialized on hard pebbly or rocky bottoms (for example Phrynorhombus, Zeugopterus). But apparently there are also some genera which occur regularly in coral reef environments (for example Samariscus) or lagoonal facies settings. Flatfishes are carnivorous, feeding mostly on other fish, squids and crustaceans. The largest flatfishes, like the giant Hippoglossus which can reach 2 m in length or Reinhardtius are active predators feeding on a variety of prey, but mostly fish, squids and prawns. Most other flatfishes hide on or partially submerged in the sediment waiting for prey to pass within reach. Soleidae and Cynoglossidae are adapted to feed on bottom living invertebrates (worms, bivalves etc.). Soleidae are Schwarzhans: Pleuronectiformes 11 mostly nocturnally active “creeping” over the sediment in the search of their prey. The Cynoglossidae are adapted primarily to ploughing the sand in search of prey and to feeding on organisms living below the surface. Geographically, Pleuronectiformes are distributed throughout the world oceans from the Subarctic in the north (about 75°N) to the Subantarctic in the south (about 55°S, just north of the Antarctic front), with one species (Mancopsetta maculata) having been collected off the coast of Antarctica. They are most common and specious, however, in tropical and subtropical seas. NORMAN (1934) produced a diagram (p.49) depicting the latitudinal range of pleuronectiform families and subfamilies. From this it can be seen that the majority of flatfishes are distributed between the Tropic of Cancer and the Tropic of Capricorn (Psettodidae, many Bothidae, Cynoglossidae, most Soleidae and the pleuronectid subfamilies Poecilopsettinae and Samarinae). However, there are also certain families and groups with a distinctly antitropical distribution pattern. The Citharidae are known from the temperate to subtropic seas of Europe and West Africa (Citharus), South Africa (Paracitharus) and Japan (Citharoides). Scophthalmidae as a family are exclusively known from the North Atlantic (most species from the Northeast Atlantic, only one from the Atlantic coast of North America) and between the Arctic Circle and the Tropic of Cancer. Likewise the majority of the Pleuronectidae (subfamily Pleuronectinae in NORMAN 1934) is restricted to the temperate and subtropic waters of the North Pacific and the North Atlantic. The Rhombosoleinae (Pelotretis, Rhombosolea and Ammotretis Groups as defined here) are endemic to the Southern Oceans, chiefly around New Zealand, southern Australia and with one species off Patagonia (South America). It has been argued that the geographical spread of shallow marine benthic fishes would to a certain extend depend on the pelagic larval phase (see discussion in NORMAN 1934; p.30-33). This would be particularly important for flatfishes, which are not very active swimmers and are mostly rather sedentary during their adult life, (exceptions are the more active swimmers like Hippoglossus, Reinhardtius or Glyptocephalus, and indeed these are much more widely distributed). The eggs of the great majority of the Pleuronectiformes are buoyant and pelagic as are their larval stages. Accepting the pelagic life of eggs and Piscium Catalogus, Part Otolithi piscium, Vol. 2 larvae as the principal phase during which geographical spreading of flatfishes may occur, it becomes obvious that two factors largely control their distribution patterns – 1. nature and orientation of oceanic surface currents both in the Recent and the geological history, and 2. the length of the pelagic larval life. As for the latter NORMAN (1934) noted that in most Pleuronectinae the pelagic life is very short, whereas that of the genera Arnoglossus and Bothus is considerably prolonged. He also assumed a prolonged early pelagic life for the genera Syacium and Citharichthys, both in essence new world genera known from a single species each from the West African coast. A similar situation is recorded for the Miocene, from which a true Syacium species (S. syacioides, not related to the recent S. micrurum from the West African coast) has been described from Austria. In general, however, the spreading of pleuronectiform genera or even species across major deep ocean “barriers” remains the exception rather than the rule. Indeed one notes a relatively distinct regionalisation in the distribution pattern of the Pleuronectiformes. Many flatfish genera seem to be endemic to certain regions and likely have been so during their evolution. I assume that most endemic genera of this type represent true primary endemics. In the Pleuronectoidei the largest number of endemic genera is known from the seas around Japan, Northern China and Korea (11 genera), the Pacific coast of America (particularly California; 10 genera) and the temperate seas around New Zealand and southern Australia (8 genera). 4 genera are endemic to Europe and Northwest Africa (Citharus, Lepidorhombus, Phrynorhombus and Zeugopterus), 3 genera each to the seas of Indonesia and Southeast America, 2 genera each to the Subantarctic and to South Africa and 1 genus each to Southwest America, Hawaii and tropical eastern America. The 4 genera endemic to Europe and Northwest Africa seem to have long reaching and well established fossil records in the same area since at least Oligocene times. However, one of the genera thought to be endemic for South Africa probably also had a fossil record from Europe (Paracitharus angustus from the Pliocene), indicating that its present restriction to South Africa probably represents a secondary endemism. (Similar observations have been made for other present day endemic fishes of South Africa as well – for instance Afroscion of the family Sciaenidae (SCHWARZHANS 1993) 12 and Bidenichthys of the family Bythitidae (SCHWARZHANS 1994). The geographically isolated subtropic and temperate seas around South Africa seem to represent an ideal refugium for “living fossils” in the marine life.) In the Soleoidei regionalization seems to be developed best in the Soleidae. For instance the Achirus and Apionichthys Groups are restricted to the Americas, whereas all other groups are strictly old world representatives with the highest degree of diversity in the Indopacific (Brachirus, Zebrias, Pardachirus and Heteromycteris Groups). Biogeographic analysis of the soleid genera is somewhat hampered by the often unclear delimitation of generic definitions. Therefore, 7 genera are tentatively accepted as endemic to the central Indopacific (Philippines, Indonesia and northern Australia, of which 1 is endemic to Indonesia and 3 to Australia), 6 genera are endemic to South America (several of them freshwater genera), and 4 are endemic to Europe and North Africa. Endemism in other bioprovinces is less well developed: 2 genera in West Africa, 1 in South Africa, 1 in Japan (not counting the problematical Rhinosolea) and 1 genus in New Zealand (assuming Peltorhamphus to represent a soleid). As can be seen from the above listing the majority of pleuronectoid endemics occur in temperate to subtropic waters, whereas the majority of soleoid endemics are tropical (several of them in freshwater). However, they rarely exceed 10 to 20 % of the total pleuronectiform fauna. This is even true for those bioprovinces with a very high number of endemic genera, such as Japan or California. The only notable exception is the flatfish-fauna from New Zealand and southern temperate Australia. There, 8 out of 15 genera are endemic. Of these endemics 5 are only known from New Zealand. This high degree of presumably primary endemics is evidently caused by the isolation of the two regions effective for a considerable interval of time in geological history. Paleontological findings (see chapter 4.3.5) support this concept. 4. Fossil Pleuronectiformes otoliths 4.1 Systematics of fossil Pleuronectiformes otoliths Pleuronectiform otoliths are not uncommon in the fossil record, although they rarely occur in very great numbers. Since flatfishes are mainly adapted to shallow marine soft bottom environments it is not surprising that they are also specious and common in adequate sediments. But they are also known, both recent and fossil, from the deeper shelf or the continental rise. Some genera are adapted to rocky or reef environments. These are represented extremely rarely in the fossil record due to the poor fossilization potential of the aragonitic otoliths in carbonatic rocks which prevail in such settings. So far no fossil pleuronectiform otoliths are known from true freshwater sediments. In the stratigraphic record pleuronectiform otoliths are known best from the Oligocene onward. The oldest certain records date back into Early Eocene times and are generally represented by rather plesiomorphic groups such as the genera Psettodes and Rhombocitharus. But it also comprises a surprisingly “modern” looking both- id of the genus Arnoglossus. In the Upper Eocene two Soleidae are added to the list representing extinct genera (Praearchirolithus and Pseudopardachirolithus) of the Pardachirinae. In the Upper Eocene and Lower Oligocene the number of “modern” pleuronectiform otoliths increases (a second Arnoglossus species from New Zealand, two soleid species and Brachypleura). Records from the Oligocene and the Neogene reflect a wide spectrum of families. So far the most commonly recorded families have been the Bothidae (particularly the Arnoglossus Group), Soleidae (Solea Group) and the Citharidae. The Cynoglossidae, Scophthalmidae and even the Brachypleuridae are known as well, but less commonly. Amazingly, the poorest fossil knowledge refers to the Pleuronectidae. From this family only two fossil species have been noted for certain, one from the Upper Oligocene of northern Germany (SCHWARZHANS 1994), the other from the Lower Pliocene of New Zealand described as new below. However, some extant species have been recorded from the Upper Pliocene and Pleistocene of California (FITCH, div. pub.) and Japan (OHE 1981, 1983). Schwarzhans: Pleuronectiformes 13 To date (and including this monograph) about 124 fossil pleuronectiform species based on otoliths have been described, mostly from Europe and New Zealand. In addition about 47 recent species have also been described as fossils from Pliocene to Pleistocene sediments of Europe, North America and Japan. About half of the fossil species are here accepted as valid, i.e. 60 fossil species (including 18 described as new) and 35 of the recent species recorded as fossils. Of the three previously established fossil otolith based genera – Citharopsettodes, Eosolea and Rhombocitharus – only Rhombocitharus is here regarded as valid; Citharopsettodes is placed in synonymy with Paracitharus and Eosolea is not a pleuronectiform. In addition, three new fossil otolith based genera are described – Granulithus, Praearchirolithus and Pseudopardachirolithus. [The formal ending “lithus” has been attached to the names to indicate that they are otolith-based fossil genera.] From the inception of otolith research, fossil pleuronectiform otoliths have been described by KOKEN, SCHUBERT, BASSOLI and others. Most of their species are still regarded as valid. However, their figures and descriptions have often been inadequate to allow recognition of the delicate features that distinguish closely related species from each other. Good documentation and diagnosis is particularly important in this group due to the high degree of intraspecific variability, the often relatively low level of interspecific morphological differentiation and the prevalence of poorly preserved or juvenile otoliths lacking diagnostic features in the fossil record. As a result of this problematic situation secondary references in subsequent publications suffer from inadequate identifications. In fact the taxonomic situation can only be described as chaotic in many instances. Sorting out all the secondary references that have occurred will be a very laborious task. And before such a task can be realized the type-material of the earlier works needs to be thoroughly revised. Such a revision, the re-figuring of types wherever appropriate and the description of a detailed differential diagnosis is one of the major objectives of my study (see next chapter) and hopefully it will help towards a better identification of fossil pleuronectiform otoliths in future investigations. The results of other important revisions recently made by NOLF (1981; SCHUBERT’s type-material), STEURBAUT & JONET (1981; JONET’s type-material), NOLF & STEURBAUT (1983; BASSOLI’s type-material) Piscium Catalogus, Part Otolithi piscium, Vol. 2 and SCHWARZHANS (1994; KOKEN’s typematerial) have been incorporated. In addition other type-material or new material from typelocations was reviewed insofar as it was available. However, I regret that there remains still a number of important type specimens that could not be investigated. This is particularly true for the otoliths described by POBEDINA (1954) and SUZIN (1968) from the Miocene of Kazakhstan, which are mostly based on juvenile otoliths for the greater part and are therefore presently regarded as of doubtful identity. This also applies to the otoliths described by FROST (1925), VORSTMANN (1927) and HATAI (1965) from the Tertiary of Indonesia and Japan. Secondary references have only been taken into consideration when the specimens have been reviewed or they are sufficiently identifiable from the illustrations of the respective publications. In early publications the diagnostic features of pleuronectiform otoliths, namely the circumsulcal depression (see chapters 5.1. and 6.1. for explanation), were not recognized. Therefore, a number of otoliths have originally been described as representing pleuronectiforms of some sort which must in fact now be regarded as belonging to other Teleosts. This is the case for at least 26 nominal species, an unusually high percentage. In one case, even a genus – Eosolea DANTE & FRIZZELL 1965 – based on otoliths, and thought to be a Soleidae, is not in fact a pleuronectiform. All the species referred to this nominally valid genus have been identified as belonging to the Anguilliform family Heterenchelyidae (NOLF & MARTINELL 1980). On the other hand, only 2 species have been transferred from a systematic position outside the Pleuronectiformes into this order. As already pointed out the number of doubtful fossil species needing thorough revision is still as high as 20. I strongly recommend against the use of these species names although they are nominally valid until proper revisions have been carried out. 15 fossil species are regarded as synonyms, 2 are rejected as having been based on indeterminable material and 1 represents a nomen nudum. In more recent literature from the 70s onward the taxonomic problems prevailing in earlier publications and the difficulties involved in distinguishing otoliths of related flatfish species became widely recognized by otolith research workers and led to a drastic change in their atti- 14 tude when describing fossil pleuronectiform otoliths. Quite often we now find pleuronectiform otoliths placed in open nomenclature (NOLF, RADWANSKA, SCHWARZHANS, STEURBAUT). Fortunately, this attitude has stopped the introduction of an ever increasing amount of illdefined new fossil taxa. Now that the majority of the type-material is being revised and a previously unpreceded amount of recent data is available, new species may be better defined. However, it is strongly recommended that in the establishment of new fossil species certain rules are observed which should be common sense anyway: – Making sure that the type-material is of good quality, is sufficient to demonstrate that the diagnostic characters do not fall within the variability range of a previously described species and represents truly adult specimens that exhibit enough characters of diagnostic value. Also it is my suggestion to make significant efforts to provide illustrations that are as detailed as possible in order to facilitate future references. This last point I wish to stress in particular since in the past many illustrations have been published that are inadequate for accurate interpretation. Unfortunate examples are the publications of FROST, STINTON and some early works of NOLF. If such type-material is ever mislaid (and in the case of FROST some of it evidently has been) it will be almost impossible, without extensive re-collecting at the type-location (and sometimes not even then), to “reconstruct” the nature of the respective species. Another attitude adopted in more recent studies and obviously born of the same insight is that of placing fossil flatfish otoliths, particularly those from the Younger Tertiary, in living species often accompanied with some prefix like aff. or cf. This method is somewhat more problematical. It intends to reflect a status of knowledge which in fact is not quite the case. Several of these recent species described as fossils are based on single and/or poorly preserved specimens that should better be left in open nomenclature (see chapter 4.2). A clear example of such a misguided attempt at positive identification is even found in the publication of such a competent otolith specialist as OHE (1983), who described several recent European pleuronectiform species from the Pliocene of Japan, such as Arnoglossus cf. laterna, Solea cf. solea or Solea cf. lascaris. Judging from his photographs most of these are either undeterminable, eroded and/or juvenile specimens or rep- resent extant Japanese species. In this light I wish to recommend following the rules outlined above (for the erection of new fossil taxa) for the allocation of any fossil otolith to a recent species. In fact, when reading more recent literature on fossil otoliths one definitely gets the impression that fossil pleuronectiform otoliths have not been a favored group to anybody. For instance NOLF (1985) noted that the intraspecific variability in flatfish otoliths is unusually wide, but: “if one has a good series of otoliths, the characters of the species can still be recognized”. SCHWARZHANS (1984) wrote in an introductory chapter to the Soleoidei that “the morphology is strongly reduced” and that “here may be one of the few cases (in Teleosts), where otoliths of related species are not always distinguishable”. There is a lot of truth in both statements. Pleuronectiforms are indeed among the few Teleost groups where we have to accept that not all related species may be distinguishable on the basis of otoliths alone. Particularly when dealing with fossils one should treat certain “species” with very generalized morphologies more like “species groups” than fully defined species (see entries on Microchirus frequens and Microchirus kirchbergeanus for instance). However, it is also true that with a large series of specimens diagnostically valid characters can still be defined to distinguish such related species. This observation not only calls for a “conservative” approach in taxonomic analyses, but also means that isolated specimens, particularly when eroded or juvenile, cannot always be attributed to a certain species. 4.2 Revision of fossil Pleuronectiformes otoliths The following is an alphabetical list of fossil pleuronectiform species which are based on otoliths. Each species name is followed by author and original designation in brackets and the revised designation as adopted here. This list includes every otolith based species originally described as a pleuronectiform and species that have been described as belonging to some other Teleost order but are now accepted as pleuronectiforms. Wherever revisions of other authors are adopted this is noted. Species accepted as valid are shown in bold print. Schwarzhans: Pleuronectiformes 15 At the beginning of every new line symbols show what material has been available for reexamination. An asterisk (*) denotes re-examined holotypes or selected lectotypes, # denotes paratype(s) or syntype(s) (but no holotype) or any other specimen collected from the type-locality, a small “s” denotes any other specimens. In separate lists, doubtful species (based on inconclusive type material or still needing revision) and also recent species that have been described as fossils are put together. Finally, valid fossil species and recent species recorded as fossils are listed in their current systematic position. * * s s * s * * s s * s acuminatus KOKEN 1891 (Pleuronectidarum) – Bythitidae alta STEURBAUT & JONET 1981 (Paraplagusia) – syn. Cynoglossus leuchsi altus POBEDINA 1954 (Rhombus) – doubtful species, probably a true pleuronectiform, possibly a Pleuronectidae, but cannot be evaluated from figures altus MENZEL 1986 (Cynoglossus) – syn. Cynoglossus leuchsi angulata FROST 1925 (Solea) – doubtful species, drawing very schematic angulosus NOLF 1976 (Lepidorhombus) – Lepidorhombus angulosus angulosus NOLF 1976 (sensu RADWANSKA 1992) – syn. Lepidorhombus subtriangularis angustus SCHWARZHANS 1978 (Citharopsettodes) – Paracitharus angustus aomoriensis HATAI 1965 (Limanda) – doubtful species approximata KOKEN 1891 (Solea) – type lost, can not be evaluated from the illustrations, species rejected (see entry on Microchirus frequens) arnoglossoides n.sp. – Caulopsetta arnoglossoides awamoaensis n.sp. – Grammatobothus awamoaensis balangoensis VORSTMANN 1927 (Solea) – doubtful species balearicus BAUZA RULLAN 1955 (Eucitharus) – syn. Citharus balearicus bartonensis FROST 1934 (Solea) – Heterenchelyidae bassolii SCHUBERT 1906 (Phrynorhombus) – sulcus of unique type eroded, doubtful species, not a pleuronectiform bauzai SANZ ECHEVERRIA 1950 (Arnoglossus) – syn. Arnoglossus kokeni Piscium Catalogus, Part Otolithi piscium, Vol. 2 * s * s * * s * * * * * * * bavayi NOLF 1988 (Psettodes) – genus aff. Psettodes bavayi belgicus GAEMERS 1972 (Eucitharus) – syn. Rhombocitharus rhenanus biaculeatus NOLF & LAPIERRE 1979 (Bothidarum) – Rhombocitharus biaculeatus boerialensis VORSTMANN 1927 (Pleuronectes) – Congridae cauneillensis NOLF 1988 (Citharus) – Rhombocitharus cauneillensis circularis STINTON 1966 (Eucitharus) – Rhombocitharus circularis claibornensis DANTE & FRIZZELL 1965 (Eosolea) – Heterenchelyidae collatus NOLF 1972 (Psettodes) – Psettodes collatus concaviventris n.sp. – Etropus concaviventris concavus PRIEM 1914 (Pleuronectidarum) – Pomadasyidae contortus FROST 1934 (Bothus) – doubtful species (see NOLF 1985) corius CHALIKOV 1946 (Rhombus) – doubtful species, figure in POBEDINA (1954) cannot be evaluated cornuta n.sp. – Quenselia cornuta corpulentus SUZIN 1968 (Solea) – Callionymidae cottreaui PRIEM 1911 (Solea) – Myctophidae (see NOLF 1985) decipiens STINTON 1966 (Bothus) – doubtful species dominicensis n.sp. – Syacium dominicensis (as Bothidae sp. in NOLF & STRINGER, 1992) dorsolobatus SCHWARZHANS 1980 (Bothidarum) – Taeniopsetta dorsolobata elongatus FROST 1925 (Pleuronectes) – doubtful species, drawing very schematic extremus SCHWARZHANS 1980 (Arnoglossus) – Arnoglossus extremus fangariensis SCHUBERT 1912 (Pleuronectidarum) – doubtful species, type lost, cannot be evaluated from figure flexodorsalis n.sp. – Peltorhamphus flexodorsalis foliformis POBEDINA 1954 (Rhombus) – doubt ful species (see Nolf 1985) fordycei SCHWARZHANS 1980 (Achirus) – Peltorhamphus fordycei frequens STEURBAUT 1984 (Buglossidium) – Microchirus frequens (replaces “Solea approximata” of authors) 16 * * * * * s * * * * * * # * glaber KOKEN 1888 (Solea) – Heterenchelyidae granum SCHWARZHANS 1994 (Aesopia) – Granulithus granum grenfelli n.sp. – Arnoglossus grenfelli guestfalica KOKEN 1891 (Solea) – syn. Rhombocitharus rhenanus heletroides (STINTON ms, in NOLF & CAPETTA 1976) (Bothidarum) – nomen nudum, subesquently described as Bothidarum biaculeatus by NOLF & LAPIERRE 1979 helvecianus JONET 1972 (Pseudorhombus) – Heterenchelyidae (see STEUTBAUT & JONET 1981) holleri WEINFURTER 1952 (Arnoglossus) – Arnoglossus holleri hunyadensis SCHUBERT 1912 (Pleuronectidarum) – doubtful species, type lost, cannot be evaluated from figure ignobilis SCHWARZHANS 1994 (Limanda) – Limanda ignobilis inconspectus SMIGIELSKA 1973 (Arnoglossus) – syn. Arnoglossus taureri irregularis WEILER 1959 (Pleuronectidarum) – doubtful species, not identifiable juvenile pleuronectiform karaganensis SUZIN 1968 (Rhombus) – Callionymidae kirchbergeana H.v.MEYER 1852 (Solea) – Microchirus kirchbergeanus, found “in situ” by WEILER 1955 klockenhoffi GAEMERS & SCHWARZHANS 1982 (Lepidorhombus) – Lepidorhombus klockenhoffi kokeni BASSOLI 1906 (Solea) – Arnoglossus kokeni kokeni SCHUBERT 1906 (Solea) – syn. Dicologlossa patens konkensis SUZIN 1968 (Rhombus) – doubtful species, cannot be evaluated from figure lapierrei NOLF 1988 (Bothidarum) – Arnoglossus lapierrei latior SCHUBERT 1906 (Solea) – Microchirus latior latisulcatus FROST 1924 (Citharus) – Trachinoidei lenticularis KOKEN 1884 (Solea) – Nettastomatidae leuchsi WEINFURTER 1952 (Cynoglossus) – Cynoglossus leuchsi lobata BASSOLI 1906 (Platessa) – Chaunacidae * # s s s * * * * * * * s * * * # (see NOLF & STEURBAUT 1983) longus SCHWARZHANS 1980 (Arnoglossus) – Arnoglossus longus lusitanicus JONET 1972 (Eucitharus) – Citharus lusitanicus medius WEILER 1958 (Phrynorhombus) – Phrynorhombus medius minor SCHUBERT 1906 (Rhombus) – Hemirhamphidae miocenica POBEDINA 1954 (Rhombus) – doubtful species, cannot be evaluated from figure miocenicus WEILER 1942 (Eucitharus) – Citharus sp., based on non-diagnostic juvenile, doubtful species. miocenicus WEILER 1962 (Arnoglossus) – syn. Arnoglossus holleri nolfi n.sp. – Pseudopardachirolithus nolfi novaezeelandiae n.sp. – genus aff. Rhombocitharus novaezeelandiae novus SCHWARZHANS 1980 (Arnoglossus) – Arnoglossus novus obliquoventralis n.sp. – Cynoglossus obliquoventralis obliquus MENZEL 1986 (Bothidarum) – syn. Phrynorhombus medius oedelemensis NOLF 1972 (Psettodes) -syn. Psettodes collatus orbicularis FROST 1933 (Pleuronectidarum) – rejected fragmentary species otomoi HATAI 1965 (Limanda) – doubtful species patens BASSOLI 1906 (Solea) – Dicologlossa patens pentagonalis STEURBAUT 1984 (Pleuronectidarum) – Brachypleura pentagonalis polonica n.sp.- Bathysolea polonica premaxima SHEPHERD 1916 (Psetta) – syn. Genartina hampshirensis, family indeterminable, probably close to Pterothrissidae (NOLF 1985) priscus SCHWARZHANS 1994 (Monolene) – Monolene priscus prudhommae STEURBAUT 1984 (Monolene) – Arnoglossus prudhommae * quadratus n.sp. – Arnoglossus quadratus * radwanskae n.sp. – Grammatobothus radwanskae rharbensis n.sp. – Laeops rharbensis rhenanus KOKEN 1891 (Rhombus) – Rhombocitharus rhenanus rhenanus KOKEN 1891 (sensu SCHUBERT * * * Schwarzhans: Pleuronectiformes 17 * s s * # # * * * s s * # * s 1906) – syn. Lepidorhombus subtriangularis rhenanus KOKEN 1891 (sensu LIEBUS 1927) – from the Upper Cretaceous of Austria, an undescribed Acropomatidae of the fossil genus Plesiopoma (SCHWARZHANS 1995) rhenanus KOKEN 1891 (sensu WEINFURTER 1952) – Citharus lusitanicus rhomboides SCHWARZHANS 1973 (Bothidarum) – Rhombocitharus rhomboides roseni NOLF & CAPETTA 1980 (Paraplagusia) – syn. Cynoglossus leuchsi rosenthalensis WEILER 1942 (Bothus) – Zeugopterus rosenthalensis rotunda PRIEM 1914 (Gobius) – Solea rotunda (STEURBAUT 1984) rotundus SUZIN 1968 (Solea) – doubtful species, not identifiable juvenile pleuronectiform schuberti BASSOLI 1906 (Eucitharus) – Citharus schuberti schultzei NOLF & LAPIERRE 1979 (Soleidarum) – Praearchirolithus schultzei sector KOKEN 1891 (Platessa) – Congridae sectoroides SCHUBERT 1906 (Pleuronectes) – Congridae semen NOLF 1972 (Bothus) – not a pleuronectiform simplex POBEDINA 1954 (Solea) – doubtful species, cannot be evaluated from figure solitarius ROEDEL 1928 (Solea) – rejected species, not identifiable fragmentary otolith, not a pleuronectiform songgoensis VORSTMANN 1927 (Solea) – doubtful species splendens SCHUBERT 1906 (Pleuronectidarum) – Laeops splendens spinosus NOLF 1972 (Psettodes) – syn. Psettodes collatus subglaber SCHUBERT 1906 (Solea) – Heterenchelyidae subrostratus SCHUBERT 1908 (Pleuronectidarum) – Gonostomiatidae (see NOLF & STEURBAUT 1981) subtriangularis HEINRICH 1970 (Lepidorhombus) – Lepidorhombus subtriangularis subvulgaris SCHUBERT 1906 (Solea) – syn. Microchirus kirchbergeanus sulci STEURBAUT 1984 (Solea) – Pseudopardachirolithus sulci syacioides WEINFURTER 1952 (Pleuronectidarum) – Syacium syacioides taureri WEINFURTER 1952 (Solea) – Arnoglossus taureri Piscium Catalogus, Part Otolithi piscium, Vol. 2 * * * * * * * * temputulensis POSTHUMUS 1929 (Pleuronectidarum) – not a pleuronectiform (WEILER 1968) tenuis SCHUBERT 1906 (Solea) – based on unique juvenile specimen, doubtful species, possibly syn. Laeops splendens texana DANTE & FRIZZELL 1965 (Eosolea) – a Heterenchelyidae transitus n.sp. – Cyclopsetta transitus (as Pleuronectiformorum sp. in NOLF, 1976) validus n.sp. – Samaris validus varians STINTON 1966 (Citharichthys) – rejected species (NOLF 1985) vulsus STINTON 1958 (Pleuronectes) – a fragmentary and not identifiable Cepolidae weileri GAEMERS 1972 (Sebastes) – ? syn. Rhombocitharus rhenanus weileri SCHWARZHANS 1974 (Bothidarum) – syn. Rhombocitharus rhenanus weinfurteri n.sp. – Pseudorhombus weinfurteri wienrichi n.sp. – Microchirus wienrichi xenosulcis n.sp. – genus aff. Brachypleura xenosulcis (as Bothidae sp. in NOLF & BAJPAI, 1992) The following is a list of species regarded as doubtful. It contains species based on inconclusive type-material (juvenile and/or eroded types whose status has not been clarified by subsequent findings) or species still needing revision. Type location and formation is added. These names – although nominally valid – should not be used in future descriptions of fossil faunas until revision is carried out or until additional material has been obtained to clarify the status. altus, Rhombus, POBEDINA 1954 from the Upper Miocene of Kazakhstan angulata, Solea, FROST 1925 from the Neogene of Sumatra aomoriensis, Limanda, HATAI 1965 from the Pliocene of Japan balangoensis, Solea, VORSTMANN 1927 from the Upper Eocene of Java contortus, Bothus, FROST 1934 from the Upper Eocene of England corius, Rhombus, CHALIKOV 1946 (in POBEDINA 1954) from the Upper Miocene of Kazakhstan decipiens, Bothus, STINTON 1966 from the Lower Eocene of England 18 elongatus, Pleuronectes, FROST 1925 from the Neogene of Sumatra fangariensis, Pleuronectidarum, SCHUBERT 1912 from the Miocene of Sardinia foliformis, Rhombus, POBEDINA 1954 from the Upper Miocene of Kazakhstan hunyadensis, Pleuronectidarum, SCHUBERT 1912 from the Lower Miocene of Hungary irregularis, Pleuronectidarum, WEILER 1959 from the Lower Miocene of Mexico konkensis, Rhombus, SUZIN 1968 from the Lower Pliocene of Kazakhstan miocenica, Rhombus, POBEDINA 1954 from the Upper Miocene of Kazakhstan miocenicus, Eucitharus, WEILER 1942 from the Lower Miocene of Germany otomoi, Limanda, HATAI 1965 from the Pliocene of Japan rotundus, Solea, SUZIN 1968 from the Lower Pliocene of Kazakhstan simplex, Solea, POBEDINA 1954 from the Upper Miocene of Kazakhstan songgoensis, Solea, VORSTMANN 1927 from the Upper Eocene of Java tenuis, Solea, SCHUBERT 1906 from the Middle Miocene of Austria The following is a compilation of recent species to which fossil specimens have been assigned. Wherever appropriate a revised identification is included. Records regarded as valid are shown in bold print. asperrimum, Clidoderma, (as Lyopsetta cf. exilis in OHE, 1983) -Upper Pliocene of Japan atricaudus, Symphurus, (in FITCH, 1966) – Pleistocene of California bilineata, Paraplagusia, (in OHE, 1981) – Pliocene of Japan boscii, aff., Lepidorhombus, (in NOLF, 1978) – Pliocene of Belgium, an inidentifiable eroded specimen of the genus Lepidorhombus californicus, Paralichthys, (in FITCH, 1964, 1967a, 1970) – Upper Pliocene and Pleistocene of California commersoniana, cf., Synaptura, (in OHE, 1981) – Pliocene of Japan, not a pleuronectiform cornutus, Pleuronichthys, (in OHE, 1981) – Pliocene of Japan cuneata, Dicologlossa (in STEURBAUT & JONET, 1981) – Lower Miocene of Portugal, Dicologlossa patens cuneata, aff., Dicologlossa, (in RADWANSKA, 1992) – Middle Miocene of Poland, Microchirus kirchbergeanus (pars) and Pseudorhombus weinfurteri exilis, Lyopsetta, (in FITCH, 1964, 1967a, 1967b, 1968, 1970) – Upper Pliocene and Pleistocene of California exilis, cf., Lyopsetta, (in OHE, 1983) – Upper Pliocene of Japan, Clidoderma asperrimum ferruginea, aff., Limanda, (in NOLF, 1978) – Pleistocene of Belgium, Limanda limanda flesus, Platichthys, ( in STINTON, 1985) – Pleistocene of southern England hexophthalma, aff., Dicologlossa, (in STEURBAUT & JONET, 1981 and STEURBAUT, 1984) – Miocene of Portugal and SW-France, probably an undescribed species of Quenselia imperialis, Arnoglossus, – Lower Pliocene of Belgium imperialis, aff., Arnoglossus, (in LANCKNEUS & NOLF, 1979) – Upper Miocene of NW-France, an indeterminable juvenile otolith of the genus Arnoglossus isolepis, Isopsetta, (in FITCH, 1970) – Pleistocene of California japonica, Paraplagusia, (in OHE, 1981) – Pliocene of Japan jordani, Eopsetta, (in FITCH, 1967b, 1970) – Pleistocene of California joyneri, cf., Cynoglossus, (in OHE, 1981) – Pliocene of Japan lascaris, Pegusa, (in GAEMERS & SCHWARZHANS, 1973) – Pliocene of Belgium, Microchirus variegatus lascaris, cf., Solea, (in OHE, 1981) – Pliocene of Japan, Heteromycteris sp. laterna, Arnoglossus, (in GAEMERS & SCHWARZHANS, 1973 and NOLF 1978) – Pliocene of Belgium laterna, Arnoglossus, (in ANFOSSI & MOSNA, 1979) – Lower Plicene of Italy, Arnoglossus kokeni laterna, cf., Arnoglossus, (in OHE, 1981) – Pliocene of Japan, Paralichthys aff. olivaceus laterna, Arnoglossus, (in RADWANSKA, 1992) – Middle Miocene of Poland, Arnoglossus taureri limanda, Limanda, (in GAEMERS, 1974 and NOLF, 1978 as Limanda aff. ferruginea) – Pleistocene of Belgium, (in STINTON, 1985) Pleistocene of southern England linguatula, Citharus, (in NOLF & CAPPETTA 1988) – Lower Pliocene of SW-France, Citharus balearicus Schwarzhans: Pleuronectiformes 19 lugubris, cf., Chascanopsetta, (in OHE, 1981, 1983) – Pliocene of Japan, probably an undescribed species of Tarphops luteum, Buglossidium, (in NOLF 1978) – Pliocene of Belgium, probably Microchirus variegatus nigrescens, Symphurus, – Lower Pliocene of NWMorocco olivaceus, aff., Paralichthys, (as Arnoglossus cf. laterna in OHE, 1981) – Pliocene of Japan pacificus, Microstomus, (in FITCH, 1968) – Pleistocene of California panamensis, aff., Cyclopsetta, (as ?Pleuronectidae indet. in NOLF & STRINGER, 1992) – Pliocene of Dominican Republic pavoninus, cf., Pardachirus, (in OHE, 1981) – Pliocene of Japan pentophthalmus, Pseudorhombus, (in OHE, 1981, 1983) – Pliocene of Japan, indeterminable eroded otoliths, possibly of the family Soleidae platessa, Pleuronectes, (in STINTON, 1985) – Pleistocene of southern England platessa, cf., Pleuronectes, (in NOLF, 1978) – Pleistocene of Belgium, indeterminable eroded pleuronectid otolith platessoides, Hippoglossoides, (in GAEMERS, 1974) – Pleistocene of Belgium punctatus, cf., Zeugopteru,s (in NOLF, 1978) – Pliocene of Belgium, cannot be evaluated from figure ritteri, Pleuronichthys, (in FITCH, 1964, 1970) – Pleistocene of California senegalensis, aff. Solea, (in STEURBAUT, 1979) – Miocene of SW-France, single eroded specimen, likely representing Dicologlossa patens solea, Solea, (in RADWANSKA, 1992) – Middle Miocene of Poland, Dicologlossa patens (pars) and Solea rotunda (pars) solea, cf., Solea, (in Ohe, 1981) – Pliocene of Japan, probably a species of the genus Pseudorhombus sordidus, Citharichthys, (in FITCH, 1964, 1967a, b, 1968, 1970) – Upper Pliocene and Pleistocene of California stellatus, Platichthys, (in FITCH, 1970) – Pleistocene of California stenolepis, Hipoglossus, (in FITCH, 1970) – Pleistocene of California stigmaeus, Citharichthys, (in FITCH, 1964, 1967a, b, 1968, 1970) – Upper Pliocene and Pleistocene of California Piscium Catalogus, Part Otolithi piscium, Vol. 2 stomias, Atherestes, (in FITCH, 1968, 1970) – Pleistocene of California tenius, Peltorhamphus, – Lower Pliocene of New Zealand ui, Engyproson, (in OHE, 1981, 1983) – Pliocene of Japan, eroded specimens, probably indeterminable ui, aff., Engyprosopon, (in OHE 1981) – Pliocene of Japan, probably an undescribed species of the genus Tarphops variegatus, Microchirus, (in NOLF, 1978, STINTON, 1985 and GAEMERS & SCHWARZHANS, 1973 as Pegusa lascaris) – Pliocene and Pleistocene of Belgium and southern England variegatus, Microchirus, (in NOLF & CAPPETTA 1988) – Pliocene of France, probably an undescribed species of the genus Microchirus variegatus, aff., Microchirus, (in RADWANSKA, 1992) – Middle Miocene of Poland, Microchirus latior vetulus, Parophrys, (in FITCH, 1964, 1967a, 1968, 1970) – Pleistocene of California vulgaris, Solea, (in STINTON, 1985) – Pleistocene of southern England whiffiagonis, Lepidorhombus, (in GAEMERS & SCHWARZHANS, 1973) – Pliocene of Belgium xanthostigma, Citharichthys, (in FITCH, 1968, 1970) – Pleistocene of California zachirus, Glyptocephalus, (in FITCH, 1967b, 1968, 1970) – Pleistocene of California In the following summary-list all fossil records accepted as valid are compiled in their current systematic position. The list contains both fossil otolith based species as well as recent species which have been recorded as fossils. It also includes stratigraphic and geographic distributions. Psettodidae Psettodes collatus NOLF 1972 – Middle Eocene of Belgium genus aff. Psettodes bavayi (NOLF 1988) – Lower Eocene of France (Aquitaine Basin) Citharidae Citharus balearicus BAUZA RULLAN 1955 – Upper Pliocene of Mallorca (Spain) and Lower Pliocene of SW-France and Morocco Citharus lusitanicus JONET 1972 – Lower to Middle Miocene of Portugal, France (Aquitaine Basin), Austria and Poland (both Paratethys) Citharus schuberti BASSOLI 1906 – Upper Miocene and Lower Pliocene of Italy 20 Paracitharus angustus (SCHWARZHANS 1978) – Lower Pliocene of Italy Rhombocitharus biaculeatus (NOLF & LAPIERRE 1979) – Middle Eocene of Belgium and England Rhombocitharus cauneillensis (NOLF 1988) – Upper Eocene of France (Aquitaine Basin) Rhombocitharus circularis (STINTON 1966) – Lower Eocene of England and France (Aquitaine Basin) Rhombocitharus rhenanus (KOKEN 1891) – Middle and Upper Oligocene of northern Germany and Mainz Basin Rhombocitharus rhomboides (SCHWARZHANS 1973) – Lower Miocene of northern Germany genus aff. Rhombocitharus novaezeelandiae n.sp. – Upper Oligocene of New Zealand. Brachypleuridae Brachypleura pentagonalis (STEURBAUT 1984) – Lower Oligocene of France (Aquitaine Basin) genus aff. Brachypleura xenosulcis n.sp. – Upper Eocene of Java Scophthalmidae Lepidorhombus angulosus NOLF 1976 – Lower and Middle Miocene of Belgium and northern Germany Lepidorhombus klockenhoffi GAEMERS & SCHWARZHANS 1982 – Upper Miocene of northern Germany Lepidorhombus subtriangularis HEINRICH 1970 – Upper Oligocene to Middle Miocene of northern Germany, Middle Miocene of Austria and Poland Lepidorhombus whiffiagonis (WALBAUM 1792) – Recent species, also known from the Lower Pliocene of Belgium Zeugopterus rosenthalensis (WEILER 1942) – Upper Oligocene of northern Germany Zeugopterus cf. punctatus (BLOCH 1787) – Recent species, also known from the Lower Pliocene of Belgium Phrynorhombus medius WEILER 1958 – Lower to Upper Miocene of northern Germany Bothidae Paralichthys californicus (AYRES 1862) – Recent species, also known from the Upper Pliocene and Pleistocene of California Paralichthys aff. olivaceus (TEMMINCK & SCHLEGEL 1846) – Recent species, also known from the Pliocene of Japan Pseudorhombus weinfurteri n.sp. – Middle Miocene of Austria Cyclopsetta aff. panamensis (STEINDACHNER 1875) – Recent species, also known from the Pliocene of Dominican Republic Cyclopsetta transitus n.sp. – Lower Miocene of Trinidad Syacium dominicensis n.sp. – Upper Miocene of Domonican Republic Syacium syacioides (WEINFURTER 1952) – Middle Miocene of Austria Citharichthys sordidus (GIRARD 1856) – Recent species, also known from the Upper Pliocene and Pleistocene of California Citharichthys stigmaeus JORDAN & GILBERT 1883 – Recent species, also known from the Upper Pliocene and Pleistocene of California Citharichthys xanthostigma GILBERT 1890 – Recent species, also known from the Pleistocene of California Etropus concaviventris n.sp. – Upper Miocene of Dominican Republic Grammatobothus awamoaensis n.sp. – Lower Miocene of New Zealand Grammatobothus radwanskae n.sp. – Middle Miocene of Poland Arnoglossus extremus SCHWARZHANS 1980 – Upper Eocene of New Zealand Arnoglossus grenfelli n.sp. – Lower Pliocene of New Zealand Arnoglossus holleri WEINFURTER 1952 – Lower and Middle Miocene of northern Germany, Lower and Middle Miocene of Austria, Poland, Portugal and SW-France Arnoglossus imperialis (RAFINESQUE 1810) – Recent species, also known from the Lower Pliocene of Belgium Arnoglossus kokeni (BASSOLI 1906) – Upper Miocene of Italy, Lower Pliocene of Morocco and southern France and Pliocene of Spain Arnoglossus lapierrei NOLF 1988 – Lower Eocene of France (Aquitaine Basin) Arnoglossus laterna (WALBAUM 1792) – Recent species, also known from the Lower and Upper Pliocene of Belgium Arnoglossus longus SCHWARZHANS 1980 – Upper Oligocene and Lower Miocene of New Zealand Arnoglossus novus SCHWARZHANS 1980 – Lower and Middle Miocene of New Zealand Arnoglossus prudhommae (STEURBAUT 1984) – Lower Oligocene of France (Aquitaine Basin) Schwarzhans: Pleuronectiformes 21 Arnoglossus quadratus n.sp. – Lower Pliocene of NW-Morocco Arnoglossus taureri (WEINFURTER 1952) – Lower and Middle Miocene of Austria, Poland and Portugal Caulopsetta arnoglossoides n.sp. – Lower Miocene of New Zealand Taeniopsetta dorsolobata (SCHWARZHANS 1980) – Lower Miocene of New Zealand Laeops splendens (SCHUBERT 1906) – Middle Miocene of Austria and Poland Laeops rharbensis n.sp. – Lower Pliocene of NWMorocco Monolene priscus SCHWARZHANS 1994 – Upper Oligocene of northern Germany fornia Microstomus pacificus (LOCKINGTON 1878) – Recent species, also known from the Pleistocene of California Pleuronichthys cornutus (TEMMINCK & SCHLEGEL 1846) – Recent species, also known from the Pliocene of Japan Pleuronichthys ritteri STARKS & MORRIS 1907 – Recent species, also known from the Pleistocene of California Isopsetta isolepis (LOCKINGTON 1881) – Recent species, also known from the Pleistocene of California Samaris validus n.sp. – Lower Pliocene of New Zealand Pleuronectidae Eopsetta jordani (LOCKINGTON 1880) – Recent species, also known from the Pleistocene of California Hippoglossus stenolepis SCHMIDT 1904 – Recent species, also known from the Pleistocene of California Atherestes stomias (JORDAN & GILBERT 1881) – Recent species, also known from the Pleistocene of California Hippoglossoides platessoides (FABRICIUS 1780) – Recent species, also known from the Pleistocene of Belgium Lyopsetta exilis (JORDAN & GILBERT 1881) – Recent species, also known from the Upper Pliocene and Pleistocene of California Glyptocephalus zachirus LOCKINGTON 1878 – Recent species, also known from the Pleistocene of California Clidoderma asperrimum (TEMMINCK & SCHLEGEL 1846) – Recent species, also known from the Upper Pliocene of Japan Limanda ignobilis SCHWARZHANS 1994 – Upper Oligocene of northern Germany Limanda limanda (LINNAEUS 1758) – Recent species, also known from the Pleistocene of Belgium and England Parophrys vetulus GIRARD 1856 – Recent species, also known from the Pleistocene of California Pleuronectes platessa LINNAEUS 1758 – Recent species, also known from the Pleistocene of England Platichthys flesus (LINNAEUS 1758) – Recent species, also known from the Pleistocene of England Platichthys stellatus (PALLAS 1787) – Recent species, also known from the Pleistocene of Cali- Soleidae Microchirus frequens (STEURBAUT 1984) – Upper Oligocene and Lower Miocene of France (Aquitaine Basin), Upper Oligocene (?to Upper Miocene) of northern Germany, Belgium and the Netherlands Microchirus kirchbergeanus (H.v.MEYER 1852) – known from otoliths and skeletons with otoliths “in situ” from the Middle Miocene of Bavaria, Austria, Poland and the Lower Miocene of Portugal Microchirus latior (SCHUBERT 1906) – Lower and Middle Miocene of Austria Microchirus variegatus (DONOVAN 1802) – Recent species, also known from the Pliocene and Pleistocene of Belgium and England Microchirus wienrichi n.sp. – Lower and Middle Miocene of northern Germany, Belgium and the Netherlands Dicologlossa patens (BASSOLI 1906) – Lower to Upper Miocene of Italy, Austria, France and Portugal Quenselia cornuta n.sp. – Lower Pliocene of NWMorocco and possibly also Upper Miocene of Portugal Solea rotunda (PRIEM 1914) – Lower Miocene of France (Aquitaine Basin), Middle Miocene of Poland Solea vulgaris QUENSEL 1806 – Recent species, also known from the Pleistocene of England Bathysolea polonica n.sp. – Middle Miocene of Poland Granulithus granum SCHWARZHANS 1994 – Upper Oligocene of northern Germany Praearchirolithus schultzei NOLF & LAPIERRE 1979 – Upper Eocene of France (Paris Basin) Piscium Catalogus, Part Otolithi piscium, Vol. 2 22 Pardachirus cf. pavoninus (LACEPEDE 1802) – Recent species, also known from the Pliocene of Japan Pseudopardachirolithus nolfi n.sp. – Upper Eocene of France (Paris Basin) Pseudopardachirolithus sulci STEURBAUT 1984 – Upper Oligocene and Lower Miocene ofFrance (Aquitaine Basin) Peltorhamphus flexodorsalis n.sp. – Lower Pliocene of New Zealand Peltorhamphus fordycei (SCHWARZHANS 1980) – Middle Miocene of New Zealand Peltorhamphus tenuis JAMES 1972 – Recent species, also known from the Lower Pliocene of New Zealand Cynoglossidae Cynoglossus (Paraplagusia) bilineata (BLOCH 1785) – Recent species, also known from the Pliocene of Japan Cynoglossus (Paraplagusia) japonica (TEMMINCK & SCHLEGEL 1846) – Recent species, also known from the Pliocene of Japan Cynoglossus cf. joyneri GÜNTHER 1878 – Recent species, also known from the Pliocene of Japan Cynoglossus leuchsi WEINFURTER 1952 – Lower and Middle Miocene of Austria, France (Aquitaine and Mediterranean Basins), Portugal and northern Germany Cynoglossus obliqueventralis n.sp. – Lower Pliocene of NW-Morocco Symphurus atricaudus (JORDAN & GILBERT 1880) – Recent species, also known from the Pleistocene of California Symphurus nigrescens RAFINESQUE 1810 – Recent species, also known from the Lower Pliocene of NW-Morocco 4.3 Distribution of fossil pleuronectiform faunas based on otolith findings Miocene and Pliocene – Mexico, Trinidad and Dominican Republic. References: WEILER 1959, NOLF 1976, NOLF & STRINGER 1992. Pleuronectiform otoliths seem to be quite common and specious in these sediments judging from the amount of taxa recorded from just a few localities. WEILER (1959) described a genus Pleuronectidarum irregularis from the Lower Miocene of Mexico. This species, however, was based on juvenile otoliths without really diagnostic characters and should be regarded as a doubtful species for the time being. NOLF (1976) left four species, from various Miocene strata of Trinidad, in open nomenclature, because he felt that not enough recent pleuronectiform otoliths were known from the area. This situation has changed now. One species from the Lower Miocene is here described as Cyclopsetta transitus (as genus Pleuronectiformorum sp.1 in NOLF 1976). The others are too poorly preserved for specific identification. They represent Citharichthys sp., an unidentifiable bothid and a species of Symphurus. The material described by NOLF & STRINGER (1992) from the Upper Miocene and Pliocene of the Dominican Republic contains five pleuronectiforms, which they likewise left in open nomenclature. Three of them are described here as Cyclopsetta aff. panamensis (as ?Pleuronectidae indet. in NOLF & STRINGER 1992) from the Pliocene, Syacium dominicensis (as Bothidae indet.) from the Upper Miocene and Etropus concaviventris also from the Upper Miocene. In addition there are two unidentifiable species, one of the genus Symphurus and a soleid of the genus Achirus (as Soleidae indet.) both from the Upper Miocene. This short list documents the potential for future discoveries of pleuronectiform otoliths in the general area. From my colleague A. MÜLLER I was informed that a number of pleuronectiform otoliths have also surfaced during his ongoing research in Neogene strata of the Atlantic coast of the United States and the Miocene of Ecuador. 4.3.1 North and Middle America 4.3.2 Europe Pliocene and Pleistocene – California. References: FITCH (div.). In various publications FITCH has reported a total of 15 otolith based pleuronectiform species from the Pliocene and Pleistocene of California. They all represent living species from that region. The largest number of fossil pleuronectiform otoliths until now has been described from the European younger Tertiary. This is an artificial situation reflecting only the high level of investigation this area has received in the past. Once other Schwarzhans: Pleuronectiformes 23 areas have been studied more extensively there will undoubtedly be a shift of importance to such areas as Middle America or the Far East (Japan, China and Indonesia). The taxonomic status of many of the pleuronectiform otolith records from Europe is badly in need of revision (as indicated above), in particular the many secondary references and specimens left in open nomenclature in more recent literature. I have reviewed a fair proportion of type- and non-type-material from a considerable number of locations. However, the taxonomic summary presented below must still be regarded as incomplete. This is particularly true as far as the geographic and stratigraphic distribution of the various species is concerned. Eocene – Belgium, Great Britain and France References: FROST 1934, STINTON 1966, NOLF 1972a,b, NOLF & CAPPETTA 1976, NOLF & LAPIERRE 1979, NOLF 1988. Lower to Upper Eocene strata from Belgium, Great Britain and France have yielded the earliest otolith records of the Pleuronectiformes. Most otoliths represent very plesiomorphic genera. Psettodidae such as Psettodes collatus from the Middle Eocene of Belgium and genus aff. Psettodes bavayi from the Lower Eocene of the Aquitaine Basin (France) are typical representatives as well as the fossil citharid genus Rhombocitharus with the three species – R. circularis (Lower Eocene, London Basin and Aquitaine Basin), R. biaculeatus (Middle Eocene of Belgium and England) and R. cauneillensis (Upper Eocene of the Aquitaine Basin). The Bothidae are represented by Arnoglossus lapierrei. Finally, there are two records of the Soleidae, both from the Pardachirus Group – Praearchirolithus schultzei and Pseudopardachirolithus nolfi – both from the Upper Eocene of the Paris Basin. Although representing typical Pleuronectiformes these earliest otolith records are interpreted as being relatively close to the “root” of flatfishes phylogenetically, as indicated by their very plesiomorphic features. However, the Arnoglossus species and the two species of the Pardachirus Group already exhibit a surprisingly “modern” otolith morphology. In any case, they confirm the presence of true Pleuronectiformes as far back as the early Tertiary. Likewise, the earliest skeletonbased fossil records of the order Pleuronectiformes date back to the Middle Eocene at least (see NORMAN 1934 and ANDREWS, GARPiscium Catalogus, Part Otolithi piscium, Vol. 2 DINER, MILES & PATTERSON 1967), where they are represented by Psettodidae s.l., Bothidae and Soleidae. Oligocene and Neogene – North Sea Basin (Belgium, Netherlands and Germany). References: KOKEN 1884, 1891, WEILER 1942, 1958, 1962, HEINRICH 1970, GAEMERS 1972, 1974, SCHWARZHANS 1973, 1974, 1977, 1994, GAEMERS & SCHWARZHANS 1973, 1982, NOLF 1976, 1978, NOLF & SMITH 1983, MENZEL 1986, MÜLLER 1994. Throughout the Tertiary of the North Sea Basin pleuronectiform otoliths generally are rare to very rare, but in some strata they are still represented by a surprising number of taxa. Their record in the North Sea Basin proper begins in the Lower Oligocene with a representative of the fossil genus Rhombocitharus (Citharidae) – R. rhomboides. Their record of this lineage continues into Middle and Upper Oligocene times with the well known R. rhenanus, and then terminates. Sediments of the Upper Oligocene are the first to contain a larger number of species. In view of the then isolated situation of the North Sea Basin the origin of the fauna is not very clear. Immigration from the Tethys via Upper Rhine Valley and Mainz Basin does not seem to have played a major role. The oceanic connection to the Arctic Basin newly established in the course of late Eocene to Oligocene history is well established geologically, but can not be evaluated biogeographically due to the total lack of any fossil otoliths from the far northern latitudes. In any case, the indigenous character of the Oligocene Teleost fauna of the North Sea Basin becomes evident immediately, when a comparison is made with contemporary faunas of the European Atlantic Basins (STEURBAUT 1984, SCHWARZHANS 1994). The Upper Oligocene contains the following taxa (see SCHWARZHANS 1994 for the most recent review): Citharidae: Rhombocitharus rhenanus; Scophthalmidae: Lepidorhombus subtriangularis, Zeugopterus rosenthalensis; Bothidae: Monolene priscus and an additional bothid (gen. and spec. indet.); Pleuronectidae: Limanda ignobilis; Soleidae: Microchirus frequens (replacement for the rejected Solea approximata), Granulithus granum (the latter indicative of rocky nearshore environments). During Miocene north of Scotland a new connection became established between the North Sea and the East Atlantic. This opening facilitat- 24 ed to a certain extend the faunal exchange between of the two regions, which had been impossible during Oligocene times. Probable immigrants into the North Sea Basin include Cynoglossus leuchsi and Citharus sp. The latter was originally described by WEILER (1942) as Eucitharus miocenicus. However, his unique type-specimen was a juvenile lacking characters of true diagnostic value and thus the species must at present be regarded as of doubtful nature. Lepidorhombus subtriangularis and possibly also Arnoglossus holleri were probable emigrants from the North Sea Basin. Lepidorhombus angulosus appears to have been restricted to the North Sea Basin, as was still another scophthalmid – Phrynorhombus medius. Microchirus wienrichi is also restricted to the Miocene of the North Sea Basin. The occurrence of Microchirus frequens in the Miocene of the North Sea Basin remains somewhat questionable (including the type of the now rejected Solea approximata, see entry to M. frequens for detailed discussion). A third Lepidorhombus species is known from the Upper Miocene – L. klockenhoffi – replacing L. angulosus of the Lower and Middle Miocene. Plio-/Pleistocene records of flatfish otoliths from the North Sea Basin have been placed into recent species from the same region. From the Pliocene the following species are here accepted as valid: Lepidorhombus whiffiagonis, Zeugopterus cf. punctatus, Arnoglossus laterna, Arnoglossus imperialis, Microchirus variegatus and Solea vulgaris. The first “modern” pleuronectids reported from the North Sea Basin are Hippoglossoides platessoides from the Pleistocene of Belgium and Limanda limanda, Pleuronectes platessa and Platichthys flesus from the Pleistocene of southern England. In view of their abundance in the Recent North Sea this very late appearance of a Pleuronectidae is particularly amazing. In summary, the North Sea Basin contained a rich flatfish faunal component since Oligocene times at least, although abundance of otoliths is much less than would be expected from the present day picture. Some fossil taxa relate well to the recent fauna, for instance the Scophthalmidae, Arnoglossus of Bothidae or Microchirus of Soleidae, others do not (particularly in respect to the lack of fossil Pleuronectidae). In total 19 species are accepted as valid records from the Oligocene to the Pleistocene. There are 7 fossil species from the Oligocene and 8 from the Miocene (2 of which occurring in both strata). 6 species recorded from the Plio-/Pleistocene all represent extant species. Oligocene – Mainz Basin (Germany). References: KOKEN 1891, SCHWARZHANS 1994. Rhombocitharus rhenanus (Citharidae) from the Middle Oligocene is the only pleuronectiform recorded so far from this small basin. For a short period during the Middle Oligocene a marine fairway led through the Mainz Basin connecting the North Sea Basin to the Bavarian Basin and the Paratethys. R. rhenanus represents a lineage well known from the North Sea since at least Early Oligocene times. Its occurrence in the Mainz Basin is therefore regarded as due to immigration from the north. Oligocene and Miocene – Atlantic Basins (France and Portugal). References: PRIEM 1914, JONET 1973, LANCKNEUS & NOLF 1979, STEURBAUT 1979, 1984, STEURBAUT & JONET 1981. The Aquitaine Basin in SW-France and the Lusitanian Basin in Portugal have yielded a comparatively rich flatfish otolith fauna, representing practically every family except for the Pleuronectidae. 16 species are tentatively regarded as valid. From Lower Oligocene strata of the Aquitaine Basin 5 species have been recorded: Brachypleura pentagonalis (Brachypleuridae), Citharus sp. (also Upper Oligocene and Lower Miocene) and an undescribed species of the genus Rhombocitharus (as genus Bothidarum sp. in STEURBAUT 1984), both members of the Citharidae, Arnoglossus prudhommae and a possible Bothus. The Upper Oligocene strata of the Aquitaine Basin are less rich: except for Citharus sp. (see above) they have yielded Pseudopardachirolithus sulci and a second soleid, Microchirus frequens. Lower Miocene pleuronectiform are known from both the Aquitaine and the Lusitanian Basin. Otoliths that I had collected from the typelocalities in the Lusitanian Basin contained two Arnoglossus species, A. taureri and A. holleri, one citharid, Citharus lusitanicus, three soleids, Dicologlossa patens, Microchirus kirchbergeanus and an undescribed species of Quenselia and one cynoglossid, Cynoglossus leuchsi. – The Lower and Middle Miocene from the Aquitaine Basin is richer in pleuronectiforms: Psettodes sp., Citharus lusitanicus, Arnoglossus holleri, Microchirus frequens, an undescribed Quenselia, Pseudopardachirolithus Schwarzhans: Pleuronectiformes 25 sulci, Solea rotunda, Dicologlossa patens and Cynoglossus leuchsi. Arnoglossus taureri seems to be missing and Microchirus kirchbergeanus may be replaced by Microchirus frequens (if these two species can really be reliably differentiated). The Miocene pleuronectiform assemblages from the Atlantic European Basins bear a remarkable resemblance to the contemporary fauna of the northern Paratethys. Except for Solea rotunda and Pseudopardachirolithus sulci which are indigenous to the Aquitaine Basin and Microchirus frequens, which might be an immigrant from the North Sea Basin, all these species are likewise known from the Paratethys. Cynoglossus leuchsi, a species that has been described under a different name from each basin where it occurs, has even migrated into the North Sea. Citharus lusitanicus, an Arnoglossus sp. and a species tentatively assigned to Quenselia cornuta (described as new from the Lower Pliocene of Morocco) are obtained from the Upper Miocene of Portugal. Upper Miocene and Pliocene – Mediterranean (Spain, France and Italy). References: BASSOLI 1906, SANZ ECHEVERRIA 1950, BAUZA RULLAN 1955, SCHWARZHANS 1978, 1986, ANFOSSI & MOSNA 1979, NOLF & MARTINELL 1980, NOLF & CAPPETTA 1980, 1988, NOLF & STEURBAUT 1983. From the Upper Miocene of the Mediterranean 4 species are accepted as valid: Citharus schuberti, Arnoglossus kokeni, Dicologlossa patens and Cynoglossus leuchsi. There is also a possibly undescribed Microchirus (as Solea sp. in NOLF & CAPPETTA 1980 and as Buglossidium sp. in NOLF & STEURBAUT 1983). The Lower Pliocene has yielded two species of Citharus – C. schuberti and C. balearicus – and in addition a third citharid – Paracitharus angustus. Other species recorded are Arnoglossus kokeni (also described as A. bauzai from the Late Pliocene), Dicologlossa patens and Microchirus sp. (as M. variegatus in NOLF & CAPETTA 1988). The richness in citharids probably reflects the predominance of deeper marine sediments from which most of the described faunas have been collected. In particular Citharus schuberti may very well represent a deep water species replacing the more shallow Citharus balearicus. Paracitharus angustus was found in a true deep water sediment deposited below at least 500 m water depth. It represents a genus nowadays endemic to waters around South Africa. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Miocene – Vienna, Pannonian and Bavarian Basins (Austria, Hungary, Czechia, Slovakia, southern Poland and southern Germany). References: SCHUBERT 1906, 1912, WEINFURTER 1952a,b, WEILER 1955, SMIGIELSKA 1973, NOLF 1981, RADWANSKA 1984, 1992, REICHENBACHER 1988. Middle Miocene sediments (Badenian) of these basins, which represent the northern portion of the former Paratethys have proven to be relatively rich in pleuronectiform otoliths. The following 15 species are accepted as valid: Citharidae: Citharus lusitanicus; Scophthalmidae: Scophthalmus sp., Lepidorhombus aff. subtriangularis; Bothidae: Pseudorhombus weinfurteri, Syacium syacioides, Laeops splendens, Arnoglossus holleri, Arnoglossus taureri, Grammatobothus radwanskae; Soleidae: Microchirus kirchbergeanus, Microchirus latior, Solea rotunda, Bathysolea polonica, Dicologlossa patens; Cynoglossidae: Cynoglossus leuchsi. Lepidorhombus aff. subtriangularis and Arnoglossus holleri might have been immigrants from the North Sea Basin, whereas Pseudorhombus, Syacium, Grammatobothus and Laeops probably have southern links judging from the recent distribution pattern of the genera. Most other species except for Microchirus latior have been found widely distributed throughout Miocene European sediments. The Middle Miocene of the northern Paratethys thus ranks as one of the richest fossil pleuronectiform faunas known so far. From the Lower Miocene (Ottnangian and Eggenburgian) only 2 species have been recorded so far: Microchirus latior and Microchirus kirchbergeanus both members of the family Soleidae, the latter also known from otoliths “in situ”. Upper Miocene and Lower Pliocene – Caspi Basin (Kazakhstan) References: POBEDINA 1954, SUZIN 1968. The fauna from the southern Paratethys is of great interest both biogeographically and historically as far as the roots of the present day endemic Caspian fish fauna are concerned. POBEDINA and SUZIN described no less than 9 otolithbased species which they regarded as some kind of pleuronectiform (mostly placed in Rhombus and Solea). I was not able to investigate their typematerial and, unfortunately, their drawings are not detailed enough to permit an interpretation or even review. It seems that many species were based on juveniles and therefore must be regarded as of doubtful identity. At least two are not 26 pleuronectiforms. In only one case I feel confident that the figured specimen might indeed be a good and diagnostically valid pleuronectiform otolith, possibly a pleuronectid. This is “Rhombus” altus POBEDINA 1954. Although the number of species is certainly exaggerated there may very well be additional pleuronectiform representatives amongst the other “more doubtful” species. 4.3.3 NW-Africa Lower Pliocene – NW-Morocco. So far very little is known of the fossil otoliths from Africa. A still largely undescribed fauna from the Lower Pliocene of the Rharb Embayment in NW-Morocco has yielded a relatively rich pleuronectiform assemblage with 7 species: Citharidae: Citharus balearicus; Bothidae: Arnoglossus kokeni, Arnoglossus quadratus, Laeops rharbensis; Soleidae: Quenselia cornuta; Cynoglossidae: Cynoglossus obliqueventralis, Symphurus nigrescens (also Recent in the area). Two species, namely Citharus balearicus and Arnoglossus kokeni, are also known from time equivalent sediments of the European Mediterranean Basin. All the other species seem to be indigenous to NW-Africa. To me, this comes as a surprise, since from the geographical location of the Rharb Embayment close to the Strait of Gibraltar one certainly would have expected a much closer correspondence between the two faunas. Similar observations, however, have been made with other Teleost groups represented in both faunas: Pterothrissidae (SCHWARZHANS 1981), Myctophidae and Acropomatidae (SCHWARZHANS 1986) and Sciaenidae (SCHWARZHANS 1993). The most likely explanation for this phenomenon in my opinion is that the subtropical temperature belt, which today is sharply limited south of the Canary Cold Water Current (Mauritania), extended in Early Pliocene times much further to the north to somewhere between the Rharb Embayment and the Strait of Gibraltar. This interpretation is supported by the close relation of the Lower Pliocene otoliths from the Rharb Embayment with the Recent ones from tropical West Africa. Still the degree of persistent species from Early Pliocene times is amazingly low in all the Teleost groups so far analysed. It thus seems quite possible that the Lower Pliocene Teleost fauna from NW-Morocco represents an extinct biogeographical subprovince of the former West-African bioprovince that vanished after the establishment of the Canary Cold Water Current. 4.3.4 Indopacific References: FROST 1925, VORSTMANN 1927, POSTHUMUS 1929, HATAI 1965, OHE 1981, 1983, NOLF & BAJPAI 1992. Fossil otoliths from Indonesia and Japan have been described rather erratically. Some have been allocated to the Pleuronectiformes, but they all need thorough revision. Unfortunately, I was not in a position to inspect most of the specimens, except for the ones described by NOLF & BAJPAI from the Upper Eocene of Java. They are redescribed here as genus aff. Brachypleura xenosulcis. The remainder of this Indopacific summary forms a very preliminary review. VORSTMANN (1927) described three fossil pleuronectiform otolith species from the Upper Eocene of Java. One of these apparently represents a member of the family Congridae (Anguilliformes), the two other can not be evaluated from his figures. POSTHUMUS (1929) and FROST (1925) recorded a total of three pleuronectiform species from the Neogene of Sumatra. The one described by POSTHUMUS is probably not a pleuronectiform. The figures of the two other species by FROST are so poor that it is impossible to say whether or not they represent pleuronectiforms at all. The indications are that, the Indonesian Tertiary is relatively rich in pleuronectiform otoliths, but the unfortunate situation with FROST’s, VORSTMANN’s and POSTHUMUS’ early publications prohibits any further interpretation of the data. Pleuronectiform otoliths also seem to be quite common in the Pliocene of Japan. HATAI (1965) described two fossil species. His photographs are so minute and of such poor quality that any evaluation of his data without review of the original material is impossible. Subsequently OHE (1981, 1983) described a further series of pleuronectiform otoliths from the Pliocene of Japan. He placed all of his fossil specimens into recent taxa, some even in taxa now restricted to European waters. Those allocations are at least highly suspect and judging from his photographs they are indeed erroneous. Some of the other allocations, many based on eroded or juvenile specimens, are doubtful as well. Judging from his figures I have tentatively accepted the following species as valid (OHE’s interpretations are included in brackSchwarzhans: Pleuronectiformes 27 ets): Bothidae: Paralichthys aff. olivaceus (as Arnoglossus cf. laterna), Pseudorhombus sp. (as Solea cf. solea), Tarphops (n.)sp. (as Chascanopsetta cf. lugubris and Pseudorhombus pentophthalmus); Pleuronectidae: Clidoderma asperrimum (as Lyopsetta cf. exilis), Pleuronichthys cornutus; Soleidae: Pardachirus cf. pavoninus; Cynoglossidae: Cynoglossus bilineata, Cynoglossus japonica, Cynoglossus cf. joyneri. 4.3.5 New Zealand References: SCHWARZHANS 1980 (1984), GRENFELL 1984. Pleuronectiform otoliths are not uncommon in the Tertiary strata of New Zealand. In fact, some of the Neogene species can be quite common at locations. FROST and STINTON (various publications) have been the first to report fossil flatfish otoliths from New Zealand and Australia, but an in-depth revision of their type-material (SCHWARZHANS 1980) has revealed that none represents a true pleuronectiform. Nevertheless, species described by SCHWARZHANS, by GRENFELL and those described as new in the descriptive section which follows, amount to a total of 11 species. The earliest record is Arnoglos- sus extremus from the Upper Eocene. The next is Arnoglossus longus in the Upper Oligocene and Lower Miocene. Five additional bothids occur in the Lower Miocene – genus aff. Rhombocitharus novaezeelandiae, Grammatobothus awamoaensis, Arnoglossus novus (also known from the Middle Miocene), Caulopsetta arnoglossoides and Taeniopsetta dorsolobata. In the Lower and Middle Miocene the first representatives occur of those endemic genera which nowadays are so characteristic for New Zealand – Caulopsetta arnoglossoides and Peltorhamphus fordycei. The richest assemblage so far is recorded from the Lower Pliocene with Arnoglossus grenfelli, Pelotretis sp., Samaris validus, Peltorhamphus flexodorsalis and Peltorhamphus tenuis. Of these, Arnoglossus and Samaris are not now represented in the New Zealandian fauna. Peltorhamphus tenuis represents a recent species from New Zealand and is now also evident from the Lower Pliocene. In contrast to the relatively rich fossil pleuronectiform fauna from New Zealand, the Tertiary strata from southern Australia have so far not yielded a single flatfish otolith (SCHWARZHANS 1985). However, these sediments have not been searched for otoliths quite as extensively. 5. Phylogenetic usage of Pleuronectiformes otoliths 5.1 Characterisation of Pleuronectiformes otoliths Otoliths of the order Pleuronectiformes are characterised by the circumsulcal depression (for explanation see chapter 6.1.). This character may not always be very distinctively developed or it may be disrupted behind the caudal tip, but it remains the only true synapomorphic character found in all otoliths of this order. Otherwise, pleuronectiform otoliths show a bipartite sulcus divided into an ostium and a cauda (with very few exceptions). Proportions of ostium and cauda are variable. Usually, the ostium is longer than the cauda, but in some groups (Psettodidae, Citharidae, Tephrinectes, Paralichthodes, Ammotretis Group) it is shorter or equal in length. The ostium may open anteriorly, but more commonly its opening is pseudoostial or comPiscium Catalogus, Part Otolithi piscium, Vol. 2 pletely reduced. The cauda is usually straight and not particularly narrower than the ostium, but in Psettodidae, Tephrinectes, Paralichthodes and few other genera it is distinctly narrower and with a somewhat inclined tip. 5.2 The origin of the Pleuronectiformes and their outgroup relationship Since REGAN (1913) and NORMAN (1934) the Pleuronectiformes have been understood as being derived from some kind of percoid ancestor. This view has remained unchanged since then. NORMAN (1934) has discussed at length his reasoning for regarding them as related to the Perciformes putting particular emphasis on the analysis of the genus Psettodes (Psettodidae), which he regarded as the most primitive representative 28 of the flatfishes. He found that “apart from the asymmetry and the long dorsal and anal fins, Psettodes might almost be placed in the percoid family Serranidae”. Amongst other characters, he used otolith evidence as illustrated by FROST (1930). Analyses of the otolith morphology strongly support this concept of Psettodes relationships. And otoliths of the genus Psettodes are indeed amongst the most plesiomorphic of the order (other plesiomorphic looking otoliths being the ones of Tephrinectes, Paralichthodes, the Ammotretis Group and the Citharidae s.s.). Psettodes otoliths are characterised by the following features regarded as plesiomorphic: – the distinct anterior opening of the sulcus; – the cauda being longer and considerably narrower than the ostium; – the cauda showing an inclined caudal tip; – the circumsulcal depression being disrupted behind the caudal tip. This kind of otolith morphology is found in many “basal” Percoidei as well. The only character distinguishing Psettodes from any percoid and combining it with the rest of the Pleuronectiformes is the presence of the (yet incomplete) circumsulcal depression. FROST (1930) appreciated the close resemblance of percoid and psettodid otoliths stating that “the otolith of Psettodes erumei resembles in every feature those of the suborder Percoidea”. In particular he found a good relation with otoliths of the Percidae and Centropomidae. SCHWARZHANS (1978, 1980) also argued that the otolith morphology of primitive Pleuronectiformes (of the Psettodidae) most likely derived from some percoid ancestor. I then found particularly close resemblance between otoliths of Psettodes and those of certain genera of Centrarchidae (a freshwater percoid family of North America) and wrote that “Micropterus and Psettodes can hardly be distinguished on the generic level”. Later (1995) I hypothesised that the circumsulcal depression of pleuronectiform otoliths (in particular its ventral part) may have originated from the “doubled” ventral line seen in certain basal Percoidei (for instance Acropomatidae or Centrarchidae). – In conclusion, the close correspondence between the otoliths of the Psettodidae and those of “basal” percoids, together with the indications from psettodid otolith morphology of their most plesiomorphic position among flatfishes, lend strong support to the concept of Pleuronectiformes having derived from a percoid ancestor. However, it may be premature at this stage to speculate which family or “group” of percoids would represent the closest relative. Apart from the percoid relationship of the Psettodidae it has been debated in the ichthyological literature, whether the Pleuronectiformes as a whole represent a truly monophyletic unit or a polyphyletic assemblage. Each of the three suborders (Psettodoidei, Pleuronectoidei and Soleoidei) have been suspected of having originated independently and from “different parts” of a percoid stock. NORMAN (1934) discussed this matter at length and reached the conclusion that “the evidence suggests that the Heterosomata (Pleuronectiformes) represent a homogenous group, although it is just possible that the Soleidae and Cynoglossidae may have arisen from another part of the percoid stem”; and that “if the flatfishes have derived from a percoid stock, then Psettodes provides just that intermediate stage which might be expected”. – His conclusions say it all. Based on otolith studies there is absolutely no argument against this view. Otoliths of the Psettodidae, Citharidae, Brachypleuridae, Scophthalmidae, Bothidae and Pleuronectidae can all be linked in a convincing morphological-evolutionary succession as has already been pointed out by FROST (1930). Otoliths of the Soleidae and Cynoglossidae indeed seem to be somewhat separated from the rest of the Pleuronectiformes, but in principal their morphology is still in good accordance with that of the other families of the order. 5.3 Pleuronectiform “grouping” according to their otolith morphology 5.3.1 Evolutionary trends in pleuronectiform otolith morphologies The otoliths of the Pleuronectiformes as a group are characterised by a certain tendency towards reduction or “simplification” of the morphological pattern (although certain “specialised” patterns are to be found as well). This trend is likely to reflect some kind of functional morphological adaptation similar to those observed in other benthic fishes (see also chapter 6.1). What exactly has caused this development remains unknown at present. Schwarzhans: Pleuronectiformes 29 When comparing otoliths of the most primitive groups (Psettodidae, Citharidae, Tephrinectes, Paralichthodes, Ammotretis Group) with that of “intermediate” forms (Scophthalmidae, Brachypleuridae, Achirinae and certain genera of the Bothidae and Pleuronectidae) and finally the most derived forms (many Bothidae and Pleuronectidae, Soleinae, Pardachirinae and Cynoglossidae) a number of morphological “simplification trends” become apparent. They are the following: – Reduction of the inclination of the caudal tip to form a straight cauda; – Reduction of the ostial opening; – A change of sulcus proportions so that the cauda, which is originally longer than the ostium, first reaches the same length as the ostium and finally becomes considerably shorter; – An adjustment of ostial and caudal width; – A tendency towards the fusion of the ostial and the caudal colliculi. These “simplification” trends apparently have occurred parallel and independently in several pleuronectiform lineages, again suggesting their adaptive functional morphological nature. In contrast to this development there are only few “specialisation trends”: – The continuous development of the circumsulcal depression; – Special sulcus morphologies observed in the Syacium and Citharichthys Groups (of Bothidae) and the Cynoglossidae (see chapter 6.1 for explanation). In many instances this morphological development reflects, in my opinion, true evolution (see next chapter and entries for specific Groups for more details). A particularly well documented example is the following supposedly phylogenetic succession starting with the Psettodidae: – Psettodidae – Tephrinectes (and possibly also Paralichthodes) – Citharidae – Scophthalmidae – Bothidae (Paralichthyinae). 5.3.2 Definition of suborders, families and genus groups according to otolith morphologies (Fig. 1) Ichthyological studies of flatfishes have almost exclusively been based on meristic, morphometric and osteological analyses of the fishes themPiscium Catalogus, Part Otolithi piscium, Vol. 2 selves. To the best of my knowledge NORMAN (1934) has been the only one to consider otoliths at all. Since the present study of pleuronectiform otoliths represents the first comprehensive one of its kind it is only natural that one of its tasks is to test the traditional ichthyological classification of the group by incorporating the results of otolith analyses. However, since the Teleostei have become a prime play ground for cladistic analyses the understanding of pleuronectiform interrelationships and definition of families (and subfamilies) has undergone a number of changes in recent years (LAUDER & LIEM 1983, HENSLEY & AHLSTROM 1984 and CHAPLEAU 1993). These and other published analyses are taken into consideration and are discussed in the introductionary chapters to the larger systematic units and are summarised in the following chapter (5.4). The grouping of the Pleuronectiformes presented in this treatise is principally based on otolith morphology. Wherever possible, I have used available family names to which I have assigned my otolith groups (genus groups). The only exceptions are the Brachypleuridae, formerly regarded as a subfamily of the Citharidae and here understood as a separate family, and the genera Tephrinectes, Paralichthodes and those of the Ammotretis Group. The latter are removed from their position in the Bothidae and Pleuronectidae respectively and are placed in a category of uncertain family affinities. The three generic groups in question may not be related to each other. According to otolith morphology, however, they exhibit a decisively plesiomorphic pattern that indicates an early phylogenetic separation from the main evolutionary branches of the Pleuronectoidei (i.e. Bothidae and Pleuronectidae). The various and changing concepts of subfamilies (or separated families) in the Bothidae, Pleuronectidae and Soleidae are being used in an informal way only and in essence are replaced by “genus groups” based on otolith morphology. I feel that the loose assignment in genus groups more accurately reflects the taxonomic information that can be gained from otoliths. The genus groups as defined below usually represent smaller units than the subfamilies in use. The intention has been to break down the vast number of genera to form clusters which based on otolith analysis look similar and may in fact represent homogenous groups. The interrelationship of the various genus groups on the other hand is much less well defined. However, in most instances they can be 30 PSETTODIDAE Fam. indet. Psettodes Tephrinectes Fam. indet. CITHARIDAE Ammotretis Citharus Fam. indet. Paralichthodes BRACHYPLEURIDAE Brachypleura SCOPHTHALMIDAE Scophthalmus Lepidorhombus Zeugopterus Paralichthys BOTHIDAE Pseudorhombus Bothus Syacium Arnoglossus Thysanopsetta Monolene-Laeops Chascanopsetta Citharichthys Engyprosopon Mancopsetta Schwarzhans: Pleuronectiformes 31 PLEURONECTIDAE Hippoglossus Hippoglossoides Pleuronectes-Limanda Isopsetta Microstomus-Pleuronichthys Pelotretis Glyptocephalus Samaris Rhombosolea Verasper Marleyella Achirus Poecilopsetta Apionichthys SOLEIDAE Solea Synaptura Brachirus Zebrias CYNOGLOSSIDAE Pardachirus Heteromycteris Cynoglossus Fig. 1: Pleuronectiform otoliths – quick look interpretation chart. (Generic names below figures refer to otolith groups.) Piscium Catalogus, Part Otolithi piscium, Vol. 2 Symphurus 32 grouped conveniently in existing subfamilies (or “super”-groups). In the light of the rapidly changing classification concepts in Pleuronectiformes as a result of the various recent phylogenetic and cladistic studies I have adhered to the more conservative view of pleuronectiform family grouping of NELSON (1984). Other findings forwarded in HENSLEY & AHLSTROM (1984), CHAPLEAU (1993) and their adoption in NELSON (1994) are nevertheless discussed and compared with otolith-based groupings (see chapter 5.4). I must stress the point that the otolith genus groups introduced here have the character of a “working hypothesis” aimed to give some help Classification combined from NORMAN (1934), CHABANAUD (1939) and NELSON (1984) Psettodoidei Psettodidae Pleuronectoidei – (ex Bothidae) (ex Pleuronectidae) (ex Pleuronectidae) when arranging all the diverse otolith morphologies in this order. The work is certainly not intended to introduce a new “official” subclassification of the families of the order Pleuronectiformes in the sense of subfamilies or tribes. The following table gives a guide of how the otolith genus groups described (third row) fit into the traditional classification of the Pleuronectiformes (first row, composed from NORMAN 1934, CHABANAUD 1939 and NELSON 1984) and the more recent classification based on cladistic analyses (second row, adopted from NELSON 1994 after HENSLEY & AHLSTROM 1984 and CHAPLEAU 1993). combined from HENSLEY & AHLSTROM (1984) Otolith grouping CHAPLEAU (1993) as proposed in this paper and NELSON (1994) Psettodidae Psettodidae – (ex Paralichthyidae) (ex Pleuronectidae) (ex Pleuronectidae) genera of uncertain relationship: Tephrinectes Group Paralichthodes Group Ammotretis Group Citharidae Citharinae Brachypleurinae Citharidae Scophthalmidae Scophthalmidae Scophthalmidae Scophthalmus Group Lepidorhombus Group Zeugopterus Group Bothidae Paralichthyinae (excluded: Tephrinectes, Thysanopsetta, Monolene, Engyophrys, Trichopsetta) Paralichthyidae – (excluded: Tephrinectes, Thysanopsetta) Bothinae Bothidae Bothidae Paralichthys Group Pseudorhombus Group Citharichthys Group Syacium Group (fam. indet.) Tephrinectes Group Bothus Group Arnoglossus Group Monolene-Laeops Group Engyprosopon Group Thysanopsetta Group Chascanopsetta Group Mancopsetta Group – – Achiropsettidae Pleuronectidae Pleuronectinae Pleuronectidae Pleuronectinae Citharidae Brachypleuridae Pleuronectidae Hippoglossus Group Hippoglossoides Group Schwarzhans: Pleuronectiformes 33 Poecilopsettinae Paralichthodinae Samarinae Poecilopsettinae Paralichthodinae Samaridae Rhombosoleinae Soleoidei Soleidae Achirinae Apionichthyinae Soleinae Rhombosoleinae Achiridae Soleidae Achirus Group Apionichthys Group Solea Group Synaptura Group Brachirus Group Zebrias Group Pardachirus Group Heteromycteris Group (incl. Peltorhamphus ex Pleuronect.) Soleidae Pardachirinae Heteromycterinae Cynoglossidae Cynoglossinae Symphurinae Cynoglossidae Cynoglossinae Symphurinae The traditional classification of the Pleuronectiformes is based on several characters, the most widely used ones being the position of the optic nerve of the migrating eye and the side on which the eyes are located. In the Psettodoidei and Soleoidei the optic nerves are crossed, which is thought to be a plesiomorphic character, whereas in the Pleuronectoidei the optic nerve of the migrating eye is always dorsal. In the Psettodidae (and Tephrinectes too) the eyes can be sinistral or dextral. The Citharidae were defined by the position of the anus on the eyed side and the presence of 1 spine in the pelvic fins. In the subfamily Citharinae the eyes are sinistral, whereas in the Brachypleurinae they are dextral. Scophthalmidae and Bothidae have sinistral eyes, Pleuronectidae dextral eyes. The Scophthalmidae are characterised by the elongate pelvic fin base. The two bothid subfamilies Paralichthyinae and Bothinae Piscium Catalogus, Part Otolithi piscium, Vol. 2 Glyptocephalus Group Pleuronectes-Limanda Group Isopsetta Group Verasper Group Microstomus-Pleuronichthys Gr. Marleyella Group Poecilopsetta Group (fam. indet.) Paralichthodes Group Samaris Group (incl. Azygopus ex Rhombosoleinae) Pelotretis Group Rhombosolea Group excluded genera: (fam. indet.) Ammotretis Group (Soleidae) Peltorhamphus (Samarinae) Azygopus Cynoglossidae Cynoglossus Group Symphurus Group are defined by the presence or absence of branched pectoral and pelvic rays and symmetry or asymmetry of pelvic fin bases. In the suborder Soleoidei again the two families are distinguished by the position of the eyes:- in Soleidae eyes are dextral, in Cynoglossidae eyes are sinistral. In the following paragraphs I have briefly summarised the otolith characters used to distinguish the families and the otolith genus groups. For more detailed discussions see respective entries to families and genus groups. Psettodid otoliths are defined by a combination of very plesiomorphic characters (see description in chapter 5.2). The genera Tephrinectes (ex Bothidae), Paralichthodes (ex Pleuronectidae) and those of the Ammotretis Group (ex Pleuronectidae) exhibit a similarly plesiomorphic otolith pattern. This is also the reason, why they are here removed from the fam- 34 ilies in which they have traditionally been placed and put in a category of uncertain relationship in an open familial status. They may in fact not be closely related, representing various early evolutionary “spin-offs” from the main pleuronectoid branches. Tephrinectes differs from Psettodes solely in the ostium to cauda ratio, which is nearly 1. In Psettodes and Paralichthodes the cauda is considerably longer than the ostium. Paralichthodes otoliths are remarkable for their extremely faint ventral portion of the circumsulcal depression and the rather strong inclination of the caudal tip, the strongest of its kind found in the Pleuronectiformes. Otoliths from the Ammotretis Group are quite different from those of any other pleuronectiforms. They show a clear sulcus opening, a cauda that is narrower than the ostium and about equal in length, sometimes with a peculiar pointed tip, and a very faint and incomplete circumsulcal depression. This pattern must be regarded as decisively plesiomorphic despite the apomorphic appearance of the fishes themselves. If found isolated and without knowledge of the recent fish from which they were dissected one would hardly recognise otoliths of the Ammotretis Group as belonging to the Pleuronectiforms. In conclusion, I would suggest from otolith analysis that the Ammotretis Group is of pre-pleuronectid origin and should be separated from the Pleuronectidae and put in a family of its own. In the Citharidae ostium and cauda are of about the same length, but the cauda is much narrower than the ostium. Morphologically, these otoliths occupy an intermediate stage between the very plesiomorphic otoliths of the Psettodidae and the more specialised ones of the “higher Pleuronectoidei”, which is in accordance with the position this family occupies in the cladogram of LAUDER & LIEM (1984) (see chapter 5.4). Brachypleurid otoliths differ from citharids in the short cauda with its rounded tip, equally in width with the ostium and the anteriorly reduced sulcus opening, which are all apomorphic features. The genus Brachypleura is more advanced than Lepidoblepharon in many aspects of the otolith morphology. The rostrum is strongly reduced. A unique feature is also the slight ventral expansion of the collum (see chapter 6.1. for explanation; incipiently so in Lepidoblepharon). In outline, the compressed Brachypleura otoliths with their strong predorsal lobe resemble those of certain Soleidae. Lepidoblepharon otoliths in outline resemble more citharid otoliths. This, however, is re- garded as a plesiomorphic feature indicating basal relationship of the two families. Scophthalmid otolith morphologies are quite divergent. That of the Scophthalmus Group resemble psettodids or citharids but with a cauda much more reduced in length. Lepidorhombus appears to fit perfectly within the Bothidae and is remarkable for its extreme side dimorphism in otoliths. Otoliths of the Zeugopterus Group look like “dwarfed” Scophthalmus otoliths, but with a cauda less reduced in length. The ostial opening in all Scophthalmidae is either present or only very slightly reduced. Bothid otoliths display a wide variety of patterns. Recognition of bothid otoliths depends on correlation with and assignment to a certain otolith genus group. In general terms, however, two major morphological groupings are readily distinguishable, to which subfamily ranking is here applied: 1. One group with relatively thin, large and mostly flat otoliths with a moderately to strongly reduced sulcus opening. This “supergroup” roughly corresponds to NORMAN’s Paralichthyinae, but much better to HENSLEY & AHLSTROM’s Paralichthyidae. Within this “supergroup” there is one particularly well established morphological-evolutionary trend starting with Paralichthys and Lioglossina leading to the Pseudorhombus Group and then to the Citharichthys and Syacium Groups. This trend is characterised by the development of the “fusiform” sulcus outline (see chapter 6.1). 2. The second “supergroup” comprises smaller more compact and robust otoliths, often with a deep sulcus and with a clear ostial or at least pseudoostial sulcus opening. This “supergroup” more or less corresponds to NORMAN’s Bothinae, or the Bothidae of HENSLEY & AHLSTROM (1984) together with the Achiropsettidae of HENSLEY (1986). – The position of the Thysanopsetta, Chascanopsetta and Mancopsetta Groups remains somewhat obscure (here included in the Bothinae for convenience). In pleuronectids as in bothids there is not a single otolith character that could unambiguously be used for definition. – However, the various genus groups combined in the Pleuronectinae are characterised by a more or less strongly reduced sulcus opening (except for the Verasper and Microstomus-PleuSchwarzhans: Pleuronectiformes 35 – – – ronichthys Groups, which have a clear sulcus opening), a short cauda, a relatively smooth inner face and a rather thin appearance. Otoliths of the Samaris Group (Samarinae) are characterised by an extremely deep sulcus and an extremely deep circumsulcal depression. The ostium shows a distinct opening often with a clear cut excisura. The genus Azygopus, which was placed by (NORMAN 1934) in the Rhombosoleinae is tentatively included in this group as well. Otoliths of the Poecilopsettinae contain two morphologies. That of the Marleyella Group is rather plesiomorphic resembling citharids in many aspects except that cauda and ostium are of about equal width. In the Poecilopsetta Group the sulcus morphology is more reduced, particularly the length of the cauda. These otoliths are robust, round in shape, with an ostial to pseudoostial sulcus opening. The otolith morphology of Marleyella suggests that the Poecilopsettinae represent a basal offshot from the Pleuronectidae or from the Brachypleuridae (Lepidoblepharon). Rhombosoleinae, as defined by NORMAN (1934), seem to me to represent a catch-all assemblage of dextral Pleuronectoidei from the Southern Oceans. I have considerable doubts that this subfamily really represents a homogenous unit. NORMAN pointed out that some rhombosolein genera resemble Soleidae, but argued that this would be due to convergence. On this point I agree with his conclusions except for the genus Peltorhamphus which shows a typical soleid sulcus pattern (and therefore is here placed in the Soleidae). Also the genera that I have put together in the Ammotretis Group are here removed from the Pleuronectidae and placed in a category of uncertain familial relationship (see above). Pelotretis shows rather indistinct otoliths similar to so many pleuronectids, but also to Lepidorhombus of the Scopthalmidae. Rhombosolea has rather unique otoliths with a strongly outwardly curved ventral margin and the mirror image orientation of the asymmetric characters (see chapter 6.2). Otherwise it might be considered a pleuronectid. Otoliths of Azygopus, with their very deep sulcus and deep excisura, are quite different from other Rhombosoleinae. This genus is here included in the Samaris Group. In certain general aspects they resemble those of the Ammotretis Group which Piscium Catalogus, Part Otolithi piscium, Vol. 2 I have removed from the Pleuronectidae altogether. To me the relationship of several socalled rhombosolein genera, as mentioned above, remains obscure. Only Pelotretis and Rhombosolea in my classification remain in the subfamily Rhombosoleinae. Otoliths of the Soleidae are in my opinion recognised quite easily, although it is difficult to say which characters precisely make them look so peculiar. They are compressed otoliths with a rather regular round or oval shape, a somewhat reduced sulcus opening and a tendency towards a shallow sulcus and fused or at least poorly defined colliculi. Often, their inner face is quite convex and smooth which can best be shown in lateral views. – The Achirus Group corresponds to the subfamily Achirinae and probably represents the most plesiomorphic sulcus pattern found in the Soleoidei. Ostium and cauda are of about equal length or the cauda is just slightly shorter than the ostium. The sulcus is slightly deepened to considerably deepened in some genera (Gymnachirus and Nodogymnus) which show also fused colliculi. In this respect otoliths of the Zebrias Group, traditionally placed in the Soleinae, are quite similar to those of the genus Gymnachirus. Whether this resemblance reflects true relationship of the two groups or just convergent evolution remains to be tested by other characters. However, due to the resemblance of otoliths of the genera of the Zebrias Group to those of the Brachirus Group I have elected to keep them in their traditional place. – Otoliths of the Apionichthys Group (Apionichthyinae in CHABANAUD, 1939), although not very well known, do not seem to depart much from the pattern found in the Achirus Group and are here included in the Achirinae. – The Soleinae include quite a variety of otolith morphologies. Otoliths of the Synaptura Group are elongate and exhibit a very special sulcus morphology different from all other Soleoidei. The cauda is short, but the ostium is bipartite with its anterior portion considerably narrowed. Otoliths of the Solea Group exhibit the typical soleid otolith pattern. The outline of the otoliths is evenly rounded. The inner face is convex (except for Bathysolea and Vanstraelenia which have flat inner faces). The cauda is small, usually shorter than the ostium. The sulcus is not much deepened and 36 there is a notable tendency for a fusion of the colliculi. Otoliths of the Brachirus Group are similar in general appearance, but with a rather flat inner face and an anteriorly narrowed outline. The genera of the Zebrias Group are thought to have derived from the Brachirus Group and are characterised by flat and thin otoliths with a rather short and deep sulcus and fused colliculi, thus resembling certain genera of the Achirus Group (see above). Where not completely fused, colliculi are about equal in length, which is the main distinction from otoliths of the Brachirus Group (together with the anteriorly reduced ostium). – The otoliths of the Pardachirus Group (Pardachirinae in CHABANAUD, 1939) and the Heteromycteris Group (Heteromycterinae in CHABANAUD, 1939, but including the genus Peltorhamphus ex Pleuronectidae, subfamily Rhombosoleinae, sensu NORMAN, 1934) all look very similar. Based on otolith morphology alone they could easily be combined in a single group or subfamily, the Pardachirinae. The characters defining this group are a compressed outline with a deeply curved posteriorly oriented ventral rim and a rather flat dorsal rim, a strongly convex inner face which is rather smooth including a shallow sulcus, a concave outer face, the circumsulcal depression often being reduced in width and a short almost circular cauda which in some genera exhibits a tendency to widen. The development of the circumsulcal depression is the only character useful for distinguishing the members of the two genus groups: in the Heteromycteris Group it is moderately narrowed and usually runs close to the sulcus, and in the Pardachirus Group it is most narrowed, almost to a furrow that runs close to the rims of the otolith. Cynoglossid otoliths are in many respects very similar to those of this “supergroup” (the Pardachirinae) and in fact may very well have originated from it. The peculiar widened cauda of the Cynoglossidae seems to be “foreshadowed” in certain genera of this “supergroup”, such as Pardachirus and even more so in Rendahlia (Heteromycteris Group). Cynoglossid otoliths are readily recognised by their “hammer-shaped” sulcus (see chapter 6.1) which has resulted from a distinctive widening of the cauda. Ostial and caudal colliculum are fused. In all other aspects otoliths of the Cynoglos- sidae perfectly resemble those of the Pardachirus and Heteromycteris Groups of the Soleidae from where in fact they may have originated. Otoliths of the Cynoglossus Group exhibit the more plesiomorphic pattern, whereas those of the Symphurus Group are characterised by a further specialisation of the sulcus outline and the circumsulcal depression. The two groups have traditionally been placed in two separate cynoglossid subfamilies, but I have refrained from doing so due to the close relationship of the two groups. Typical representatives of each of the otolith genus groups as defined in this treatise are schematically outlined in a quick look interpretation chart (fig. 1). 5.4 Discussion of phylogenetic concepts in Pleuronectiformes (Fig.2-4) Until recently, NORMAN’s classification with modifications by HUBBS (1945), AMAOKA (1969), FUTCH (1977) and HENSLEY (1977) represented the most detailed hypothesis for pleuronectiform evolution. This model is depicted in row one of the classification list in chapter 5.3.2 and as a phylogram in figure 2. It has served as basis for the otolith analysis of Pleuronectiformes as presented here. However, as HENSLEY & AHLSTROM (1984) stated: “Formation of the (Regan-)Norman model involved an eclectic approach, i.e. a combination of phyletic and phenetic methods. Although some of the groups (currently) recognised appear to be based on synapomorphies, many are clearly based on symplesiomorphies and were recognised as such by the authors.” In recent years a number of publications have been published devoted to a more cladistic phylogenetic interpretation of pleuronectiform relationships (or certain pleuronectiform families). These are works by LAUDER & LIEM (1983), HENSLEY & AHLSTROM (1984), SAKAMOTO (1984) and CHAPLEAU (1987,1993). The results of these analyses are briefly discussed in the following and are compared to the findings of analyses of the otolith morphology. A first cladistic analysis of the Pleuronectiformes was presented by LAUDER & LIEM (1983). In their cladogram the Psettodidae are identified as the plesiomorphic sister-group of Schwarzhans: Pleuronectiformes 37 Fig. 2: Hypothesis of interrelationships of pleuronectiform fishes presented in HENSLEY & AHLSTROM (1984), based on NORMAN (1934), HUBBS (1945) and AMAOKA (1969) all remaining Pleuronectiformes. The next dichotomy separates the Citharidae (loss of spines in dorsal and anal fins, loss of dentition on palatinum and basihyale, tip of dorsal fin commencing above eye). They are characterised by one supposedly autapomorphic character – the shift of the anus onto the eyed side. In the case of the Brachypleuridae (usually accorded subfamily rank within the Citharidae) the synapomorphic nature of this character must be doubted. Presence of a spine in the pelvic fin separates the Citharidae (sensu HUBBS 1945, LAUDER & LIEM 1983) from the Scophthalmidae, which are separated next from the main branch of the Pleuronectiformes. Loss of dentition on the vomer and uniting of the branchiostegal membranes of the two sides characterises the remaining “higher” Pleuronectiformes from which Pleuronectidae and Bothidae are subsequently separated as the next units. Finally, Soleoidei are regarded as the most advanced pleuronectiforms characterised by the loss of the postcleithra and the ribs. And within the Soleoidei, Cynoglossidae are the last group to be singled out on the basis of the loss of the pectorals (which, however, are also missing Piscium Catalogus, Part Otolithi piscium, Vol. 2 in some Soleidae). – In the Psettodoidei and Pleuronectoidei this phylogenetic interpretation largely reflects NORMAN’s concept of classification (1934) including HUBBS’ (1945) emendations. Soleoidei, however, were then thought to represent a separate lineage from Pleuronectoidei altogether. Fossil evidence both from skeletons and otoliths extends back well into Eocene times (see respective entries) and thus support the concept of an early evolutionary separation of the Soleoidei, earlier in fact than is suggested by LAUDER & LIEM’s cladogram. Since then further and more detailed cladistic analyses have been published by HENSLEY & AHLSTROM (1984) and CHAPLEAU (1993) plus a specialised one dealing exclusively with interrelationships of the family Pleuronectidae by SAKAMOTO (1984) (see also NELSON 1994). HENSLEY & AHLSTROM and CHAPLEAU questioned the monophyly of the families Citharidae and Pleuronectidae. For Citharidae CHAPLEAU suggested that the dextral Lepidoblepharon and the sinistral Citharoides form a trichotomy with all remaining Pleuronectiformes, including the other citharid genera (the sinistral Citharus 38 Fig. 3: Hypothesis of interrelationships of pleuronectiform fishes redrawn from the consensus tree diagram presented by CHAPLEAU (1992). and the dextral Brachypleura). Otoliths, however, strongly indicate that the separation of the former Citharidae runs between the sinistral and the dextral genera, and in fact they are here placed in two separate families – Citharidae and Brachypleuridae. Nevertheless, in this concept Lepidoblepharon represents the more plesiomorphic character status within the Brachypleuridae, resembling Citharidae in several plesiomorphic aspects, such as the outline of the otoliths. HENSLEY & AHLSTROM regard Brachypleura as related to the Scophthalmidae-Bothidae lineage because of the hypural pattern which it shares with those but not with the Citharidae (sensu strictu). From the otoliths point of view, I feel unable to define which of the two families (Citharidae and Brachypleuridae) may in fact be more closely related to the higher Pleuronectoidei (Scophthalmidae, Bothidae and Pleuronectidae). They do most likely represent a basal alignment from near which these families may have evolved. HENSLEY & AHLSTROM (and also CHAPLEAU) separated the Bothidae in the two families Bothidae and Paralichthyidae. This separation is adopted here as well, but with subfamily ranking. Based on the analysis of the pattern of the hypurals HENSLEY & AHLSTROM defined one particular pattern they referred to as the ‘bothoid group’, containing Brachypleura, Scophthalmidae, most Bothidae (in the sense used here) and Pleuronectinae. HENSLEY & AHLSTROM excluded Tephrinectes and Thysanopsetta from their bothoid group stating that “these two genera are much more primitive than expressed in the current classification and definitely do not belong to the bothoid group”. Also, they support the removal of the genera Taeniopsetta, Monolene, Engyophrys and Trichopsetta from the Paralichthyidae (here Paralichthyinae) to the Bothidae (here Bothinae). Within the Paralichthyidae they distinguish three groups – a plesiomorphic, possibly non-monophyletic group containing the genera Ancylopsetta, Gastropsetta, Hippoglossina, Lioglossina, Paralichthys and Xystreurys and two better defined apomorphic groups, the Cyclopsetta group with Cyclopsetta, Syacium, Citharichthys and Etropus and the Pseudorhombus group with Pseudorhombus, Tarphops and Cephalopsetta. These conclusions are in perfect agreement with the otolith findings (see entries to the Tephrinectes Group and the Bothidae and its groups). Schwarzhans: Pleuronectiformes 39 Fig. 4: Hypothesis of interrelationships of pleuronectiform fishes according to otolith analysis as proposed in this treatise. – Characters used for discrimination are: Inherited plesiomorphic characters: A = Dorsal depression; B = Ostial sulcus opening; C = Ostium shorter and wider than cauda; D = Cauda curved; Apomorphic characters: 1 = Ventral depression; 2 = Cauda about equal in length to ostium; 2a = Caudal tip widened; 2b = Caudal tip pointed; 2c = Cauda shorter than ostium; 3 = Sulcus opening pseudoostial; 3a = Sulcus closed; 3b = Secondary sulcus opening; 4 = Cauda straight; 5 = Loss of tapering caudal tip; 6 = Circumsulcal depression complete; 7 = High, “soleiform” outline of otolith; 8 = Collum ventrally widened; 9 = Circumsulcal depression narrow; 10 = Hammer shaped sulcus; 11 = Colliculi fused; 11a = Colliculi partly fused. Hatched markers indicate that only some genera of the group have developed the respective character. Note: Some of the reduced characters (such as 4, 5, 11) apparently have occured in independent lineages. Within the Bothidae (sensu HENSLEY & AHLSTROM, here Bothinae) two groups or subfamilies are recognised by HENSLEY & AHLSTROM – the plesiomorphic Taeniopsettinae including at least Taeniopsetta, Engyophrys, Trichopsetta and Perissias and (poorly defined) the Bothinae for the remainder. Otolith analysis is less conclusive in this group. The genus Mancopsetta is not regarded as a bothoid by HENSLEY & AHLSTROM because of several primitive characters not found in the Bothidae. EVSEENKO (1984) later erected a family Achiropsettidae (here equivalent to the Mancopsetta Group). Both HENSLEY & AHLSTROM and CHAPLEAU regard the Pleuronectidae as non-monophyletic, with the Pleuronectinae being more Piscium Catalogus, Part Otolithi piscium, Vol. 2 closely related to the Paralichthyidae (ex Bothidae). According to HENSLEY & AHLSTROM the Pleuronectinae are the only pleuronectid subfamily with a bothoid hypural pattern, thus relating them to the Bothidae (in the sense used here) and demonstrating the polyphyly of the Pleuronectidae. Likewise, CHAPLEAU identifies the Pleuronectinae as the most plesiomorphic subfamily in Pleuronectidae and close to the Bothidae (s.l.). Pleuronectine otoliths too show a close resemblance to those of the bothid subfamily Paralichtyinae and differ considerably from those of the other pleuronectid subfamilies. HENSLEY & AHLSTROM concluded that the other pleuronectid subfamilies do not show the bothoid hypural pattern and used this observation as an argument for the supposed polyphyly 40 of the Pleuronectidae. CHAPLEAU recommended that the Poecilopsettinae, Rhombosoleinae and Samarinae be raised to familial rank. Seeing the uncertainties for instance in the interrelationships of the so called Rhombosoleinae (see entry to Rhombosolea Group and Pleuronectidae) I agree with NELSON (1994) that this classification is at this stage premature, but the principal concept of the Pleuronectidae being possibly polyphyletic is supported by otolith analyses. The Poecilopsettinae are placed in CHAPLEAU’s cladogram near to the Rhombosoleinae, whereas SAKAMOTO combines them in the Pleuronectinae-Poecilopsettinae stem. The Samarinae show a number of highly specialised features both in skeleton and in otoliths. Their interrelationships therefore presently are much under debate. Both HENSLEY & AHLSTROM and CHAPLEAU find arguments that they could be related to soleoids. However, otolith analysis strongly contradicts this view. The degree and kind of otolith specialisation found in Samarinae has nothing in common with that observed in the Soleoidei. Furthermore, fossil evidence seems to indicate that the Soleoidei are a rather ancient group in pleuronectiforms and may have split off from the other pleuronectiform stems much earlier than is suggested by modern cladograms (see fig. 3, cladogram from CHAPLEAU 1993). Paralichthodes has usually been associated with the Samarinae either as a separate but related subfamily or entirely included with the Samarinae. Its otolith pattern is distinctly plesiomorphic pointing to a pre-bothid/pleuronectid origin (see entry to Paralichthodes Group), but this conclusion will need further verification by other ichthyological investigations. Finally, the Rhombosoleinae represent the most enigmatic subfamily within the Pleuronectidae. Except for SAKAMOTO (1984) they have not been subject to a recent review and a phylogenetic analysis. In SAKAMOTO’s cladogram of the Pleuronectidae the various rhombosoleine genera are widely separated although he still regards them as a distinct unit. Otolith analysis instead clearly demonstrates the Rhombosoleinae not to represent a natural assemblage (see chapter 5.3.2. and entries to Ammotretis, Samaris, Pelotretis and Rhombosolea Groups and Soleidae). Part of the so-called Rhombosoleinae are probably of pre-bothid/pleuronectid origin or are related to the Samarinae (Ammotretis Group and Azygopus) and one genus (Peltorhamphus) is removed to the Soleidae. As understood here, only Pelotretis and Rhombosolea remain in the Rhombosoleinae sensu strictu. Soleoidei have been thought to form a monophyletic group in recent cladistic analyses (HENSLEY & AHLSTROM, 1984 and CHAPLEAU, 1988). Achiridae are separated from Soleidae and are thought to represent the primitive sister group to Soleidae and Cynoglossidae, according to CHAPLEAU (1993). HENSLEY & AHLSTROM note that the Achirinae exhibit a very primitive hypural pattern and thus assume that the Soleoidei might be of rather early origin. This view is support by the geologically early findings of soleoid otoliths. In contrast LAUDER & LIEM (1983) and CHAPLEAU (1993) have separated the Soleoidei as the latest stem from the pleuronectiform cladogram, branching even later than the Pleuronectidae and close to the Samarinae. Also the separation of Achirinae and Soleinae is supported by otolith analysis (I have left them at subfamily rank next to Soleinae and Pardachirinae). All authors regard the Cynoglossidae as being closely related to the Soleidae. CHAPLEAU (1993) in his cladogram separates the Achiridae (here Achirinae) first before the dichotomy of Soleidae and Cynoglossidae. Otoliths indeed strongly support the concept of the Cynoglossidae having derived from the Soleidae. From otoliths there is convincing synapomorphic evidence that the Cynoglossidae originated from near Pardachirinae of the Soleidae (see respective entries). CHAPLEAU (1988) analysed the interrelationships of the Cynoglossidae concluding the Symphurinae (here Symphurus Group) to represent the plesiomorphic sister group of the Cynoglossinae (here Cynoglossus Group). Otolith analysis, however, contradicts this view. Symphurus otoliths seem to be the more specialised ones. Maybe, the apparent plesiomorphic character of Symphurus fishes represents a secondary reduction rather than a more primitive character state. Conclusions: 1. The basal alignment of the Pleuronectiformes (Psettodidae, Citharidae and Scophthalmidae) accords well with otolith findings. However, CHAPLEAU’s concept of the splitting of the Citharidae is not supported. Instead, it is recommended to separate Citharidae and Brachypleuridae. Also, otolith analysis suggests that Schwarzhans: Pleuronectiformes 41 2. 3. 4. 5. the basal pleuronectiform group may contain additional taxa – the Tephrinectes, Paralichthodes and Ammotretis Groups, here placed in a group of uncertain familial affinities. HENSLEY & AHLSTROM’s concept of subdividing the Bothidae (Paralichthyinae and Bothinae and subgroups including removal of Tephrinectes and perhaps also Thysanopsetta and Mancopsetta) is fully supported by otolith analysis. Otoliths support the hypothesis of the polyphyly of the family Pleuronectidae, with the Pleuronectinae more closely related to the Bothidae than the other subfamilies. The relationships of the other subfamilies remain cryptic. According to otoliths the Rhombosoleinae do not form a natural assembly. In accordance with HENSLEY & AHLSTROM the Soleoidei are thought to represent a natural group of quite early origin. Within the Soleoidei the Achirinae represent the most primitive group and the Cynoglossidae are very likely derived from the Soleidae (Pardachirinae). For comparison I have figured the three main concepts discussed as cladograms or phyllograms. Fig. 2 shows the phylogram according to NORMAN’s model (from HENSLEY & AHLSTROM, 1984). Fig. 3 shows the cladogram of CHAPLEAU (1993). Fig. 4 depicts the results of the otolith analysis in the form of a cladogram, in order to compare it to the analyses presented by LAUDER & LIEM (1983), HENSLEY & AHLSTROM (1984) and CHAPLEAU (1993) (fig. 2). (Generally, I hesitate to depict assumed “otolith relationships” as cladograms, because I feel that any otolith based systematic suggestions should first be tested and verified by other ichthyological investigations.) 6. Morphological characterisation of Pleuronectiformes otoliths 6.1 Terminology (Fig. 5-13) Pleuronectiform otoliths are not always easily recognised as such. As stated before (see chapters 5.1. and 5.3) there is a widespread tendency within the otoliths of this order towards reduction or “simplification” of certain aspects of their morphology. Sulcus morphology and outline of the otolith are the characters most commonly affected. This morphological “simplification” is thought to be a result of functional morphological adaptation and evidently it has developed independently in several lineages. Although very little is known so far of the functional morphology of otoliths it has been observed empirically that many benthic fishes have developed “look alike” otoliths. Common characteristics are a robust, relatively large otolith, smooth otolith rims and a smooth outer surface and, finally, a “simplified” sulcus pattern. Typically, the sulcus opening is reduced, its outline becomes smoother, ultimately forming a regular oval shape, and ostial and caudal colliculi become fused. Often the sulcus becomes very shallow, level with the rest of the inner face. This kind of sulcus is found in Piscium Catalogus, Part Otolithi piscium, Vol. 2 many pleuronectiforms but is also common in other benthic fishes (for instance Congroidei, Lophiiformes, Ophidiiformes, Gobioidei). There is, however, a second morphotype of sulcus organisation in benthic fishes that is characterised by a deepened (though “simplified”) sulcus usually combined with a well developed opening. Such otoliths are found in the Pleuronectiformes as well, although less commonly, and are also known from such benthic fishes as the Anguilloidei, Gobiesociformes, Cottoidei or Blennioidei. From this discussion it is understandable why pleuronectiform otoliths are not very easily characterised and in the fossil record they have sometimes been confused with representatives of other, unrelated Teleosts. Sulcus morphology, usually the most diagnostically valid and most stable character, in many instances does not allow the differentiation of pleuronectiform otoliths from those of certain other groups of benthic fishes. Fortunately, there is one single character seemingly unique to the Pleuronectiformes. This is the circumsulcal depression. The circumsulcal depression is usually deep and well marked, but there are also instances where it can be relatively feeble (particularly in otoliths from the blind side), 42 very narrow or disrupted behind the tip of the cauda. In these cases proper assignment of isolated otoliths, fossil or recent, to the Pleuronectiformes can become a little more difficult, particularly if erosional effects are also involved. In the following I briefly discuss the various morphological characters that occur in the Pleuronectiformes. For a few peculiar features informal circumscriptive terms are used in order to shorten repeated descriptions in the systematic part. Outline. The outline of most pleuronectiform otoliths is smooth, rounded, but rectangular and other shapes occur as well. Sometimes it is irregularly lobate or undulate. Angles along the rims are rare, the most common ones being an obtuse medioventral angle particularly in the Psettodidae (fig. 6), Scophthalmidae and certain Bothidae (fig. 9). A postdorsal angle situated at the very end of the dorsal rim is characteristic for several pleuronectids and can be quite sharp (fig. 10). Otherwise pre- and postdorsal angles are rarely observed and are usually very feeble. Certain Soleidae and Cynoglossidae have developed some kind of predorsal lobe at the anterior end of the dorsal rim. This predorsal lobe is also present in Brachypleura and in fact has been developed most strongly (fig. 11). In some Bothidae (Pseudorhombus, Syacium and Citharichthys Groups) the predorsal rim is expanded to some kind of broad projection. The posterior tip of the otolith can be developed quite diversely. Usually it is blunt or rounded, but it can also be pointed. Pointed posterior tips are known from the Psettodidae (fig. 6; inframedian), some Citharidae, Bothidae (fig. 9) and the pleuronectid genus Marleyella (median) and Paralichthodes (supramedian). Concave posterior rims occur in most Cynoglossidae and the Solea and Pardachirus Groups of the Soleidae (fig. 12). Anteriorly many pleuronectiform otoliths exhibit some kind of rostrum (fig. 6-11), whereas development of an excisura (see sulcus opening) and an antirostrum are much more seldom (fig. 7-8). The rostrum is usually massive, not pointed and developed best in the more “primitive” members of the order (fig. 6-9). Nevertheless, a rostrum look-alike and probably homologous projection is also evident from many otoliths with a reduced sulcus opening (fig. 9-11). Development of the rostrum and in some instances its length are important characters of diagnostic value. In certain very thin and delicately ornament- ed otoliths one sometimes observes a tendency to “skeletonization” of the outline of the otolith. This means that radial marginal furrows transform into deep incisions or “fenestrae”. This trend usually occurs in otoliths of epipelagic fishes. In the Pleuronectiformes this phenomenon is observed best in the otoliths of the genus Reinhardtius. In otoliths of the blind side “skeletonization” occurs postdorsally and in otoliths of the eyed side preventrally. Similar effects, although to a much lesser degree, have also been observed in otoliths of the genera Psettodes and Rhombosolea. Inner face. Circumsulcal depression (fig.5a): a depression surrounding the sulcus dorsally and ventrally and joined behind the caudal tip. The circumsulcal depression has developed as a combination of the dorsal depression known from most Teleosts and a ventral depression which in its expression is unique amongst Teleosts. SCHWARZHANS (1995) has postulated that this ventral depression has developed between the area of the “classical” ventral line and a second “doubled” ventral line closer to the sulcus as observed in certain Percoidei. The circumsulcal depression should not be confused with the continuous line (”extended” ventral line) as observed in Gobioidei or the fusion of the ventral line with the dorsal depression seen in certain Trachinoidei. These lines are not homologous and run close to the rim of the otolith. The circumsulcal depression is usually situated very close to the sulcus, leaving only the cristae superior and inferior to separate them. Usually, the separation of the circumsulcal depression is fairly sharp towards the cristae and more gradual outwards towards the otolith margins. An exception is seen in the Cynoglossidae and certain Soleidae which have a (secondarily reduced) narrow circumsulcal depression, sometimes almost reduced to a line, running at some distance from the sulcus (fig. 13). In the genus Symphurus (Cynoglossidae) the circumsulcal depression is bilobate with extended areas postdorsally and postventrally. Width and depth of the circumsulcal depression is quite variable and in some instances can be of diagnostic importance. The junction of the dorsal and ventral depressions behind the caudal tip is usually somewhat shallowed. It is complete in most Bothidae (fig. 9), Pleuronectidae (fig. 8, 10), Soleidae (fig. 12) and Cynoglossidae (fig. 13), but incomplete (disrupted) in the more “primitive” Pleuronectiformes (Psettodidae – fig. 6 -, CithariSchwarzhans: Pleuronectiformes 43 5a 5c 5b 6 7 8 10 9 11 12 13 Fig. 5: Morphological terminology in Pleuronectiform otoliths. Fig. 5a = Inner face; abbreviations: l = length, h = height, s.i.a.=sulcus inclination angle. Figs. 5b, c = View from ventral; abbreviations: t = thickness, con.i. = convexity of inner face, con.o. = convexity of outer face. Figs. 6-13: Morphological examples of Pleuronectiform otoliths – fig. 6 genus Psettodes, fig. 7 genus Bothus, fig. 8 genus Samaris, fig. 9 genus Citharichthys, fig. 10 genus Hippoglosoides, fig. 11 genus Brachypleura, fig. 12genus Solea, fig. 13 genus Cynoglossus (otoliths from the right-eyed flatfishes mirror-furned). Piscium Catalogus, Part Otolithi piscium, Vol. 2 44 dae, Brachypleuridae – fig. 11 – , Scophthalmidae and certain Bothidae – fig. 7). Sulcus. Despite the tendency towards “simplification” of the sulcus morphology observed in so many Pleuronectiformes (see above) the sulcus still remains the single most important character for systematic purposes. However, in many instances the correct interpretation of the outline of the sulcus and the colliculi requires very careful analysis. If the sulcus is very shallow, the outline of the colliculi is usually well defined but the outline of the sulcus may not be. If on the contrary the sulcus is deep its outline is usually sharply developed but the outline of the colliculi may not be. Also the differentiation of the ostial and caudal colliculi is often feeble where they meet or approach each other. Sulcus proportions (fig. 5a): Sulcus proportions include sulcus versus whole otolith correlations (otolith length to sulcus length; approach of caudal tip to posterior tip of otolith; in the case of an anteriorly closed sulcus approach of the ostial tip to the anterior tip of the otolith). Intrasulcus correlations are more important, in particularly the length of the ostial colliculum to the length of the caudal colliculum (ol:cl). In most pleuronectiform otoliths the ostium is longer than the cauda, often by a factor of two or more. However, in the more “primitive” members of the order (Psettodidae, Paralichthodes, Tephrinectes, Ammotretis Group, Citharidae and some Achirinae) they are of about equal length or the cauda is actually longer than the ostium (fig. 6). It appears that reduction of the cauda has developed at a faster pace than reduction of the ostium. Within the Soleidae, however, there is a single genus (Quenselia) in which, seemingly, the cauda has become secondarily enlarged, approaching the length of the ostium and, in the case of a fossil species, (Quenselia cornuta), even surpassing it. This secondary enlargement has probably occurred at the expense of the ostial colliculum into which the caudal colliculum appears to be protruding. Other intrasulcus correlations include ostium length to height (ol:oh) and ostium height to cauda height (oh:ch). However, any intrasulcus correlations can of course only be applied where there is a clear distinction between ostium and cauda, i.e. separation of the colliculi. The latter is important since the junction of ostium and cauda is not always marked by an incursion or indentation at the ventral rim of the sulcus. Sulcus opening: A character of some diagnostic value is the status of the sulcus opening. In more “primitive” members of the Pleuronectiformes (Psettodidae, Tephrinectes, Paralichthodes, Ammotretis Group, Citharidae, some Scophthalmidae, Bothidae and the Microstomus-Pleuronichthys and the Samaris Groups of the Pleuronectidae) the ostium distinctly opens anteriorly and the ostial colliculum meets the anterior rim of the otolith (fig. 6-8). A definite ostial excisura is rarely observed (Thysanopsetta, Chascanopsetta, Mancopsetta and some members of the Bothus Group of the Bothidae, Samaris Group – fig. 8 – of the Pleuronectidae). More often one observes a certain reduction of the ostial opening. First it becomes indistinct (pseudoostial opening) with an anteriorly closed ostial colliculum and finally the ostium becomes completely closed anteriorly. The latter has occurred separately in several distinct lineages, for instance in the Brachypleuridae (fig. 11), the Citharichthys (fig. 9) and Syacium Groups of the Bothidae, the Isopsetta, PleuronectesLimanda, Hippoglossoides (fig. 10) and Glyptocephalus Groups of the Pleuronectidae, most Soleidae (fig. 12) and Cynoglossidae (fig. 13). Sometimes a faint ostial channel still connects the ostium and the anterior rim of the otolith (fig. 11). Sulcus outlines: Usually, the outline of the sulcus in pleuronectiforms is not very spectacular. Some exceptions, however, are described below. Inclined caudal tip (fig. 6): A faintly inclining caudal tip is only observed in what I regard as the most “primitive” members of the Pleuronectiformes (Psettodidae, Paralichthodes, Tephrinectes, Ammotretis Group and incipiently in some Scophthalmidae). This character is thought to be inherited from some kind of perciform ancestor (see also chapter 5.2). Ventral expansion of collum (fig. 11): A small widening of the sulcus just below the ostial-caudal joint, which is deepened and remains unfilled by colliculi. This character is only known from Brachypleura (and incipiently so from Lepidoblepharon). Bipartite ostium: In otoliths of the Synaptura Group (Soleidae) the long ostium is divided into two portions, marked by collum-like incursions of the rims of the sulcus. The anterior portion of the ostium is much narrower than the strongly widened posterior portion and also deeper. In some instances the bipartition of the ostium can be more distinctly developed than the separation of ostium and cauda. Fusiform sulcus (fig. 9): A very “specialised” Schwarzhans: Pleuronectiformes 45 sulcus outline is characterised by a widening of the sulcus just behind its middle. The anterior and posterior portions are much narrower, the cauda terminating with a pointed tip. Ostial and caudal colliculi are completely fused but it is assumed that the conspicuous widening of the sulcus corresponds with the posterior portion of the ostium. The sulcus is shallow except for the widened portion, which may be somewhat deepened. The fusiform sulcus outline only occurs in the Citharichthys and Syacium Groups and incipiently also in the genus Tarphops of the Pseudorhombus Group (all Bothidae) and is accepted as a synapomorphic character combining these fishes phylogenetically. Hammer-shaped cauda (fig. 13): In the Cynoglossidae and incipiently in a few Soleidae (Pardachirus and Heteromycteris Groups) the cauda is extremely widened, both dorsally and ventrally, but very short. Its posterior termination is abrupt, nearly vertically cut. Together with the much narrower ostium the shape of the sulcus resembles that of a hammer. In the Cynoglossidae the colliculi are fused, but in the Soleidae mentioned above (where this character is only incipiently developed) ostial and caudal colliculi are well separated. This feature, unique amongst Teleostean otoliths, is a perfect autapomorphic character found in all Cynoglossidae. Deep sulcus (fig. 7-8): A continuously deep sulcus is developed in the Ammotretis Group, the Samaris and Microstomus-Pleuronichthys Groups of the Pleuronectidae and part of the Achirus, the Zebrias and part of the Synaptura Group of the Soleidae. That of Samaris is probably the most deeply incised sulcus observed in pleuronectiforms. More commonly, only ostial and caudal colliculi are deepened. They may be connected by a narrow furrow (Zeugopterus Group of Scophthalmidae, certain members of the Bothus and Arnoglossus Groups and the Thysanopsetta, Mancopsetta and Chascanopsetta Groups of the Bothidae) or completely separated, then looking like two holes in the surface of the otolith (Hippoglossoides, Glyptocephalus and Poecilopsetta Groups of the Pleuronectidae). Often the cauda is more depressed than the ostium. Infact, in many soleids the cauda is depressed, whereas the ostium has remained almost completely flat. Sulcus orientation: In most Pleuronectiformes the sulcus occupies a median position on the inner face of the otolith, but supramedian and inframedian positions occasionally occur as well. Piscium Catalogus, Part Otolithi piscium, Vol. 2 In some groups (particularly among the Bothidae) the sulcus is not oriented horizontally on the inner face but inclined downwards (fig. 5a). The angle of inclination measured between the long axis of the otolith and the axis of the sulcus (s.i.a.) is in some instances an important tool for differentiating between related species (for instance of the genus Arnoglossus) or genera. Identification of the horizontal axis of the otolith is not always easy. Rounded otoliths are displayed such that the sulcus runs horizontally. Then, of course, a sulcus inclination angle cannot be measured. Otoliths with anterior and posterior tips are oriented along the axis connecting the two points. Rectangular otoliths (for instance of the Arnoglossus Group) are traditionally figured with their ventral rims running horizontally. In these, the sulcus inclination angle is often an important feature. Curvatures (fig. 5b-c). This is quite commonly another diagnostically important group of features. Curvatures, particularly of the inner face both in horizontal (fig. 5b; con.i.) and in vertical direction can often be used to distinguish the otoliths of related genera which otherwise may look quite similar. Also thickness of the otolith and, to a lesser extent, curvatures of the outer face (fig. 5c; con.o.) are useful characters. Also smoothness of the inner face, depth and width of the circumsulcal depression (as well as of the sulcus) can thus be visualised much better. It is therefore important to figure and describe lateral views of pleuronectiform otoliths, preferably from ventral and anterior aspects. – Outer faces on the other hand do not exhibit much that is of diagnostic value and do not need to be figured in the case of the Pleuronectiformes. Adequate figures from lateral views are sufficient in this respect. 6.2 Side dimorphism (Fig. 14-23) Since pleuronectiform fishes as a group are characterised by their extreme asymmetry similar effects had to be expected from the otoliths. KOKEN (1891), who laid the basis for systematic otolith research, was of the opinion that pleuronectiform otoliths do not exhibit any kind of clear cut asymmetry (apparently he looked at only very few flatfish otoliths). His explanation was that otoliths, situated in the “interior” of the 46 Lepidorhombus whiffiagonis Paralichthys adspersus Trichopsetta ventralis Chacanopsetta lugubris 17 Mancopsetta milfordi 14 15 16 18 Figs. 14-23: Examples of side dimorphism in Pleuronectiform otoliths – fig. 14 family Scophthalmidae, figs. 15-18 family Bothidae, figs. 19-22 family Pleuronectidae, fig. 23 family Soleidae. Schwarzhans: Pleuronectiformes 47 Parophrys vetulus 19 Reinhardtius hippoglossoides 20 Rhombosolea tapirina 21 Glyptocephalus zachirus Piscium Catalogus, Part Otolithi piscium, Vol. 2 22 Dicologlossa cuneata 23 48 fish, may not react as vigorously to the forces of functional adaptation as do organs along the “periphery” of the fishes (for instance dentition). We now know that his assumptions were wrong. CHAINE & DUVERGIER, NOLF and SCHWARZHANS have pointed out in several publications that side dimorphism in the otoliths of the Pleuronectiformes is just as characteristic of the group. However, this phenomenon does not occur in all flatfishes. There are a number of species, genera and families which have relatively symmetrical otoliths or else the asymmetry is so slight that it is indistinguishable as a character, within the normal range of intraspecific variation. Some genera include both species with and without lateral dimorphism. Of course, the phenomenon of asymmetrical otoliths occasionally causes some problems when identifying isolated otoliths particularly in fossils. Although I know of only few instances where left and right hand otoliths have been described as different species (see entry to Laeops splendens from the Miocene of Austria) paleontologists describing fossil flatfish otoliths should be well aware of the phenomenon. In principal diagnostic differentiation of species should always be based on comparison of otoliths from the same side. New fossil species belonging to genera which are known for their asymmetrical otolith morphology should preferably be established if and when otoliths of both sides are available. With the extensive material now available it is also possible to better understand the kinds and variations of asymmetry that can occur. There are a number of obvious regularities. First of all it is, with very few exceptions, the otolith of the eyed side that shows alterations from the “normal form”. Secondly, there are certain regular patterns or kinds of asymmetrical development, a fact which is helpful in the identification of isolated otoliths. These regularities were a surprising discovery since practically every character can be affected by asymmetry: – outline and proportions of the otolith, depth and width of the sulcus, separation or fusion of colliculi, opening of the ostium, development of an excisura, depth and width of the circumsulcal depression, curvature of the inner face. Also the degree of asymmetrical development can vary considerably from one genus to another (it is usually fairly consistent within a given genus). In many instances the alteration is not very strong and can readily be recognised even in isolated otoliths. In other words, even though left and right hand otoliths may look different it is usually not very difficult to tell which belong to the same species. This is of great importance for the paleontologist who has to deal with isolated otoliths. In close correlation with the recent findings I was able to identify left and right hand otoliths in practically every fossil species when they were both available. Even in those instances of more strongly developed asymmetry correlation with extant material usually solves the problem. In this respect it is interesting to note that the otoliths of the genus Rheinhardtius are amongst the ones with the most strongly developed side dimorphism. Paradoxically, this is the only pleuronectiform known to swim in a vertical posture (except for the “primitive” Psettodes). Of the 120 genera of living and fossil Pleuronectiformes of which otoliths have been studied 36 do not exhibit side dimorphism, corresponding to a fourth of all genera known by otoliths. These are representatives of the Psettodidae, Citharidae, Scophthalmidae (all except Lepidorhombus), Cynoglossidae and a number of genera from the families Bothidae and Soleidae. 9 additional genera of the Bothidae and Soleidae include species with asymmetrical otoliths (although usually very faintly so) and others with symmetrical ones. From a further 19 pleuronectiform genera only blind side otoliths are available and therefore their status in respect to symmetry remains questionable (most of these genera are from the Soleidae). Asymmetry of otoliths is established in at least 62 genera (including the 9 genera with occasional asymmetry), corresponding to about half of all investigated genera. Otolith asymmetry is particularly widespread in the Pleuronectidae, but is also known from several Bothidae and Soleidae. However, once otoliths of both sides are described from the 19 not investigated and the 19 single sided genera this number is likely to increase further. However, the effects of side dimorphism in most of these cases are not very dramatic. 17 genera show alterations of a single character only. Only 13 genera (about 10%) exhibit really pronounced otolith asymmetry. They are Lepidoblepharon (Brachypleuridae), Lepidorhombus (Scophthalmidae, fig. 14), Chascanopsetta (Bothidae, fig. 17), Eopsetta, Reinhardtius (fig. 20), Hippoglossoides, Lyopsetta, Glyptocephalus (fig. 22), Parophrys, Hypsopsetta, Rhombosolea (Pleuronectidae, fig. 21), Soleichthys and Dicologlossa (Soleidae, fig. Schwarzhans: Pleuronectiformes 49 23). As stated above, alterations usually occur in otoliths of the eyed side. Some exceptions to this rule seem to be manifested in the genera Cyclopsetta, Chascanopsetta (Bothidae), Hypsopsetta and Rhombosolea (Pleuronectidae). The various types of side dimorphism observed in pleuronectiform otoliths are described below. Descriptions centre on the alterations from the “normal” picture and usually refer to otoliths from the eyed side. The table below lists all the genera investigated and the various characters affected by asymmetry for each genus. Unfortunately, left and right hand otoliths are not known from every genus and such cases are marked accordingly on the list. Outline and proportions of otoliths. The most common type of asymmetry is observed in details of the outline of the otolith (45 genera). Usually, the outline of the altered otoliths (mostly from the eyed side) appear to be smoother and more uniform than those from the blind side (the reverse in Chascanopsetta, Hypsopsetta and Rhombosolea). The strongest type of alteration of the outline of the otolith is observed in the genera Chascanopsetta (fig. 17), Reinhardtius (fig. 20), Hippoglossoides, Hypsopsetta and Rhombosolea (fig. 21). Sometimes alteration of the outline is also reflected in the proportions of the otolith (length to height ratio; 5 genera). In this respect, otoliths of the eyed side are usually more elongate than those of the blind side. Sulcus and colliculi. Quite commonly otoliths from the eyed side slightly differ from those of the blind side in certain aspects of the sulcus morphology. Often, the sulcus is slightly narrower, sometimes also shorter and in few instances deeper. Also the proportions of ostium to cauda may be affected. Another common character is a reduced separation of the ostial and the caudal colliculum. Sometimes these are completely fused in otoliths of the eyed side whereas they are clearly separated in otoliths of the blind side. The most striking examples of this are found in the otoliths of Reinhardtius and Glyptocephalus. Side dimorphism in the morphology of the sulcus and/or colliculi is observed in 42 genera. The strongest alterations occur in Lepidoblepharon, Lepidorhombus (fig. 14), Reinhardtius (fig. 20), Hippoglossoides, Lyopsetta, Glyptocephalus (fig.22), Dicologlossa (fig. 23) and Soleichthys (in just one of two spePiscium Catalogus, Part Otolithi piscium, Vol. 2 cies). The soleid Dicologlossa is remarkable for the different sizes of its caudal colliculum which is larger in otoliths of the eyed side than in otoliths of the blind side. Sulcus opening and excisura. These characters are much less commonly affected by side dimorphism (11 genera). Where it occurs, otoliths of the eyed side usually exhibit a more clear cut opening of the ostium and a deeper excisura (the reverse in Rhombosolea). Chascanopsetta (fig. 17) and Rhombosolea (fig. 21) are the only genera in which this character is strongly developed. Circumsulcal depression and curvature of the inner face. This is another set of characters involved in side dimorphism. Often it is the most noticeable affected feature where it has been subject to alteration. At a low level of alteration the circumsulcal depression of the otolith from the eyed side may just be somewhat narrower or shallower than that of the blind side. Sometimes, however, it almost disappears in otoliths from the eyed side. In the more pronounced cases the surface of the circumsulcal depression, particularly its rear portion, is completely filled with sharp radial furrows and ridges the latter often exhibiting some kind of crystalline structure. At first sight the inner face of the otolith looks as if it has been eroded exposing the internal texture of the otolith at the surface. There are, however, few cases where this structure is developed in otoliths of both sides. Another character often combined with the reduction of the circumsulcal depression is a change in the curvature of the inner face, the inner face of otoliths from the eyed side becoming more convex. These characters, individually or in combination, are observed in 24 genera. Except for Rhombosolea they are only to be found in otoliths from the eyed side. They are most strongly developed in the genera Lepidorhombus (fig. 14), Eopsetta, Hippoglossoides and Parophrys (fig. 19). Key to the table listing asymmetrical development of otoliths: An asterisk (*) denotes alterations in otoliths of the blind side; a double-cross (#) on the eyed side. One mark corresponds to moderate alteration, two marks to strong alteration. A cross (+) is used in columns referring to general informations. Each character is coded by a number as follows. 50 1 2 3 4 5 6 7 = sulcus shape and/or depth = separation of colliculi = otolith proportions (l:h) = outline of the otolith = sulcus opening = excisura = depth, width and expression of the circumsulcal depression 8 = curvature of the inner face A question mark (?) indicates those cases, where the status of asymmetry is unknown, i.e. otolith is known from one side only. The abbreviation s. stands for symmetrical otoliths. ? Psettodidae Psettodes s. 1 2 3 4 5 6 7 8 + genera of uncertain relationship Tephrinectes + Paralichthodes + Collistium Ammotretis + Oncopterus + Citharidae Citharus Paracitharus Citharoides †Rhombocitharus + + + + Brachypleuridae Lepidoblepharon Brachypleura ## ## # Scophthalmidae Scophthalmus Lepidorhombus Zeugopterus Phrynorhombus Bothidae Ancylopsetta Gastropsetta Hippoglossina Xystreurys Lioglossina Paralichthys Pseudorhombus Tarphops Syacium Cyclopsetta Citharichthys Orthopsetta Etropus Bothus Parabothus Grammatobothus Neolaeops Arnoglossus # # + ## # # # ## ## + * + + # # + + + + + + + + + # # # # # * # # # + + + ? Pleuronectidae Eopsetta Hippoglossus Atherestes Cleisthenes Lyopsetta Acanthopsetta Hippoglossoides Reinhardtius Tanakius Glyptocephalus Limanda Dexistes Liopsetta Parophrys Pleuronectes Platichthys Kareius Pseudopleuronectes Lepidopsetta Inopsetta Psettichthys Isopsetta Verasper Clidoderma Microstomus Pleuronichthys Hypsopsetta Pelotretis Rhombosolea Plagiopsetta Samaris Samariscus Azygopus Marleyella Poecilopsetta Nematops Soleidae Trinectes Achirus Catathyridium Hypoclinemus Gymnachirus s. 1 2 3 4 5 6 7 8 # Caulopsetta Lophonectes Psettina Taeniopsetta Trichopsetta Engyophrys Laeops Monolene Asterorhombus Engyprosopon Crossorhombus Thysanopsetta Chascanopsetta Mancopsetta + # # + # # # + # # # # # # + # # * + # # # # * ** ## # # # # # # # # # # # # # # # ## ## # # # # ## ## ## # ## ## * # # # # ## # ## # # + + + + # # # # # # # # # # # # # juv. # # ## ## # # # + # # # # # + # # ** ** # # # # # * * * ** ** * * # # ## # # # # # + + # # # + + + + + + Schwarzhans: Pleuronectiformes 51 ? Nodogymnus Apionichthys Microchirus Monochirus Quenselia Dicologlossa Solea Microbuglossus Vanstraelenia Bathysolea Austroglossus Synaptura Heterobuglossus Dexillichthys Brachirus Anisochirus Phyllichthys Aesopia †Granulithus Soleichthys Pseudaesopia Zebrias †Praearchirolithus Aseraggodes †Pseudopardachirolithus Pardachirus Heteromycteris Rendahlia Peltorhamphus Cynoglossidae Cynoglossus Symphurus s. 1 2 3 4 5 6 7 8 + + # # # # # + # ## # + # # + + # # + + # + + + + + ## + + # # # 6.3 Variability and ontogenetic trends + + + + + # + more, as the example of Pleuronectes platessa shows, early ontogenetic side dimorphism may differ in character from that of adults (chapter 6.3). – I have made similar observations with otoliths of the genus Rhombosolea. There, quite dramatic changes in the nature of the side dimorphism apparently occurs much later in the ontogeny. Otoliths of 3 to 4 mm length usually exhibit a rather distinct rostrum and often a clear sulcus opening, both particularly in otoliths of the blind side (side dimorphism). In otoliths of 5 mm of length and more rostrum and sulcus opening are reduced or practically absent. Side dimorphism now finds its expression in differences in the outline, otolith proportions, curvatures and presence of an excisura on blind sided otoliths. In fact, side dimorphism is quite strong in both ontogenetic stages observed. # * + Some good examples of side dimorphism in otoliths are shown in figs. 14-23. More detailed remarks and figures are found in the descriptive section, when and where side dimorphism has been investigated. It is not yet known in which ontogenetic stage side dimorphism of otoliths may begin to develop. However, one would expect it to occur earliest in postlarval stages when the fish settles on the bottom and the other asymmetrical characters are being developed. Otoliths of pelagic larval stages with which to examine this hypothesis are, however, unknown. I have investigated otoliths of early postlarval fishes from Pleuronectes platessa (TL = 27-60 mm). They do already show some kind of incipient side dimorphism (see chapter 6.3). Realising that the patterns of side dimorphism of otoliths are quite different in many of the flatfish genera it seems also likely that it may begin to develop at different ontogenetic stages. FurtherPiscium Catalogus, Part Otolithi piscium, Vol. 2 The intraspecific variability in flatfish otoliths is high; higher than in otoliths of most other Teleost groups. A good impression of the range of this variation may be gained from a number of pleuronectiform species, both recent and fossil, figured by CHAINE (1936) and in this treatise. NOLF (1985) noted that although the intraspecific variability is unusually high in flatfishes the characters of individual species can still be recognised if one has a good series of otoliths. SCHWARZHANS (1984) remarked that particularly in the Soleoidei, where the morphology of otoliths is strongly reduced, there may exist cases where otoliths of related species are not always distinguishable. It now appears that the degree of intraspecific variability is quite different from one group of flatfishes to another. For instance groups with a relatively low degree of variability are the Psettodidae, Brachypleuridae, the Paralichthys, Pseudorhombus, Citharichthys and Syacium Groups of the Bothidae, most Pleuronectidae except for the Microstomus-Pleuronichthys Group, the Brachirus, Zebrias, Synaptura and Pardachirus Groups of the Soleidae and the Cynoglossus Group of the Cynoglossidae. Groups with a high degree of intraspecific variability are the Citharidae, most Scophthalmidae, the Bothus and Arnoglossus Groups of the Bothidae, the Microstomus-Pleuronichthys Group of the Pleuronectidae, the Solea and part of the Heteromycteris Groups of the Soleidae and 52 part of the genus Symphurus of the Cynoglossidae. In particular otoliths of the species-rich genera Bothus, Arnoglossus, Engyprosopon, Laeops, Monolene (Bothidae), Microchirus, Solea (Soleidae) and Symphurus (Cynoglossidae) are at times very difficult to differentiate accurately to species level. Also defining features for a reliable differentiation of related genera sometimes presents some difficulties and then remains very tentative. In the fossil record of these genera we must be prepared to deal with “morphological species groups” rather than with defined species, at least in some cases (see for instances entries to Microchirus frequens, Microchirus kirchbergeanus or Symphurus atricaudus). Other species-rich genera with a much lower degree of intraspecific variability and a better morphological differentiation do allow for a relatively well established taxonomic analysis, for instance Paralichthys, Pseudorhombus, Citharichthys (Bothidae) or Cynoglossus (Cynoglossidae). The characters most commonly affected by intraspecific variability are those of the outline of the otolith and its proportions. This is particularly true for otoliths with a much reduced morphology. Unfortunately, these characters are often important for distinguishing between closely related species. It is advisable for the paleontologist wishing to identify fossil pleuronectiform otoliths to proceed very carefully in those cases (see list of genera above) and adopt a “conservative” interpretation habit (see also chapter 4.1). – Other characters such as details of the sulcus morphology, thickness or curvatures may vary as well, but usually to a much lesser degree. Ontogenetic changes, as in almost any other Teleost group, play a very important role in the Pleuronectiformes and these are often of greater magnitude than the differences due to intraspecific variability. Otoliths of pelagic larval stages are unknown. However, I have investigated otoliths from early bottom-living postlarval stages of Pleuronectes platessa and Samariscus triocellatus. Those of Pleuronectes platessa came from fishes of 27 to 60 mm TL which were probably between 4 and 8 months old. Otolith sizes are 1.0 to 1.6 mm. They differ from adults in many aspects of the outline, but already show the typical pleuronectiform circumsulcal depression. Also the sulcus opening is already much reduced. They even exhibit a very faint side dimorphism as far as the development of the posterior tip of the otolith is concerned (see chapter 6.2), which is obscured and replaced by other asymmetrical characters in adults. A similar observation occurring somewhat later in ontogeny is observed in Rhombosolea tapirina and R. plebeia. Left hand otoliths in the category up to 5 mm show a pronounced rostrum which is absent in right hand otoliths of the same size. In larger specimens from 5 mm or greater, the rostrum is reduced in otoliths of both sides. Instead left hand otoliths have developed some kind of irregular excisura. This indicates that side dimorphism, at least in some cases, may develop very early in ontogeny and then it may be subject to radical change as a process of subsequent development. In general, most juvenile otoliths exhibit a much more generalised morphology than do adults and in many cases (e.g. if found isolated) these can only be identified in the context of a well established ontogenetic succession. Characters affected are mostly those concerning features of the outline of the otolith and its proportions, curvature of the inner face and thickness. But also certain aspects of the sulcus characters may at times show allometric ontogenetic growth. In the case of mixed lots of closely related species, their respective juvenile representatives may not be distinguishable at all (see for instance entries to Arnoglossus novus and A. longus). Attempts to identify juvenile pleuronectiform otoliths should therefore be restricted to those cases from which sufficient ontogenetic successions are known. In palaeontology the creation of doubtful flatfish records on the basis of juvenile otoliths has become a problem. It is imperative that new fossil species or new records (both geographic or stratigraphic) are based on adult specimens which have reached a certain minimum size that guarantees that valid diagnostic characters have been developed. Since flatfishes and their corresponding otoliths grow to quite different sizes it is necessary to define such minimum sizes separately for each genus or genus group. For example, an adult otolith of the genus Hippoglossus may reach 10 to 15 mm in length, an adult Arnoglossus otolith ranges from 2 to 4 mm, and an adult Apionichthys otolith may be just slightly over 1 mm. Wherever available data have permitted the definition of minimum diagnostic size I have done so in the following systematic part. Usually, otoliths of the Pleuronectiformes are fairly large when compared to the size of the fish, Schwarzhans: Pleuronectiformes 53 with one notable exception: that of the Ammotretis Group, which have comparatively small otoliths. 6.4 Otoliths of reversed specimens (Fig. 24-26) In the great majority of flatfishes all the individuals of a particular species and genus are either right-sided (dextral) or left-sided (sinistral). NORMAN (1934) has used this character as one of the key parameters to define several families, such as the Bothidae (sinistral eyes), Pleuronectidae (dextral eyes), Soleidae (dextral eyes) and Cynoglossidae (sinistral eyes) (see also chapter 5.3.2). Some of the more primitive members – Psettodidae, Tephrinectes, Hippoglossina – are indifferently dextral or sinistral. These are also groups that do not exhibit side dimorphism in otoliths. However, reversal, or the occurrence of individuals with the eyes and colouring on the side which is generally eyeless and unpigmented in the species, is a not uncommon phenomenon in certain other flatfishes as well, including some species showing pronounced side dimorphism in otoliths. One of the genera known for common occurrence of reversed specimens is Platichthys. Platichthys stellatus in particular is known for almost invariably reversed (sinistral) specimens in the waters around Japan, whereas in California the number of dextral and sinistral individuals is about equal (NORMAN, 1934). Otoliths of the two species of Platichthys (P. flesus and P. stellatus) and a specimen from Rhombosolea tapirina from the BMNH collection were selected to investigate the influence that reversal might have on the morphology of their otoliths already known for pronounced side dimorphism. In these specimens it was found that reversal of the fish does not mean that the features of the otolith morphology affected by side dimorphism become simply reversed as well. In other words, the otolith of the right (blind) side of a reversed individual from a sinistral specimen does not necessarily resemble the otolith of the left (blind) side of a non-reversed individual from a dextral specimen (and neither do the otoliths of the respective eyed sides). In Platichthys stellatus (fig. 24), however, one character is indeed developed in mirror image, and this is the reduced separation of the colliculi Piscium Catalogus, Part Otolithi piscium, Vol. 2 in otoliths of the eyed side (right side in normal specimens and left side in reversed individuals). With that exception side dimorphism does not become transformed. In fact in otoliths of reversed individuals the typical side dimorphic features characteristic of the non-reversed individuals become less pronounced and both sides come to resemble each other more closely. More intriguingly, otoliths of reversed specimens exhibit a different habitus than those of non-reversed individuals. Reversed specimens from California show much more elongate otoliths than non-reversed, whereas reversed specimens from the West Pacific show more compressed otoliths than non-reversed ones. Clearly, when investigated as isolated otoliths (for instance in the fossil record) these three morphotypes would have been attributed to three different species. In Platichthys flesus (fig. 25), reversal has a less pronounced effect on otolith morphology. Otoliths of reversed specimens have practically lost all the side dimorphic features (including the lack of separation of the colliculi, see above) and are almost completely symmetrical (resembling otoliths of the blind, left side of non-reversed individuals). Apart from that they do not differ much from those of non-reversed specimens. The single reversed specimen of Rhombosolea tapirina (fig. 26) investigated shows otoliths which are much more compressed than those of nonreversed individuals. Also the morphology of the sulcus is somewhat distorted. The typical side dimorphic features observed in non-reversed specimens are lacking. As with Platichthys stellatus the otoliths of the reversed specimen would probably be attributed to a separate species if analysed in isolation. It can be concluded from these investigations that reversal has quite different effects on otolith morphology from one species to another, is unpredictable in morphological terms and needs to be investigated separately for each species. From the otolith morphology alone it can not be judged whether a given otolith has originated from a non-reversed “normal” individual or a reversed one. For the paleontologist dealing with isolated otoliths it means once again that he or she should deal very carefully with unique aberrant specimens of genera known for side dimorphism in otoliths (practically all Pleuronectidae and many Bothidae). They could represent “distorted” otoliths of a reversed specimen (or else teratological effects). It will, however, become difficult in those 54 Platichthys stellatus dextral (normal) from California sinistral (reversed) from California sinistral (reversed) from NW-Pacific 24 Schwarzhans: Pleuronectiformes 55 Platichthys flesus dextral (normal) sinistral (reversed) very few instances, where reversal occurs regularly in side dimorphic otoliths as, for example, in the recent Platichthys stellatus. Although this phenomenon appears to occur extremely rarely (at least in recent flatfishes) it must still be born in mind that clearly distinct flatfish otolith morphologies do not necessarily represent different species in every case. 25 6.5 Sexual dimorphism The differences between the sexes in certain genera and species is most marked in the overall external morphology, especially in the family Bothidae and certain Pleuronectidae. Various characters may be involved such as scales, rostral and orbital spines, interorbital width, form of fins, Rhombosolea tapirina dextral (normal) sinistral (reversed) 26 Figs. 24-26: Examples of otolith morphology in reversed and normal specimens of Pleuronectiform fishes – fig. 24 Platichthys stellatus, fig. 25 Platichthys flesus, fig. 26 Rhombosolea tapirina. Piscium Catalogus, Part Otolithi piscium, Vol. 2 56 coloration, and (in Marleyella bicolorata) the teeth (NORMAN, 1934). In some instances sexual dimorphism is such that males and females of a single species were originally described as separate species (see entry for Syacium ovale). In otoliths, sexual dimorphism has been observed only very rarely (SCHWARZHANS 1994). In the case of the Pleuronectiformes I have checked several species with external sexual differences (Bothidae, Marleyella) for corresponding sexual dimorphism in the otoliths. Marleyella, which was noted by NORMAN (1934) as a flatfish with a very peculiar type of sexual dimorphism, did not show any sexual differences in their otoliths. The same is true for practically all Bothidae investigated in this respect. A possible exception is Syacium ovale. In that species, it seems that otoliths from females differ from those of males in having less ornamented rims and a pronounced postdorsal concavity. This, however, is only true for otoliths of the blind side (right side); those of the eyed (left) side can not be distinguished. In this respect it is interesting to note that Syacium ovale is one of the bothid species with strongly enlarged interorbital width in males. Other genera with such a sexually dimorphic development of the interorbital width, chiefly of the Bothus and Engyprosopon Groups, either could not be checked for otoliths or gave inconclusive results. Nevertheless, I think it is quite possible that sexually dimorphic interorbital widths may express themselves in sexually dimorphic otoliths as well. This subject needs further investigation. Otoliths of the species of the Samaris Group often exhibit two quite distinct morphologies. One morphology is characterised by a more compressed appearance, a clear excisura and rostrum and strongly ornamented rims, whereas the other morphology is more elongate, with a reduced excisura, rounded rostrum and a more regularly curving and smooth outline. This phenomenon is observed in Plagiopsetta and Samaris (see respective entries), and may also be expected in the third genus of the group – Samariscus. None of these genera is known for external sexual differences. Nevertheless, I suspect that the two morphologies observed in otoliths possibly might represent such sexual dimorphism. (In the few instances of known sexual dimorphism of otoliths sexual differences of external characters likewise are usually inconspicuous; see SCHWARZHANS 1994.) Unfortunately, I was not able to verify this hypothesis by identifying the sexes of the specimens involved. The fishes of Samaris from which the otoliths have been taken (coll. IRSNB) could not be traced and the specimens of Plagiopsetta could not be identified to sex. Schwarzhans: Pleuronectiformes 57 7. Descriptive Part Abbreviations used: l:h = otolith length to otolith height h:t = otolith height to otolith thickness ol:cl = ostium length to cauda length oh:ch = ostium height to cauda height s.i.a. = sulcus inclination angle con.i. = convexity index of inner face (otolith length /2 to thickness of inner face in ventral view) con.o. = convexity index of outer face (otolith length /2 to thickness of outer face in ventral view) Synonymy listings for recent fishes only include primary synonyms and are mostly based on NORMAN (1934) for Pleuronectoidei and MENON (1978) for Cynoglossus. Other references (Soleoidei) are based on various sources and listings may not be complete. Synonymy listings for fossil otolith based species are as complete as possible. However, secondary references are only included if either checked with original specimens or if figures in literature are detailed enough to allow identification. Thus a number of questionable or not verified secondary references are omitted for the time being. 7.1 Psettodidae Genera: The family Psettodidae contains but a single recent genus – Psettodes – with two recent species, one from tropical West Africa, the other from East Africa and the Red Sea to the western Pacific. Two fossil otolith based species have been recorded from the Eocene of Belgium and France. Joleaudichthys CHABANAUD 1937, a fossil skeleton based genus from the Middle Eocene of Egypt, may also be placed in the Psettodidae (HUBBS 1945). Definition and relationship: NORMAN (1934) has worked out in great detail the very “primitive” nature of the genus Psettodes. Plesiomorphic characters include the high degree of symmetry (pelvic fins, nasal organ, lateral line, dentition), the indifference in left and right eyed individuals, the low number of anal (< 45) and dorsal (< 60) Piscium Catalogus, Part Otolithi piscium, Vol. 2 fin rays, the presence of a spine in the dorsal and pelvic fins, the tip of the dorsal fin situated behind the nostrils, and the dimorphic optic chiasma. Psettodes frequently swims in an upright posture . The only autapomorphic character that NORMAN was able to identify is the absence of gill rakers. Otoliths likewise are characterized by a number of plesiomorphic features, such as the distinct anterior opening of the sulcus, the long and narrow cauda with its slightly inclined caudal tip, and the incomplete circumsulcal depression (see also chapter 5.2). Discussion: As suggested on various occasions (see chapter 5.2) Psettodid otoliths strongly resemble certain percoid otolith patterns. Otolith analysis supports NORMAN’s concept of the very plesiomorphic nature of the Psettodidae with respect to the other pleuronectiforms and their origin from a percoid stock. Psettodidae represent the earliest fossil records of the flatfishes (together with a few other primitive genera) dating back, at least, to Early Eocene times. Otolith morphology has not changed much since then. Psettodes BENNETT 1831 Type-species: Psettodes belcheri BENNETT 1831 syn. Sphagomorus COPE 1869 (type-species: Pleuronectes erumei) Diagnosis: Thin, elongate otoliths; ventral rim gently curving, dorsal rim with distinct pre- and postdorsal angles, posterior tip pointed, angular; index l:h 1.6 to 2.6. Ostium widened, anteriorly open, shallow, shorter than cauda. Cauda long, narrow, somewhat deepened, with pointed and slightly inclined posterior tip. Index ol:cl < 1.0. Dorsal and ventral depression not connected around caudal tip, not forming a circumsulcal depression. Ventral depression rather short. Inner face slightly convex; outer face slightly concave, with some radial ornamentation. Rims sharp, thin, often crenulated (particularly the ventral rim). 58 Measurements: belcheri (ad.) belcheri (juv.) erumei (ad.) erumei (juv.) † collatus † bavayi l:h 2.15-2.60 1.80-2.00 2.00-2.15 1.65-1.85 1.65-1.75 1.80 h:t >3.5 >3.5 >3.5 >3.5 3.5 3.0 ol:cl 0.75-0.95 0.95 0.90 0.75-0.95 0.85-1.05 0.70 oh:ch 1.8-2.2 1.9 1.8 2.0-2.6 1.9-2.2 1.6 con.i about 6 about 6 about 6 about 5 about 4 about 6 Side dimorphism: Not apparent. Variability and ontogeny: CHAINE (1936) has figured a large series of otoliths of the two recent species. From his illustrations it appears that the variability in this genus is relatively moderate, restricted to slight variations in outline and otolith proportions. Ontogenetic changes are much stronger as shown in the figures to both recent species. Smaller otoliths as a rule are considerably more compressed than larger otoliths. The smallest specimen figured is about 5 mm long. It already exhibits good diagnostic characters, but only otoliths from 6 to 7 mm onward seem to have developed the full set of pertinent diagnostic features. Otoliths from truly adult fishes are in the range of 10 to 15 mm. Species and distribution: Two recent species: P. belcheri from the tropical west African coast and P. erumei ranging from East Africa to the tropical western Pacific. Two fossil species: P. collatus and genus aff. Psettodes bavayi from the Lower Eocene of the Aquitaine Basin (France) which is tentatively placed in this genus. The latter is even more plesiomorphic in several characters and may very well represent an extinct fossil genus. In addition STEURBAUT (1984) has recorded a Psettodes sp. from the Lower Miocene of France (Aquitaine Basin). Psettodes belcheri BENNETT 1831 Figs. 27-29 ontogenetic stage. Also the ostium is usually narrower and the marginal crenulation more irregularly developed. Illustrations in CHAINE (1936) exhibit a notable trend to develop “fenestrate” otolith margins. Distribution: Tropical West Africa, at shallow depth. Psettodes erumei (SCHNEIDER 1801) Figs. 30-31 syn. Pleuronectes nalaka CUVIER 1829 syn. Hippoglossus dentex RICHARDSON 1845 syn. Hippoglossus orthorhynchus RICHARDSON 1846 syn. Hippoglossus goniographicus RICHARDSON 1846 Investigated otoliths: Three otoliths, one (right side, fig. 30) from Western Australia, ZMH Ot. 1.12.1993.1 (coll. Schwarzhans, leg. WAM), one (left side, fig. 31) from off Orissa, India, BMNH 1927.1.6.1, one (left side) from the Persian Gulf off Saudi Arabia, BMNH 1987.2.12.29. Discussion: Otoliths of P. erumei are more compressed than those of P. belcheri of the same size and more regularly ornamented. The ventral rim is more deeply curving, often with an obtuse midventral angle. Distribution: Red Sea and Indo-West-Pacific from South Africa to Australia and Japan, in shallow water. Psettodes collatus NOLF 1972 Figs. 32-39 Investigated otoliths: 3 otoliths, one (left side, fig. 27) IRSNB (coll. Nolf), one (right side, fig. 28) from off Lagos, Nigeria, BMNH 1914.11.2.73, one (left side, fig. 29) from off Accra, Gold Coast, BMNH 1930.3.24.43. syn. Psettodes collatus NOLF 1972 – NOLF 1972a: fig. 25 syn. Psettodes oedelemensis NOLF 1972 – NOLF 1972b: pl. 3, fig. 5-6 syn. Psettodes oedelemensis – NOLF 1972c: pl. 2, fig. 24 syn. Psettodes spinosus NOLF 1972 – NOLF 1972c: pl. 2, fig. 25 syn. Psettodes sp. – NOLF 1988: pl. 14, fig. 2 Discussion: Otoliths of P. belcheri are always more elongate than those of P. erumei of the same Investigated otoliths: 8 otoliths, the holotype of P. collatus (fig. 32; IRSNB P 2221) from the Ledian syn. Psettodes bennettii STEINDACHNER 1870 Schwarzhans: Pleuronectiformes 59 28 27a 27b 29 30a 31a 31b 30b Figs. 27-29: Psettodes belcheri BENNETT 1831 – 6 × Figs. 30-31: Psettodes erumei (SCHNEIDER 1801) – 6 × (Middle Eocene) of Balegem (Belgium), a paratype of P. collatus (fig. 37; IRSNB P) from the Middle Eocene of Meldert (Belgium), two further specimens from Balegem (figs. 33-34; IRSNB P 2163-2164), the holotype of P. oedelemensis (fig. 39; IRSNB P 2261) from the Sands of Oedelem (Middle Eocene) of Oedelem (Belgium) and the paratype of P. oedelemensis (fig. 38; IRSNB P 2262) from the Calcier Grossier (Middle Eocene) of Fercourt (France), the holotype of P. spinosus (fig. 35; IRSNB P 2314) from the Calcier Grossier (Middle Eocene) of Fercourt (Paris Basin, France) and the specimen described as P. sp. by NOLF (1988) (fig. 36; IRSNB P 4518) from the Ypresian (Lower Eocene) of the tuilerie de Gan (Aquitaine Basin, France). Ontogeny and variability: The specimens investigated are between 2.5 and 5.5 mm in size. The smaller specimens (figs. 32-36) are somewhat more generalized in outline as the larger ones Piscium Catalogus, Part Otolithi piscium, Vol. 2 (figs. 37-39) and show more delicately ornamented rims. The largest specimens, including a paratype of P. collatus (fig. 37) and the holotype and paratype of P. oedelemensis (figs. 38-39) show a tendency to reduce the intensity of the marginal crenulation and develop a more accentuated postdorsal angle. Variations in morphology are restricted to relatively few characters. These are the strength of the marginal crenulation and development of the postdorsal angle, which usually is quite rounded, and the strength of the caudal curvature. Discussion: The holotype of P. collatus is of moderate size and perfectly preserved. It is a typical specimen of the genus Psettodes, quite similar to the recent P. erumei. The main difference to the recent species is the more rounded postdorsal angle and the blunt posterior tip. 60 32a 33 32b 34 35a 35b 36 Figs. 32-36: Psettodes collatus NOLF 1972 – 15 × Similar otoliths have been described by NOLF from the Middle Eocene of Belgium and France as P. oedelemensis and P. spinosus. The latter is based on a unique and very small type-specimen which I find to fit perfectly with specimens of P. collatus of the same size. This specimen and also the one described by NOLF (1988) in open specific nomenclature from the Lower Eocene of the Aquitaine Basin therefore are synonymized with P. collatus. P. oedelemensis is based on two much larger specimens (5.5 mm), which both show a pronounced postdorsal angle and a much lesser degree of marginal crenulation. However, both characters are likely to be the result of allometric ontogenetic changes, similarly to the specimens of the two recent species as figured by CHAINE (1936). Furthermore, the holotype of P. oedelemensis is slightly eroded marginally, which no doubt has influenced the marginal ornamentation. The large paratype of P. collatus from Meldert is the only specimen of this nominal species in compa- rable size. It too is somewhat eroded marginally resulting in a similar intensity of the ornamentation as seen in the holotype of P. oedelemensis. The only difference is the weaker postdorsal angle, but this too could be an erosional effect. In the light of allometric ontogenetical changes this singular character does not warrant the separation of two species of the genus Psettodes occurring simultaneously in stratigraphy and geography. As it stands now, I have little doubts that P. spinosus, P. collatus and P. oedelemensis simply represent different ontogenetic stages of a single species. P. collatus deserves priority over P. oedelemensis and P. spinosus as the first species that has been described by NOLF in a series of three subsequent publications in the same year, all dealing with Eocene otoliths from Belgium and France. Distribution: Lower Eocene of the Aquitaine Basin (France) and Middle Eocene of Belgium and the Paris Basin (France). Schwarzhans: Pleuronectiformes 61 37 38a 38b 39 Figs. 37-39: Psettodes collatus NOLF 1972 – 15 × genus aff. Psettodes bavayi NOLF 1988 Figs. 40-41 syn. Psettodes bavayi NOLF 1988 – NOLF 1988: pl. 14, fig. 1 Investigated otoliths: 2 otoliths, the holotype (fig. 40, IRSNB P 4517) and the paratype (fig. 41, IRSNB P) both from the Ypresian (Lower Eocene) Piscium Catalogus, Part Otolithi piscium, Vol. 2 of tuillerie de Gan (Aquitaine Basin, France). Ontogeny and variability: The paratype is about half the size of the holotype and differs in showing a less pronounced postdorsal angle and a delicately crenulated rim. Discussion: This species is known only from two relatively small otoliths. The holotype is about 62 41 40a 40b Figs. 40-41: Psettodes bavayi NOLF 1988 – 15 × 3.3 mm in size, the paratype 2.0 mm. Nevertheless, g. aff. P. bavayi is easily recognized by the following characters – the elongate shape, the pronounced postdorsal angle in combination with the vertically cut posterior rim, the narrow ostium and the rather strongly bent cauda. Without the ventral depression being present, these otoliths perfectly resemble certain Percoidei. In fact, g. aff. P. bavayi represents the most plesiomorphic otolith pattern so far observed in Pleuronectiformes. In my opinion it probably represents an extinct and very basal Pleuronectiform genus. Closest resemblance no doubt is to Psettodes (where this species is now preliminarily being placed) and also Paralichthodes. The latter is surprisingly similar in outline, the narrow ostium and the very feeble ventral depression. Main difference is the deepened and widened caudal tip in the recent otoliths of Paralichthodes algoensis. Distribution: Lower Eocene of the Aquitaine Basin (France). 7.2 Genera of uncertain relationship Remarks: In this category I have provisionally put together a few genera with very plesiomorphic otolith patterns, which in the past have been placed in the Bothidae or Pleuronectidae respectively. They are: Tephrinectes from Bothidae, Paralichthodes from Pleuronectidae (subfamily Paralichthodinae of NORMAN 1934), Colistium, Ammotretis, Oncopterus and possibly also Psammodiscus and Taratretis from Pleuronectidae (subfamily Rhombosoleinae of NORMAN 1934). Their otoliths resemble those of psettodids and citharids, and otolith-only studies would suggest alternative classification. However, since character analysis of the otoliths is based on plesiomorphic features alone I have selected to present them in open familial nomenclature. Additional ichthyological analyses (f.i. osteological) will be needed before an adequate taxonomic allocation of these problematic genera can be formulated. However, recently HENSLEY & AHLSTROM (1984) have suggested a similar position regarding the genus Tephrinectes. As far as otolith analysis is concerned, it is suspected that the phylogenetic divergence of these genera occurred before the origin of the Bothidae or Pleuronectidae in which they have traditionally been placed. Some characters such as the long and slightly inclined cauda and the very incomplete circumsulcal depression are more primitive than the pattern found in the Citharidae, which may be regarded as the plesiomorphic sister-group of Scophthalmidae, Bothidae and Pleuronectidae (see also entry for Citharidae). The genera placed in this category of open familial nomenclature fall readily into three genus groups - the Tephrinectes Group, the Paralichthodes Group (both monogeneric) and the Ammotretis Group (for definitions see respective entries). This grouping is different from that proposed by NORMAN, and suggests also that these genera are not in fact closely related. Their otoliths share plesiomorphic features. 7.2.1 Tephrinectes Group Genera: One genus – Tephrinectes – with one recent species from the coasts of China. Definition and relationship: Otoliths of Tephrinectes are very similar to those of Psettodes. However, this similarity is based on plesiomorphic characters such as the clear anterior opening of the sulcus, the long an narrow cauda with its slightly inclined tip and the incomplete circumsulcal depression. The only difference of any Schwarzhans: Pleuronectiformes 63 importance is the index: ostium length to cauda length (ol:cl) which is 1 or slightly more. Clearly this is one of the most plesiomorphic otolith patterns to be found in pleuronectiforms next to the Psettodidae. According to NORMAN’s detailed description the fish itself exhibits a number of primitive characters as well. These are the indifference of left and right eyed individuals, the low number of anal (< 40) and dorsal fin rays (< 50), the tip of the dorsal fin situated behind the nostrils, and the olfactory laminae with a long rachis. These are all plesiomorphic characters which Tephrinectes shares with Psettodes. More advanced, in comparison with Psettodes, is the monomorphic optic chiasma, the asymmetrical nature of the nasal organ, and the loss of spines in the dorsal and anal fins. NORMAN (1934) placed Tephrinectes in the family Bothidae, but judging by its position as the first genus listed in the family Bothidae, he probably regarded it as a primitive genus. Otolith analysis suggests even a pre-bothid origin of the genus. This agrees with the suggestion put forward by HENSLEY & AHLSTROM (1984). In a cladogram it may be placed close to the Citharidae or between Psettodidae and Citharidae. Measurements: sinensis l:h h:t ol:cl 1.65-1.80 about 4 1.0-1.3 oh:ch 1.5-2.0 con.i about 4 Side dimorphism: Not apparent. Species and distribution: A single living species: T. sinensis from the coasts of China. Tephrinectes sinensis (LACEPEDE 1802) Figs. 42-45 Investigated otoliths: 4 otoliths, one (left side, fig. 42) from Hongkong, BMNH 1939.3.23.90, one (right side, fig. 43) from China, BMNH 65.5.2.29, two (left and right side, figs. 44-45) from Fokien, China, ZMH 20003. Ontogeny and variability: The largest otolith available is 6 mm long (fig. 42). Smaller otoliths of about 2.5 mm length (figs. 44-45) are much more intensely and irregularly crenulated along the rims. They are still identifiable, but I would assume that only otoliths larger than 4 mm (fig. 43) have developed all pertinent diagnostic characters. Distribution: Coasts of China. Tephrinectes GÜNTHER 1862 Type-species: Pleuronectes sinensis LACEPEDE 1802 syn. Tephrites GÜNTHER 1862 (preocc.; type-species: Pleuronectes sinensis) syn. Velifracta JORDAN 1907 (type-species: Pleuronectes sinensis) Diagnosis: Thin, moderately elongate otoliths; ventral and dorsal rims gently curving, posterior tip blunt, anterior tip with rostrum somewhat more pointed; index l:h 1.65 to 1.8. Ostium somewhat widened, anteriorly open, shallow, about as long as cauda. Cauda narrow, somewhat deepened, with pointed and slightly inclined posterior tip. Index ol:cl 1.0 to 1.3. Dorsal and ventral depression not connected around caudal tip, not forming a circumsulcal depression. Ventral depression feeble. Inner face moderately convex; outer face slightly concave, with some radial ornamentation. Rims sharp, thin, crenulated. Piscium Catalogus, Part Otolithi piscium, Vol. 2 7.2.2 Paralichthodes Group Genera: One genus – Paralichthodes – with one recent species from the coasts of South Africa. Definition and relationship: Otoliths of Paralichthodes are very similar to those of Psettodes and Tephrinectes in many plesiomorphic characters. These are the clear anterior opening of the sulcus, the long an narrow cauda with its inclined tip and the incomplete circumsulcal depression. Like in Psettodes the ostium is markedly shorter than the cauda. The inclination of the caudal tip is even stronger than in Psettodes, and in fact the strongest of its kind to be found in flatfishes. Clearly this is one of the most plesiomorphic otolith patterns to be found in Pleuronectiformes next just to Psettodidae. Paralichthodes is always right eyed. In shape and general appearance it resembles the left eyed Citharidae but also the right eyed Brachypleuridae. Most other characters of Paralichthodes are 64 43 42a 44 42b 45 42c Figs. 42-45: Tephrinectes sinensis (LACEPEDE 1802) – 10 × not particularly primitive except for the olfactory laminae with the long rachis. NORMAN (1934) had placed Paralichthodes in the family Pleuronectidae, but in a separate subfamily Paralichthodinae. In recent literature Paralichthodes is often associated with another Pleuronectid subfamily, the Samarinae (NELSON 1984), however, HENSLEY & AHLSTROM (1984) regarded this genus as a Pleuronectid of uncertain relationship. As it seems otoliths point to a radically different systematic allocation, possibly close to or within the Citharidae. The only reason that makes me hesitate is the fact that Citharidae are left eyed. The right eyed Brachypleuridae would have been an alternative. They have been regarded as a subfamily of the Citharidae by HUBBS (1945), who established the family. However, otoliths of Brachypleura and Lepidoblepharon have nothing in common with those of Paralichthodes (see respective entry). Paralichthodes GILCHRIST 1902 Type-species: Paralichthodes algoensis GILCHRIST 1902 Diagnosis: Thin, moderately elongate otoliths; ventral rim gently curving, posterior and anteri- or tips broadly rounded, blunt; index l:h 1.6 to 1.8. Ostium widened, anteriorly open, somewhat deepened, considerably shorter than cauda. Cauda long, narrow, with rounded and inclined posterior tip. Index ol:cl 0.75-0.85. Dorsal and ventral depression not connected around caudal tip, not forming a circumsulcal depression. Ventral depression extremely indistinct; dorsal depression also very shallow. Inner face slightly convex; outer face slightly concave, smooth. Rims sharp, thin, smooth to slightly undulating. Measurements: algoensis l:h h:t ol:cl 1.6-1.8 about 4 0.75-0.85 oh:ch con.i 1.6-1.7 about 3.5 Side dimorphism: Not apparent. Species and distribution: One recent species – P. algoensis from the coasts of South Africa. There is also fossil otolith based species from the Lower Eocene of France – genus aff. Psettodes bavayi (NOLF 1988) which bears a lot of resemblance with P. algoensis and alternatively could be placed in this genus as well (for details see entry to g. aff. Psettodes bavayi). Schwarzhans: Pleuronectiformes 65 47a 46 47b Figs. 46-47: Paralichthodes algoensis GILCHRIST 1902 – 15 × Paralichthodes algoensis GILCHRIST 1902 Figs. 46-47 Investigated otoliths: 2 otoliths (left and right side) from off Durban, South Africa, BMNH 1919.9.12.48. Remarks: Both extracted otoliths have been somewhat affected by formalin. In particular the dorsal rim is incomplete. Other characters, however, in particular those of the sulcus are very well preserved. Recently, SMALE et al. (1995) have figured two complete specimens of this species, wich support above analysis, figures and descriptions. Otolith size is only about 3.5 mm but pertinent diagnostic features seem to be fully developed. Distribution: South Africa, from Mossel Bay to Delagoa Bay in 1-100 m. 7.2.3 Ammotretis Group Genera: In this group I have united the genera Colistium, Ammotretis, Oncopterus, Psammodiscus and Taratretis of NORMAN’s Rhombosoleinae. Psammodiscus, of which otoliths are unknown, is placed here because NORMAN has regarded it as related to Oncopterus, and so is Taratretis which has been erected more recently. Azygopus (of Pleuronectidae, see respective entry) could also alternatively be placed in this group and was included in the Rhombosoleinae by NORMAN. All these genera are endemic to the southern oceans, chiefly around Australia and New Zealand except for Oncopterus which occurs along the coasts of southeastern South America. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Definition and relationship: Otoliths of the Ammotretis Group are characterized by a unique combination of very plesiomorphic and (aut)apomorphic characters. Plesiomorphic characters are the clear sulcus opening, the somewhat widened ostium, the narrowed cauda which usually is slightly longer than the ostium, and the extreme feeble development of the incomplete dorsal and ventral depression. I would think that these otoliths may not have been recognized as representatives of Pleuronectiformes when investigated isolated and without the knowledge of the fishes from which they have been extracted. Apomorphic characters are the development of the caudal tip which is widened in Colistium and pointed in a very distinctive way in Ammotretis and Oncopterus. Also these otoliths are extremely small in comparison to the size of the fish or the head. Otoliths extracted from Oncopterus darwini and Ammotretis elongatus of a SL of more than 200 mm was found to be less than 2 mm long. Otolith of similar sizes are found in Pleuronectids, Bothids, Soleids or Cynoglossids in fishes the size of 40 to 80 mm (taking head proportions into consideration this disproportion would even become larger). The fishes themselves, however, are by no means plesiomorphic in appearance. In fact, Ammotretis and Colistium were noted by NORMAN (1934) to be the ones exhibiting some superficial resemblance with Soleids which he regarded as a convergent evolution. (Another genus mentioned in this respect was Peltorhamphus, which according to otolith analysis indeed should be placed in the Soleidae – see respective entry.) If there is a true plesiomorphic character in the fishes of this group it is probably the symmetrical nature of the nasal organ (and possibly the olfactory laminae in Oncopterus and Psammodiscus). Specialized characters are the commencement of 66 a c b Fig. 48: Colistium nudipinnis (WAITE 1911) – 15 × the dorsal fin in advance of the nostrils of the blind side, the small narrowly placed eyes, the strongly asymmetrical nature of mouth and dentition, the toothless vomer, the fusion of the pelvic fin of the ocular side with the anal fin (in Ammotretis and Colistium) and the enlargement of the number of gill rakers (in Colistium). Otolith analysis indicates that the Rhombosoleinae as understood by NORMAN (1934) do not form a homogenous unit in a phylogenetic sense. The five genera of the Ammotretis Group instead seem to form a more natural unit to be separated not only from the other genera of the so-called Rhombosoleinae but perhaps from the Pleuronectidae altogether. In my opinion this group is of pre-pleuronectid origin, split off early from the main stem of the Pleuronectoidei probably at about the Citharid level in LAUDER & LIEM’s (1984) cladogram. Their degree of specialization in particular in respect to the fish-morphology would then be regarded as autapomorphic excluding them from a close relationship with other plesiomorphic groups such as Psettodidae, Citharidae, Tephrinectes or Paralichthodes. Based on otolith analysis I would recommend to establish a separate and new pleuronectoid family for the five genera of the Ammotretis Group. Colistium NORMAN 1926 Type-species: Ammotretis nudipinnis WAITE 1911 Diagnosis: Moderately thickset and not very elongate otoliths; ventral rim rather flat, dorsal rim with broad mid- to postdorsal angle, posterior tip blunt, rostrum short, massive, with inframedian position; index l:h 1.4 to 1.6. Otolith size up to 4 mm. Ostium slightly widened, anteriorly open, somewhat deepened, usually shorter than cauda. Cauda longer, narrower anteriorly but widened posteriorly, somewhat deepened, with rounded and very slightly inclined posterior tip. Index ol:cl quite variable, 0.75 to 1.3. Dorsal and ventral depression not connected around caudal tip, not forming a circumsulcal depression. Ventral depression indistinct, dorsal depression barely visible. This results in a relatively smooth inner face, except for the depressed sulcus. Inner face convex; outer face slightly concave, with some irregular ornamentation. Rims moderately sharp, irregularly crenulated and undulating. Measurements: nudipinnis guentheri l:h h:t 1.50 about 3 1.45-1.55 3.0-3.5 ol:cl 0.75 1.0-1.3 oh:ch con.i nm about 3.5 1.1-1.5 about 3.5 Discussion: Otoliths of Colistium differ from those of Ammotretis and Oncopterus in the rounded somewhat widened caudal tip and the somewhat larger size that they can reach (3 to 4 mm). In this respect their otolith pattern looks more “primitive” than that of the other two genera. The characters of the fishes, however, suggest Colistium to be the most apomorphic genus in this group. Side dimorphism: See entry to C. guentheri. Species and distribution: Two recent species both endemic to New Zealand – C. nudipinnis and C. guentheri. Schwarzhans: Pleuronectiformes 67 50 49a 49b 51a 49c 51c 51b Figs. 49-51: Colistium guentheri (HUTTON 1873) – 15 × Colistium nudipinnis (WAITE 1911) Fig. 48 Colistium guentheri (HUTTON 1873) Figs. 49-51 Investigated otoliths: One otolith (right side) from New Zealand, AUG-V 290 (pars; coll. Grenfell). Investigated otoliths: 3 otoliths, 2 (left and right side, figs. 49-50) off Wellington, BMNH 1923.11.5.5, one otolith (right side, fig. 51), AUGV 294 (coll. Grenfell). Discussion: The single otolith available from C. nudipinnis can readily be distinguished from those of C. guentheri by the following characters: the massive postdorsal angle, the considerably widened and deepened caudal tip and the close approach of the caudal tip of the sulcus towards the posterior tip of the otolith. The latter character is unique amongst Pleuronectiform otoliths resulting in a very unusual flatfish otolith morphology. Distribution: The species is endemic to New Zealand. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: Of the two otoliths obtained from the left and right side of one fish specimen the right handed otolith shows a more distinct and broad excisura. The additional otolith, however, which is also right handed, does not show an excisura at all. Ontogeny and variability: The two right handed otoliths available differ from each other in the development of the excisura, the proportion of ostium length to cauda length and the expression of the dorsal rim. 68 52a 53a 53c 52c 53b 52b 55 54 Figs. 52-55: Ammotretis rostratus GÜNTHER 1862 – 15 × Discussion: C. guentheri differs from C. nudipinnis in the less prominent medio- to postdorsal angle, the more regularly narrowed cauda which terminates at some distance from the posterior tip of the cauda, and the proportionally somewhat longer ostium. Distribution: This species is endemic to New Zealand. Ammotretis GÜNTHER 1862 Type-species: Ammotretis rostratus GÜNTHER 1862 Ostium somewhat widened, anteriorly open, somewhat deepened, slightly longer than cauda. Cauda narrower than ostium, slightly widened in the middle and with a tapering and pointed tip. Dorsal and ventral depression not connected around caudal tip, not forming a circumsulcal depression. Ventral depression short, feeble, dorsal depression also weak. Inner face slightly convex; outer face slightly concave to flat, rather smooth. Rims smooth, except for ventral rim which may be slightly undulated. Measurements: l:h h:t ol:cl 1.40-1.45 3.2-3.5 1.15-1.30 1.45 nm 1.2 1.10 3.1 1.0 syn. Tapirisolea RAMSAY 1883 (type-species: N.N.) rostratus tudori elongatus Diagnosis: Thin, very small, compressed otoliths, almost rectangular to irregularly rounded in outline; ventral and dorsal rim rather flat, the latter often with postdorsal angle, posterior tip blunt sometimes rounded, anterior rim blunt too, rostrum moderately strong or reduced in size, excisura and antirostrum relatively well developed; index l:h 1.1-1.5. Otolith size may not exceed 3 mm. Side dimorphism: Not apparent. oh:ch 1.2-1.5 1.25 1.2 con.i about 3 nm 3.5 Discussion: Ammotretis otoliths no doubt resemble those of Colistium. They are, however, more compressed with a more reduced rostrum and exhibit a different type of caudal tip. In these two respects Oncopterus resembles even better. Species and distribution: Four to five recent species, all from southern temperate Australia: Schwarzhans: Pleuronectiformes 69 a b c Fig. 57: Ammotretis elongatus McCULLOCH 1914 – 15 × Fig. 56: Ammotretis tudori McCULLOCH 1914 – 15 × A. rostratus, A. brevipinnis, A. tudori, A. macrolepis (possibly syn. A. tudori) and A. elongatus. Of these A. rostratus is the most widely distributed one. Ammotretis rostratus GÜNTHER 1862 Figs. 52-55 syn. syn. syn. syn. syn. Ammotretis rostratus vel adspersus KNER 1869 Rhombosolea bassensis CASTELNAU 1872 Solea uncinata KLUNZINGER 1880 Ammotretis zonatus MACLEAY 1883 Ammotretis ovalis SAVILLE-KENT 1889 Investigated otoliths: 4 otoliths, one (left side, fig. 52) from the coast of Victoria, Australia, off Melbourne, ZMH 20008, three (two left, fig. 53-54; one right, fig. 55) from off Hobart, Tasmania, ZMH Ot. 2.1.1995.1-2 (leg. BMNH 1934.3.18.1-10) and BMNH 1934.3.18.1-10. Variability: The otoliths of the three specimens investigated do not differ greatly from each other. One of the specimens (fig. 52) shows a more widened ostium than the others. Discussion: A. rostratus differs from A. tudori and A. elongatus in the more massive posterior tip of the otolith and the reduced rostrum. Distribution: Temperate Australia, from Port Jackson in New South Wales, Victoria, South Australia, southern Western Australia and Tasmania in shallow water. Ammotretis tudori McCULLOCH 1914 Fig. 56 Investigated otoliths: One otolith (left side) from off South Australia, BMNH 1925.3.20.1. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Similar to A. rostratus, but with a more prominent rostrum and a more rounded posterior tip. Distribution: Temperate Australia, in Victoria, South Australia and Tasmania. Ammotretis elongatus McCULLOCH 1914 Fig. 57 Investigated otoliths: One otolith (right side) from Kangaroo Isl., off South Australia, BMNH 1925.1.26.3. Discussion: Otolith extremely small in comparison to size of fish. Outline more rounded than in the other two species investigated and with a rather strong rostrum like A. rostratus. Distribution: Off South Australia. Oncopterus STEINDACHNER 1875 Type-species: Oncopterus darwini STEINDACHNER 1875 syn. Curioptera WHITLEY 1951 (unneeded substitute for Oncopterus) Diagnosis: Thin, compressed otoliths; ventral rim rather flat, dorsal rim gently curving with a prominent predorsal dome, posterior tip broadly rounded, anterior rim blunt; index l:h 1.1. Otoliths size may not exceed 2 mm. Ostium slightly wider than cauda, anteriorly open, somewhat deepened, shorter than cauda. Cauda slightly widened in the middle and with a tapering and pointed tip. Index ol:cl about 0.8. Dorsal and ventral depressions feeble not connected around caudal tip, not forming a circumsulcal depression. Inner face very slightly convex, almost flat; outer face flat, smooth. Rims sharp, smooth. 70 Measurements: darwini l:h 1.1 h:t about 3.5 ol:cl 0.8 oh:ch about 1.0 con.i nm Side dimorphism: No data. Discussion: Otoliths of Oncopterus are extremely small in comparision to the size of the fish (ratio about 1:100). Otherwise they resemble well otoliths of Ammotretis, particularly in the outline of the cauda and the compressed appearance. b a Fig. 58: Oncopterus darwini STEINDACHNER 1875 –15 × Species and distribution: A single recent species – O. darwini – from the southeastern coast of South America. In the absence of otoliths to be investigated Psammodiscus is included in the Ammotretis Group following NORMAN (1934), who related it to Oncopterus. Oncopterus darwini STEINDACHNER 1875 Fig. 58 Species and distribution: The type specimens (and for a long time the only specimens) were lacking geographical coordinates. The recent reference by GLOERFELT-TARP & KAILOLA is from northern Western Australia, vicinity of Barrow Island. Investigated otoliths: One otolith (right side) from off Patagonia, South-East America, BMNH 1930.9.4.21-22. Remarks: Due to the small size and the fragile nature of the otolith the only otolith successfully extracted from the fish has been somewhat damaged. The rostral portion of the otolith broke away when touched with the tweezers. However, it is quite apparent that the missing rostrum must have been a very short and blunt one. Taratretis LAST 1978 Type-species: Taratretis derwentensis LAST 1978 Distribution: This species is exclusively known from the southeastern coast of South America, from Rio Grande do Sul (southernmost Brazil) to San Matias Bay (Argentina). 7.3 Citharidae Remarks: Taratretis is a monospecific genus endemic to the shores of Tasmania (Australia). Otoliths have not been available for investigation. Psammodiscus GÜNTHER 1862 Type-species: Psammodiscus ocellatus GÜNTHER 1862 Genera: As understood here, I have reduced the Citharidae to the Citharinae of HUBBS (1945) and included the recent genera Citharus, Paracitharus, Citharoides and the fossil otolith based genus Rhombocitharus. Another fossil otolith based genus – Citharopsettodes – was found to be a junior synonym of the living Paracitharus. Remarks: Psammodiscus is a monospecific genus. Until very recently only the four type specimens were known. They are kept in the BMNH and I opened two of them in order to extract otoliths. Unfortunately, they seem to be completely dissolved by formalin. In a report of fishes trawled of southern Indonesia and northwestern Australia GLOERFELT-TARP & KAILOLA (1984) additional reference is given (coll CSIRO), but I did not have the opportunity to investigate any of the new specimens. Definition and relationship: When HUBBS (1945) established the family Citharidae he discussed at length the relatively primitive nature of the genera he included, but also one character (position of the vent on the eyed side) which could be regarded as an autapomorphic character of the family. He included left eyed (Citharinae) and right eyed (Brachypleurinae) genera. Otoliths indicate instead that the two subfamilies may not be so closely related. Brachypleurinae (which show a number of specialized characSchwarzhans: Pleuronectiformes 71 ters; see respective entry) are here separated from the Citharidae and constitute a family by themselves. The remainder, the left eyed Citharidae, form a cohesive group in otolith morphology as well. Paralichthodes (see respective entry) is, perhaps, a case of a dextral flatfish whose otoliths do resemble those of the sinistral Citharidae. In a recent cladistic analysis CHAPLEAU (1993) also regarded the Citharidae as polyphyletic but placed the dividing line between Citharoides and Citharus. He suggested that the dextral Lepidoblepharon and the sinistral Citharoides form a trichotomy with all remaining pleuronectiforms, with the sinistral Citharus and the dextral Brachypleura being in the latter clade. Otolith analysis, however, clearly contradicts this alignment and in stead suggests that the dividing line should be between the left eyed and right eyed Citharidae (Citharidae and Brachypleuridae as presented here). Citharid otoliths again are characterized by a number of plesiomorphic characters. These are the sulcus proportions in which the ostium is shorter than the cauda or both are of about equal length, and the narrow cauda which is sometimes slightly inclined posteriorly. Also the ostium is open anteriorly. The circumsulcal depression is much better developed than in the Psettodidae and the “genera of uncertain relationship”, but still not completely connected around the tip of the cauda. In conclusion, otoliths of the Citharidae sensu stricto support HUBBS’ (1945) concept of the intermediate phylogenetic position of this group. The pattern is also perfectly in accordance with LAUDER & LIEM’s (1984) cladogram which shows Citharidae branching off after Psettodidae and before the main diversification in the Pleuronectoidei commenced. Their fossil abundance, particularly in the early Tertiary, further supports the antiquity of the family. three genera exhibit an antitropical distribution pattern: Citharus in the Mediterranean and the Northeast Atlantic (but as an exception also along the coasts of tropical West Africa), Paracitharus along the coasts of South and southern East Africa, and Citharoides from Japan and Korea. Citharus RÖSE 1793 Type-species: Pleuronectes linguatula LINNAEUS 1758 syn. Eucitharus GILL 1889 (type-species: Pleuronectes linguatula) syn. Chopinopsetta WHITLEY 1931 (type-species: Pleuronectes linguatula) Remarks: I have followed HUBBS’ (1945) remarks in accepting Citharus as a valid genus name. Diagnosis: Thin, moderately elongate otoliths; ventral rim deeply curving, deepest midventrally, dorsal rim usually with distinct mid- and postdorsal angles, posterior tip rounded, blunt, or with obtuse angle, anterior rim with short massive rostrum, but without excisura; index l:h 1.4 to 2.0. Otolith size up to 7 mm. Ostium slightly wider than cauda and usually shorter too, anteriorly open, rather shallow. Cauda narrow, usually straight, but sometimes just very faintly inclining towards the tip, reaching close to the posterior tip of the otolith. Dorsal and ventral depressions well developed and large, but not completely connected around caudal tip to form a circumsulcal depression. Inner face almost flat; outer face flat to slightly concave, smooth to slightly ornamented. Rims sharp, often crenulated or irregularly undulating. Measurements: l:h h:t ol:cl oh:ch con.i 1.55-1.95 3.0 0.60-0.65 1.50-1.55 5.5 1.50-1.70 3.0-3.5 0.75-0.90 1.45-1.65 about 6 1.45-1.55 3.0-3.5 0.65-0.75 1.30-1.45 4-5 1.55-1.75 about 4 0.75-0.95 1.35-1.65 about 5 1.40-1.50 0.75 1.70 1.60-1.65 <3.0 0.65 1.70-2.00 about 5 Ontogeny: Citharid otoliths may reach up to 10 mm in length, but rarely exceed 7 mm. Since ontogenetic changes are generally slight, otoliths of 4 to 5 mm length are usually adequate for specific identification, but in some of the smaller fossil species otoliths of just 3 mm can be sufficient in size. linguatula (ad.) linguatula (juv.) †balearicus †lusitanicus sp.(STEUR.) †schuberti Distribution: The present distribution of citharids is somewhat patchy, clearly the relict of a once much wider distribution. Furthermore, all Discussion: Otoliths of Citharus do not differ much from those of the two other recent genera of the family – Paracitharus and Citharoides. As it Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: Not apparent. 72 seems the outline of Citharus otoliths usually is more angular, particularly the dorsal rim. In Paracitharus the ostium is nearly of the length of the cauda. Citharoides otoliths are more elongate than the other two and exhibit a more gently curving outline. Species and distribution: One recent species: C. linguatula known from the Mediterranean and the eastern Atlantic from Portugal to Angola. In addition there are 4 nominal fossil species described from European and North African sediments: C. balearicus from the Pliocene of Mallorca (Spain), SW-France and NW- Morocco, C. lusitanicus from the Lower and Middle Miocene of Portugal, France, Austria and Poland (both Paratethys), C. schuberti from the Upper Miocene and Lower Pliocene of Italy. C. miocenicus from the Lower Miocene of Germany was based on a single non-diagnostic juvenile specimen and must therefore be regarded as of doubtful nature. However, STEURBAUT (1984) figured a Citharus sp. from the Lower Oligocene to Middle Miocene of France, which in fact may very well represent a fourth species. I agree with STEURBAUT to leave this species in open nomenclature until more material becomes available from the North Sea Basin and the taxonomical status of C. miocenicus becomes resolved. The definition and delimitation of some of the fossil species is not as yet sufficiently validitated (see respective entries). Citharus linguatula (LINNAEUS 1758) Figs. 59-64 syn. Pleuronectes macrolepidotus BLOCH 1787 syn. Pleuronectes citharus SPINOLA 1807 syn. Pleuronectes patarachia NARDO 1847 Investigated otoliths: 6 otoliths, 2 (left and right side, figs. 62-63) and 1 (right side, fig. 64) from off Neapel, ZMH 19951, 3 (right side, figs. 59-61) from off Angola, ZMH Ot. 2.1.1995.3-4 (leg. BMNH 1930.5.6.27-29) and BMNH 1930.5.6.27-29. Remarks: I have followed NORMAN’s view in accepting linguatula as valid species name. This also rules out possible confusion with Citharoides macrolepidotus HUBBS 1915. Ontogeny and variability: The 6 otoliths investigated are from two different sizes. Three are of relatively small size (about 4 mm, figs. 62-64) and have not developed all pertinent diagnostic features, whereas the other three are more than 6 mm (figs. 59-61) long and are typical adult specimens. A larger set of recent otoliths is figured by CHAINE (1936) of sizes up to 7 mm. Larger otoliths (more than 5 mm of length) are slightly more elongate, lack the fine crenulation of the rims, and have developed the postdorsal portion more strongly, whereas the middorsal portion is more flat. Variability is not very prominent and restricted to minor variations of the proportions and in the expression of the dorsal rim. Discussion: The differentiation of C. linguatula from the various nominal fossil species is by no means clear. It seems that, except for C. schuberti, the fossil species in question have achieved a mature state of the morphological pattern at smaller sizes. NOLF (1985) has tentatively synonymized C. balearicus with the recent species. From my investigations, however, it seems that otoliths of C. balearicus (and C. sp. too) regularly are somewhat more compressed than those of C. linguatula. C. lusitanicus exhibits similar proportions than C. linguatula but has a more pronounced mediodorsal angle and seems also slightly more thinset. C. schuberti finally resembles the recent species both in proportions and outline except for its very characteristic vertically cut posterior rim, and in its being more thickset. More material of C. balearicus and C. lusitanicus will be needed before the validity of these two species can be proven in comparison with the recent C. linguatula. Distribution: Mediterranean and eastern Atlantic from Portugal to Angola on the continental shelf. Citharus lusitanicus JONET 1972 Figs. 65-73 syn. Eucitharus rhenanus KOKEN – WEINFURTER 1952: pl. 2, figs. 9-10 syn. Eucitharus lusitanicus JONET 1972 – JONET 1972: fig. 12; pl. 4, figs. 131-133 syn. Citharus lusitanicus – SMIGIELSKA 1979: figs. 34-35; pl. 8, figs. 6-8 Schwarzhans: Pleuronectiformes 73 59a 60 59b 62c 61 62a 62b 64a 63 64b Figs. 59-64: Citharus linguatula (LINNAEUS 1758) – 10 × syn. Eucitharus lusitanicus – JONET 1980: pl. 4, fig. 3 syn. Citharus lusitanicus – STEURBAUT & JONET 1982: pl. 4, figs. 14-16 ?syn. Citharus lusitanicus – STEURBAUT 1984: pl. 34, figs. 11-16 syn. Citharus lusitanicus – RADWANSKA 1992: fig. 151; pl.35, figs. 3-6 ?syn. Citharus sp.1 – RADWANSKA 1992: fig. 152; pl. 36, figs. 14-16 Piscium Catalogus, Part Otolithi piscium, Vol. 2 syn. Citharus sp.2 – RADWANSKA 1992: fig. 153; pl. 36, figs. 1-2 Investigated otoliths: 97 otoliths, 9 (figs. 65-67) from Costa da Caparica, Portugal, Burdigalian, Lower Miocene (topo- and strati-typical), coll. Schwarzhans, 88 (figs. 68-72) from Korytnica, Poland, Badenian, Middle Miocene, ZPalUW-RaK 408-417 (coll. Radwanska). 74 65 67a 66a 67b 66b 68a 70 69 68b 72 71 Figs. 65-72: Citharus lusitanicus JONET 1972 – 10 × Ontogeny and variability: Two otoliths figured are 3.5 mm (fig. 65) and 4 mm (fig. 66) long. They seem to have developed all pertinent diagnostic features indicating that otoliths of this species mature at smaller sizes than those of the recent C. linguatula. The largest specimen known so far is JONET’s type of slightly over 5 mm of length. The smallest specimen known to me (fig. 67) is a b Fig. 73: Citharus aff. lusitanicus JONET 1972 – 10 × 3 mm long and shows the kind of marginal crenulation typical for juvenile Citharus otoliths (see C. linguatula). – The otoliths described from the Middle Miocene of Poland by RADWANSKA (1992) (see also figs. 68-72) perfectly fit with the specimens from the Middle Miocene of Portugal. A specimen originally described as Citharus sp.1 by RADWANSKA is considerably more compressed, thus resembling STEURBAUT’s Citharus sp. from the Oligocene and Miocene of France. Since the specimen from Poland is an unique finding it could also represent a teratological effect. I have therefore selected to regard it as C. aff. lusitanicus (fig. 73). Two other otoliths from Poland – described as Citharus sp.2 by RADWANSKA (1992) – in my opinion just represent eroded specimens of C. lusitanicus (not figured). Discussion: C. lusitanicus very closely resembles the recent C. linguatula and the Pliocene C. balearicus (see respective entries for discussion). Schwarzhans: Pleuronectiformes 75 75 74a 74c 74b 76 Figs. 74-76: Citharus balearicus BAUZA RULLAN 1955 – 10 × Distribution: Lower to Middle Miocene of Portugal, France (Aquitaine Basin), Austria and Poland (Paratethys). Citharus balearicus BAUZA RULLAN 1955 Figs. 74-76 syn. Eucitharus balearicus BAUZA RULLAN 1955 – BAUZA RULLAN 1955: pl. 8, fig. 16 syn. Eucitharus balearicus – BAUZA RULLAN 1964: pl. 4, fig. 5 syn. Eucitharus balearicus – BAUZA RULLAN 1972: fig. 17 syn. Citharus linguatulus (LINNAEUS) – NOLF & CAPPETTA 1988: pl. 18, fig. 14 Investigated otoliths: 5 otoliths (figs. 74-76) from the river banks of the Oued Beth near Dar Bel Hamri, NW-Morocco, Sands of Dar Bel Hamri, Lower Pliocene, coll. Schwarzhans. Ontogeny and variability: The otoliths investigated are between 3.5 and 4.5 mm in length. They do not exhibit any significant ontogenetic changes or variability. Their relatively smooth outline indicates a mature ontogenetic stage of the otolith morphology. Discussion: NOLF (1985) has synonymized C. balearicus with the recent C. linguatula. In my opinion, however, the fossil specimens are always more compressed than recent ones of the same Piscium Catalogus, Part Otolithi piscium, Vol. 2 ontogenetic stage. I therefore provisionally keep C. balearicus as a valid species. Differentiation from C. lusitanicus and C. sp. (sensu STEURBAUT, 1984) both from the Miocene is much less obvious. C. lusitanicus mainly differs in being more elongate, but there are indications that intermediate forms may exist. Differentiation of the two species will then become very difficult if at all possible. C. sp. (sensu STEURBAUT) is just slightly more compressed and shows a more regularly rounded outline. Distribution: Lower Pliocene of SW-France and NW-Morocco and Upper Pliocene of Mallorca (Spain). Citharus sp. (sensu STEURBAUT 1984) ?ref. Eucitharus miocenicus WEILER 1942 – WEILER 1942: pl. 4, fig. 36 ref. Citharus miocenicus – STEURBAUT 1979: pl. 11, fig. 16 ?ref. Citharus miocenicus – NOLF & SMITH 1983: pl. 2, fig. 21 ref. Citharus sp. – STEURBAUT 1984: pl. 34, figs. 3-9 Remarks: WEILER’s original description was based on a juvenile not diagnostic otolith of only 2 mm of length. NOLF & SMITH (1983) figured another specimen from the Lower Miocene of the North Sea Basin (Belgium), which is slightly larg- 76 c a b Fig. 77: Citharus schuberti BASSOLI 1906 – 10 × er (2.5 mm), but still does not exhibit all necessary diagnostic features. Besides the two small specimens STEURBAUT (1984) has figured otoliths of up to 4 mm in length. Although originating from different basins (Aquitaine Basin) they could possibly represent the same species as the specimens from the North Sea Basin. However, until more material becomes available from the North Sea Tertiary it seems advisable to follow STEURBAUT’s recommendation to leave these otoliths in open nomenclature. Ontogeny and variability: Otoliths of C. sp. seem to have reached morphological maturity at relatively small sizes of about 3 mm. However, even larger specimen of up to 4 mm occasionally exhibit some fine marginal crenulation. The type specimen of C. miocenicus was only 2 mm in length and is not diagnostic in its outline. It must be considered as a juvenile. Variability is limited to details of the outline, ornamentation and slight variations of the length to height ratio. Discussion: C. sp. (sensu STEURBAUT 1984) as defined here is very similar to C. balearicus from the Pliocene of the Mediterranean. Major difference is only the more regularly rounded outline observed in C. sp. However, more and larger specimens of both species are needed to validate the diagnostic value of this character. Distribution: Lower Oligocene to Lower Miocene of France (Aquitaine Basin) and possibly also Lower Miocene of the North Sea Basin (Germany and Belgium). Citharus schuberti BASSOLI 1906 Fig. 77 syn. Citharus schuberti BASSOLI 1906 – BASSOLI 1906: pl. 6, fig. 9 syn. Eucitharus schuberti – ANFOSSI & MOSNA 1979: pl. 4, fig. 10 syn. Citharus schuberti – NOLF & STEURBAUT 1983: pl. 7, fig. 25 Investigated otoliths: BASSOLI’s type-specimen from Montegibbio, Italy, Tortonian, Upper Miocene, IPUM 16629. Discussion: Although only few specimens so far have been recorded they are nevertheless easily recognized by their flat dorsal rim, the vertically cut posterior rim and the more thickset nature. Otherwise, in outline and proportions, they resemble closest the recent C. linguatula. Distribution: Known from the type-specimen from the Upper Miocene of Italy and few additional specimens from the Lower Pliocene of Italy. All records so far are from relatively deep marine environments. C. schuberti does not seem to occur simultaneously with C. balearicus although found in the same general area and stratigraphic sequence. Possibly, C. schuberti represents a deeper water species and C. balearicus its shallow water equivalent. C. schuberti is one of the few fossil Pleuronectiform species collected from deeper marine environments. Schwarzhans: Pleuronectiformes 77 Paracitharus REGAN 1920 Type-species: Arnoglossus macrolepis GILCHRIST 1905 1939.5.24.1706-1717), 2 BMNH 1939.5.24.17061717, 1 otolith (right side, fig. 83) from off South Africa, ZMH Ot. 3.1.1994.11 (leg. ZMUC). syn. Citharopsettodes SCHWARZHANS 1978 (type-species: Citharopsettodes angustus SCHWARZHANS 1978) Ontogeny and variability: From this species I have available a continuous set of otoliths of variable sizes from about 2.5 mm to 7 mm in length. The smallest otoliths up to 2.5 mm (figs. 86-87) exhibit a fairly generalized pattern which is even difficult to distinguish from Citharus species (only valuable difference might be the proportions of ostium to cauda). They are compressed (ratio l:h 1.35) and show undulated margins. Their outline is pretty rounded. Otoliths from 3.5 to 5.5 mm (figs. 79-85) are still similar as far as marginal crenulation is concerned. Ratio l:h ranges from 1.35 to 1.45. The outline is still very much rounded, but the postdorsal portion becomes a little more accentuated. The only large otolith available (7 mm, fig. 78) is considerably more elongate (ratio l:h 1.6) and exhibits a completely smooth outline. Its posterior tip is somewhat pointed. – It seems that diagnostic valid characters are only developed in otoliths of about 6 mm or more. Diagnosis: Moderately thin, roundish to moderately elongate otoliths; ventral rim deeply curving, deepest midventrally, dorsal rim usually with distinct pre- and postdorsal angles, posterior tip rounded or angular, anterior rim with short massive rostrum, but without excisura; index l:h in adults 1.5 to 2.0. Otolith size up to 7 mm. Ostium very slightly wider than cauda and of about equal length. Cauda narrow, usually straight, but sometimes just very faintly inclining towards the tip, reaching close to the posterior tip of the otolith. Dorsal and ventral depressions well developed and large, but not completely connected around caudal tip to form a circumsulcal depression. Inner face almost flat; outer face flat to slightly concave, smooth to slightly ornamented. Rims sharp, smooth in adults, crenulated or irregularly undulating in smaller specimens. Measurements: l:h h:t ol:cl macrolepis (ad.) 1.60 about 2.5 1.0-1.1 macrolepis (juv.) 1.35-1.45 about 3 †angustus 2.00 about 3 0.9 oh:ch 1.4-1.5 con.i about 5 1.15 about 6 Side dimorphism: Not apparent. Discussion: Otoliths of Paracitharus very closely resemble those of Citharus. Main differences are the proportions of the sulcus. From the point of otolith morphology alone this may not warrant separation in two genera. Species and distribution: One recent species – P. macrolepis – from South and SE-Africa (Natal to Kenya) and one fossil species – P. angustus – from the Lower Pliocene of Italy. Paracitharus macrolepis (GILCHRIST 1905) Figs. 78-87 Investigated otoliths: 13 otoliths, figured otoliths 10 (left and right side, figs. 78-82, 84-87) from off Zanzibar, ZMH Ot. 3.1.1994.1-10 (leg. BMNH Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: See entry to genus and to P. angustus. Distribution: Southern Africa, from Natal to Kenya in moderately deep water (100 to 200 m). Paracitharus angustus (SCHWARZHANS 1978) Fig. 88 syn. Citharopsettodes angustus SCHWARZHANS 1978 – SCHWARZHANS 1978: pl. 10, fig. 123 Investigated otoliths: One otolith (the unique type-specimen) from Cetona near Siena, Toscana, Italy, Zanclian, Lower Pliocene, SMF P 5696. Discussion: The single specimen known to date is a well preserved large otolith of about 7 mm of length. In ignorance of recent otoliths of Paracitharus I had originally placed this species in a (assumed) fossil genus of its own – Citharopsettodes – and regarded it as a Psettodidae intermediate in morphology between that family and the Citharidae. Now, that otoliths of the recent Paracitharus are available it becomes apparent that 78 78a 78c 78b 79 80 82a 81 82b Figs. 78-82: Paracitharus macrolepis (GILCHRIST 1905) – 10 × P. angustus should belong to the same genus. General appearance and proportions of the sulcus are practically identical. However, the fossil P. angustus is considerably more elongate and also shows a comparatively narrow ostium making specific separation indubitable. The occurrence of the genus Paracitharus in the Pliocene of the Mediterranean indicates that this genus once was more widely distributed, and that its present distribution represents a secondary endemism. Schwarzhans: Pleuronectiformes 79 84 85 83 87 86 Figs. 83-87: Paracitharus macrolepis (GILCHRIST 1905) – 10 × Distribution: Only known from the type-specimen from the Lower Pliocene of Italy. Sedimentary environment is deeper marine, off the continental shelf. Citharoides HUBBS 1915 Type-species: Citharoides macrolepidotus HUBBS 1915 syn. Brachypleurops FOWLER 1934 (type-species: Brachypleurops axillaris = Citharoides macrolepidotus) Diagnosis: Thin, elongate otoliths; ventral rim gently curving, deepest midventrally, dorsal rim shallow, without distinct pre- and postdorsal angles, posterior tip rounded, anterior rim with short massive rostrum, but without excisura; index l:h about 2.0. Otolith size reaching at least 6.5 mm. Sulcus narrow. Ostium almost as wide as cau- da and also about as long. Cauda narrow, almost straight, very faintly inclining towards the tip, reaching close to the posterior tip of the otolith. Dorsal and ventral depressions well developed and large, but not completely connected around caudal tip to form a circumsulcal depression. Inner face relatively flat; outer face flat to slightly concave, smooth. Rims moderately sharp, smooth somewhat undulating posterior-ventrally. Measurements: macrolepidotus l:h 2.05 h:t <3.0 ol:cl about 1.0 oh:ch 1.35 con.i about 5 Side dimorphism: No data. Discussion: Similar to Citharus and Paracitharus but more elongate, with a smooth dorsal rim, and a narrow sulcus with ostium and cauda of about equal length. Species and distribution: One recent species off Japan and Korea. Citharoides macrolepidotus HUBBS 1915 Fig. 89 syn. Brachypleurops axillaris FOWLER 1934 Investigated otoliths: One otolith (right side) from off Kochi, Japan, ZMH Ot. 2.1.1994.12 (leg. Sasaki). Fig. 88: Paracitharus angustus (SCHWARZHANS 1978) – 10 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Off Japan and Korea. 80 a c b Fig. 89: Citharoides macrolepidotus HUBBS 1915 – 10 × †Rhombocitharus SCHWARZHANS 1994 Type-species: Rhombus rhenanus KOKEN 1891 Diagnosis: Thin, compressed to moderately elongate otoliths; ventral rim deeply curving, deepest midventrally, dorsal rim usually shallow, with indistinct predorsal angle and pronounced postdorsal portion, posterior tip rounded, sometimes obtuse angular, anterior rim with very short indistinct rostrum, and without excisura; index l:h 1.15 to 1.8. Otoliths small, merely reaching 4 mm. Ostium about as wide as cauda, about the same in length or slightly shorter, anteriorly indistinctly opened, rather shallow. Cauda narrow, straight, sometimes tapering, reaching moderately close to the posterior tip of the otolith. Dorsal and ventral depressions well developed and large, incompletely connected around caudal tip to form a circumsulcal depression. Inner face almost flat; outer face flat to slightly concave, smooth to slightly ornamented. Rims sharp, sometimes crenulated or irregularly undulating but mostly smooth. Measurements (ab. = about): l:h †biaculeatus 1.55-1.75 †cauneillensis 1.30-1.40 †circularis 1.35-1.40 †rhenanus (ad.) 1.55-1.80 †rhenanus (juv.) 1.40-1.55 †rhomboides 1.20 †novaezeelandiae 1.85 h:t ab. 3.0 ab. 2.0 ab. 3.0 ab. 2.5 ol:cl oh:ch ab. 1.0 1.0-1.1 ab. 1.0 ab. 1.0 0.8-0.9 1.0-1.1 1.15-1.25 1.05-1.2 1.3-1.7 ab. 1.0 ab. 1.0 1.2 1.3 con.i ab. 4.5 ab. 4.0 Side dimorphism: Not apparent. Discussion: Most Rhombocitharus species described so far have been based on otoliths of less than 2.5 mm of length. In fact, the only species of which larger specimens are known (up to 4 mm) is R. rhenanus. Analysis of a good ontogenetic sequence of otoliths of this species have shown that only otoliths of 3 mm of length or more have developed the full set of diagnostic valid features. Principal ontogenetic changes concern the ratio l:h as can be seen from above listing. Therefore, it must be concluded that the other four species are based on juveniles. It is true, however, that even those juveniles can be distinguished sufficiently from each other to warrant valid diagnoses, but one must expect that these will change once larger otoliths become available. For the time being the four species in question are (tentatively) regarded as valid, but it is strongly recommended that future descriptions of new species should be based on otoliths of at least 3 mm in length. Otoliths of Rhombocitharus in many ways are morphologically intermediate between Citharidae and Scophthalmidae. Many characters such as outline, general habitus and proportion of ostium to cauda length resemble citharids. The narrow ostium which is about the height of the cauda and the nearly complete circumsulcal depression on the other hand resemble Scophthalmidae and also certain Bothidae. In particular right handed otoliths of the Scophthalmid genus Lepidorhombus are quite similar. Also in Scophthalmidae the ostium usually is only slightly longer than the cauda (whereas in bothids it is usually about 1.5 to 2 times as long). In conclusion, features regarded as plesiomorphic resemble citharids, whereas features assumed to be apomorphic resemble Scophthalmidae. Therefore, an alternative systematic position for Rhombocitharus would be to regard it as the most plesiomorphic member in Scophthalmidae. Schwarzhans: Pleuronectiformes 81 91 90a 92 90b 94 95 93a 93b 96c 96a 96b 97 98 Figs. 90-98: Rhombocitharus rhenanus (KOKEN 1891) – figs. 90-97 = 15 ×, fig. 98 = 25 × Species and distribution: Rhombocitharus contains 6 nominally valid fossil species – R. circularis from the Lower Eocene of England and France, R. biaculeatus from the Middle Eocene of Belgium and England, R. cauneillensis from the Upper Eocene of France (Aquitaine Basin), R. rhomboides from the Lower Oligocene of northern Germany and Belgium (North Sea Basin), and R. rhenanus from the Middle and Upper Oligocene of northern Germany, Belgium and the Netherlands (North Sea Basin) and from the Middle Oligocene of the Mainz Basin in Germany. Genus aff. R. novaezeelandiae from the Lower Miocene of New Piscium Catalogus, Part Otolithi piscium, Vol. 2 Zealand is only tentatively included in this genus and might very well represent a fossil genus of its own. Rhombocitharus rhenanus (KOKEN 1891) Figs. 90-98 syn. Rhombus rhenanus KOKEN 1891 – KOKEN 1891: pl. 5, fig. 12 syn. Solea guestfalicus KOKEN 1891 – KOKEN 1891: pl. 5, fig. 10 82 syn. Eucitharus rhenanus – POSTHUMUS 1923: figs. 52-53 syn. ?Eucitharus rhenanus – WEILER 1942: pl. 4, fig. 37; pl. 5, figs. 2-3 syn. Solea aff. guestfalica – WEILER 1958: pl. 3, figs. 30-31 syn. ?Eucitharus rhenanus – ZILCH 1965: pl. 37, fig. 22 syn. Solea guestfalica – ZILCH 1965: pl. 37, fig. 23 syn. Eucitharus belgicus GAEMERS 1972 – GAEMERS 1972: pl. 1, fig. 2; pl. 3, figs. 5-6 ?syn. Sebastes weileri GAEMERS 1972 – GAEMERS 1972: pl. 1, fig. 5; pl. 3, fig. 4 syn. Bothidarum weileri SCHWARZHANS 1974 – SCHWARZHANS 1974: figs. 60-61; pl. 3, fig. 13 syn. Soleidarum guestfalica – SCHWARZHANS 1974: figs. 58-59; pl. 3, fig. 16 syn. Bothidarum weileri – SCHWARZHANS 1973: pl. 1, fig. 6 syn. Bothidarum weileri – MENZEL 1980: pl. 2, fig. 7 syn. Bothidarum weileri – MENZEL 1983: pl. 4, fig. 7 ?syn. Scophthalmidarum sp. – MENZEL 1983: pl.1, fig. 6 syn. Citharus belgicus – GAEMERS 1984: pl. 4, figs. 13-14 syn. Citharus sp. – MÜLLER 1994: pl. 10, figs. 8-9 syn. Rhombocitharus rhenanus – SCHWARZHANS 1994: figs. 498-506 Investigated otoliths: The lectotype (SMF P 1133a, fig. 90) and two paralectotypes (SMF P 1132, figs. 91-92) of R. rhenanus from Waldböckelheim, Mainz Basin, Germany, Middle Oligocene, the neotype of Solea guestfalicus (SMF P 1425, fig. 98) from Bünde, northern Germany, Upper Oligocene, and the holotype of Bothidarum weileri (SMF P 4279, fig. 96) from Moers-Schwafheim, northern Germany, Upper Oligocene. In addition I have investigated some 75 otoliths from various localities in northern Germany of Upper Oligocene age; figured specimens are from Söllingen (otolith investigated by KOKEN and identified as Percidarum varians, PMHUB Ot. 147, fig. 93), and 3 otoliths from Ratingen near Düsseldorf (coll. Schwarzhans, leg. Klinger and Boscheinen, figs. 94, 95, 97). Fig. 99: Rhombocitharus rhomboides (SCHWARZHANS 1973) – 10 × Remarks: R. rhenanus has also frequently been described from locations outside the North Sea Basin and from quite different stratigraphic levels. All these secondary records represent different species. The records from the Miocene of the Paratethys (Austria) represent either Lepidorhombus subtriangularis (in the sense of SCHUBERT, 1906) or Citharus lusitanicus (in the sense of WEINFURTER, 1952). A record from the Upper Cretaceous of Austria by LIEBUS (1927) does not represent a Pleuronectiform at all but likely a perciform (SCHWARZHANS 1997). Ontogeny and variability: For discussion of ontogenetic changes see chapter discussion to the genus. Variability in this species is moderate. But together with the drastic ontogenetic changes this apparently had led in the past to the erection of so many different species which now have to be placed in synonymy. Major variations are seen in the development of the posterior and postdorsal rims, and the length-proportions of ostium and cauda, both particularly so in juveniles. In some instances ventral and posterior rims are somewhat undulated. Discussion: Otoliths of R. rhenanus are more elongate than those of R. rhomboides of the same size. It differs from all other species known so far in the ostium being always somewhat longer than the cauda. It must reminded, however, the comparison with other species of the genus is solely based on juveniles. R. rhenanus is the only species from which adults are known for certain. Distribution: Middle and Upper Oligocene of the North Sea Basin (northern Germany, Belgium and the Netherlands) and Middle Oligocene of the Mainz Basin (Germany). Schwarzhans: Pleuronectiformes 83 100a 100b 101 Figs. 100-101: Rhombocitharus ccauneillensis (NOLF 1988) – 25 × Rhombocitharus rhomboides (SCHWARZHANS 1973) Fig. 99 syn. Bothidarum rhomboides SCHWARZHANS 1973 – SCHWARZHANS 1973: pl. 1, fig. 5 syn. Citharus belgicus GAEMERS – NOLF 1976: pl. 17, figs. 17-18 syn. Bothidarum rhomboides – SCHWARZHANS 1977: fig. 29 Investigated otoliths: The holotype (RGM 175647, fig. 99), 3 paratypes (1 coll. Schwarzhans, 2 coll. Schürmann) and one additional otolith (coll. Geol. Landesamt of NRW), all from the shaft Sophia Jacoba IV near Hückelhoven, northern Germany, depth interval 55-80 m, Lower Oligocene. Ontogeny and variability: Since the few otoliths investigated are very much of the same size analyses of ontogenetic changes and variability are not possible. Discussion: This species was based on rather juvenile otoliths in the order of 1.5 to 2.0 mm. They are easily recognized by their extremely compressed appearance and the rombohedral outline with its strong predorsal angle. Nevertheless, the validity of this species must be regarded as preliminary for the time being until larger specimens have come to light. There is indeed a good chance for such additional material since a newly sunk shaft at Hückelhoven has yielded a rich Lower Oligocene fauna. However, this material has not been picked and determined until now. Distribution: Lower Oligocene of northern Germany and Belgium. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Rhombocitharus cauneillensis NOLF 1988 Figs. 100-101 syn. Citharus cauneillensis NOLF 1988 – NOLF 1988: pl. 14, fig. 3-4 Investigated otoliths: 3 otoliths, the holotype (IRSNB P 4519, fig. 100) from Cauneille and the two paratypes (one figured, IRSNB P 4520, fig. 101) from Saint-Lon-les-Mines, all Upper Eocene of Aquitaine Basin (France). Discussion: The three unique type-specimens of this species are all very small, between 1.0 and 1.5 mm. They may not have developed all pertinent diagnostic features at this size. Also all of them are slightly eroded along the rims or on the inner face. Hence the taxonomic validity of the species at present is somewhat questionable. R. cauneillensis is very similar to R. circularis from the Lower Eocene of England (London Basin) and France (Aquitaine Basin). R. cauneillensis differs from the older species in the more undulating posterior rims and the relatively short cauda. Additional material has yet to prove, whether these delicate differences are statistically stable or not. Distribution: Upper Eocene of the Aquitaine Basin (France). genus aff. Rhombocitharus novaezeelandiae n.sp. Fig. 102 Name: After New Zealand, from where this species has been obtained. Holotype (and unique specimen): Fig. 102, NZGS. Type locality: Awamoa Creek, Otago, New Zealand South Island. 84 7.4 Brachypleuridae a b c d Fig. 102: genus aff. Rhombocitharus novaezeelandiae n.sp. – 15 × Age: Altonian, Lower Miocene. Diagnosis: Elongate otolith with shallow ventral and dorsal rims and pointed posterior tip. Inner face rather convex in vertical direction. Cauda narrower than ostium, not much shorter. Description: Outline: Otolith small, about 2 mm long and elongate. Dorsal and ventral rims shallow, dorsal rim with rounded pre- and postdorsal angles; anterior tip somewhat pointed, posterior tip more sharply pointed. Otolith rather thickset. Inner face: Moderately convex in horizontal direction and more strongly convex in vertical direction. Sulcus moderately long and wide, rather shallow. Ostium wider than cauda, but not much longer, with pseudoostial opening. Cauda straight, terminating at some distance from the posterior tip of the otolith. Colliculi well separated. Dorsal and ventral depressions shallow, not completely fused around the caudal tip. Other views: Rims moderately sharp to thickset, smooth. Outer face rather flat, smooth. Discussion: The genus Rhombocitharus so far has only been reported from the European Tertiary. This record from New Zealand is only tentatively placed into the genus and may very well represent yet another fossil genus of Citharidae. Outline and habitus of the otolith does show some remarkable differences to the European species. The single holotype is a rather small specimen and is probably from a subadult fish. Nevertheless, it is very characteristic and thus warrants the establishment of a new species. Genera: The family Brachypleuridae as defined here contains two genera – Brachypleura and Lepidoblepharon. Definition and relationship: When HUBBS (1945) erected the new family Citharidae he included the three left eyed genera Citharus, Citharoides and Paracitharus as Citharinae (see chapter 7.3 – Citharidae in this treatise) and the two right eyed genera Brachypleura and Lepidoblepharon as Brachypleurinae. The three former genera had been removed from the Bothidae and the two latter from the Pleuronectidae of NORMAN’s classification. In his detailed analysis of the above genera HUBBS discussed at length the primitive characters shared with Psettodidae (presence of a spine in the pelvic fin and wide separation of gill-membranes) and the various more derived characters shared with Bothidae and Pleuronectidae. He defined one character as exclusive to Citharidae s.l., that is the position of the vent on the eyed side. However, he also noted that Brachypleura (and possibly Lepidoblepharon as well) differ in several aspects from the left eyed genera. Otoliths of Brachypleura and Lepidoblepharon indeed strongly suggest that the two genera may not be as closely related to the Citharidae s.s. (Citharinae of HUBBS) as previously assumed. They are characterized by a number of unique features which distinguish them from the left eyed citharids: the strongly reduced sulcus opening, the good separation of ostium and cauda (at least in left sided otoliths) the latter being slightly shorter than the ostium but of about equal width and with a rounded tip. Otoliths of Brachypleura as the more advanced genus are additionally characterized by the ventral expansion of the collum (see chapter 6.1; incipient in Lepidoblepharon), the reduced rostrum and the presence of a strong predorsal lobe. In conclusion, it is my recommendation to remove Brachypleura and Lepidoblepharon from the Citharidae and place them in a family of their own. Lepidoblepharon is the more plesiomorphic in this family and its otolith outline bears some resemblance to citharids, indicating nevertheless some Schwarzhans: Pleuronectiformes 85 relationship of the two families. Relationship of the Brachypleuridae to “higher” flatfishes, however, remains obscure. Resemblance with certain Soleidae is probably superficial and due to convergent evolution. Also, the possible relationship with Pleuronectidae suggested by their dextral body-orientation and the reduced sulcus opening in otoliths does not seem very convincing (although Lepidoblepharon otoliths resemble those of the Poecilopsettinae to some degree). Most likely, Brachypleuridae represent a separate specialized offshot from the main pleuronectoid lineage at approximately the citharid to scophthalmid level in the cladogram of LAUDER & LIEM (1983). Ontogeny: Available otoliths range in size from 1.5 to 3.0 mm. Although the smallest specimens are more rounded in outline they already seem to have developed all important and diagnostically valid features. Distribution: Brachypleura is known from a single recent species in the Indo-West-Pacific (India, Indonesian Archipelago and Philippines), a fossil species from the Lower Oligocene of France and a second fossil species tentatively attributed to this genus from the Upper Eocene of Java, thus indicating the antiquity of the family and its two genera. The monospecific Lepidoblepharon is known from very few specimens from Indonesia, northern Australia and Japan. Lepidoblepharon WEBER 1913 Type-species: Lepidoblepharon ophthalmolepis WEBER 1913 Diagnosis: Moderately thickset, compressed otoliths, almost circular in shape except for the somewhat pointed anterior tip. Dorsal and ventral rims regularly curving, without prominent angles, anterior tip blunt, somewhat pointed at the rostrum, posterior tip broadly rounded; index l:h 1.15-1.2. Otolith size at least 3 mm. Sulcus shallow, short, anteriorly closed and posteriorly terminating at some distance from the posterior tip of the otolith. Ostium slightly longer than cauda, not wider. Cauda with a rounded termination. Colliculi well developed and separated (in left hand otoliths; nearly fused in right hand otoliths). Collum slightly enlarged ventrally. Dorsal and ventral depressions well developed, Piscium Catalogus, Part Otolithi piscium, Vol. 2 wide and deep but not completely fused behind cauda to form circumsulcal depression. Inner face relatively flat; outer face slightly convex, smooth. All rims rather sharp. Measurements: l:h ophthalmolepis (l) 1.20 ophthalmolepis (r) 1.15 h:t 3.5 ol:cl 1.25 1.55 oh:ch 1.0 con.o 3.2 Side dimorphism: Side dimorphism in this genus seems to be quite well developed. In left hand otoliths the sulcus is much wider than in right hand otoliths and the colliculi are well separated, whereas in right hand otoliths they are almost completely fused. Also right hand otoliths seem to be more compressed than left hand otoliths. Discussion: Of the two genera of the family Brachypleuridae, Lepidoblepharon no doubt is the one with the more plesiomorphic otolith pattern. This is most apparent in the outline of the otoliths with the lack of the predorsal projection and the somewhat pointed rostrum. In this respect Lepidoblepharon resembles Citharid otoliths. On the other hand the sulcus with its short cauda terminating at some distance from the posterior tip of the otolith and its ovale, rounded colliculum separates Lepidoblepharon from the Citharidae. This apomorphic character it shares with Brachypleura. Species and distribution: The single species L. ophthalmolepis has been caught very rarely in the Arafura Sea (Indonesia) in about 300 to 400 m depth and off Japan and northern Australia. A possible second species from off Queensland, Australia, kept in the AMS collection (AMS I.23999-003, as Lepidoblepharon? sp.) was also investigated but its otoliths were found to be dissolved by formalin. Lepidoblepharon ophthalmolepis WEBER 1913 Figs. 103-104 Investigated otoliths: 2 otoliths (left and right side), 200 km NW of Port Hedland, West Australia, from 400 m depth, AMS I.22822-022. Distribution: Very rare in deeper water from southern Japan to Indonesia and NW-Australia. 86 103a 103c 103d 104 103b Figs. 103-104: Lepidoblepharon ophthalmolepis WEBER 1913 – 15 × Brachypleura GÜNTHER 1862 Type-species: Brachypleura novaezeelandiae GÜNTHER 1862 syn. Laiopteryx WEBER 1913 (type-species: Brachypleura xanthosticta ALCOCK = Brachypleura novaezeelandiae) Diagnosis: Thickset, compressed otoliths, almost circular in shape except for the very pronounced predorsal lobe. Dorsal rim irregular, sometimes with postdorsal angle which is situated far back along the dorsal rim, ventral rim deeply and regularly curving, anterior tip blunt, posterior tip broadly rounded or with obtuse angle; index l:h 1.0-1.1. Otolith size reaching just slightly over 3 mm. Sulcus shallow, relatively narrow, short, anteriorly closed and posteriorly terminating at some distance from the posterior tip of the otolith. Ostium slightly longer and wider than cauda. Ostium connected with anterior tip of otolith by faint ostial channel. Colliculi well developed and separated. Collum expanded ventrally, not filled with a colliculum. Dorsal and ventral depressions well developed but not completely fused behind cauda to form circumsulcal depression, running at considerable distance from the sulcus. Inner face relatively flat; outer face slightly convex, smooth. All rims thickset except for the thin dorsal rim and smooth. Measurements (ab.=about): l:h h:t novaezeelandiae (l) 1.00-1.10 ab. 3.0 novaezeelandiae (r) † pentagonalis (l) 1.10-1.15 ab. 3.0 † pentagonalis (r) † xenosulcis 1.10-1.20 2.5-3.0 ol:cl 1.15-1.40 1.55 0.85-1.10 1.70-1.90 1.50-1.95 oh:ch con.i 1.0-1.4 ab. 3.5 1.0-1.2 ab. 3.0 1.1-1.3 ab. 4.0 Side dimorphism: The only character seemingly affected by side dimorphism is the proportions of the sulcus. In left hand otoliths the cauda is comparatively longer and the ostium shorter than in otoliths of the right side. This finds its expression in the index ol:cl. It is most strongly developed in the fossil B. pentagonalis. However, in the second fossil species – genus aff. Brachypleura xenosulcis – even a mild degree of asymmetry is missing. Discussion: Brachypleura is characterized by two very specialized features – the predorsal projection and the ventrally widened collum. In this respect it clearly differs from the second genus of the family – Lepidoblepharon (see respective entry). Although the otolith pattern of Brachypleura definitely is more apomorphic in character, its fossil record since Upper Eocene indicates a long separation of the two genera. Species and distribution: One recent species – B. novaezeelandiae – from the Indo-West-Pacific on the lower shelf (50 to 100 m), one fossil species – Schwarzhans: Pleuronectiformes 87 105a 106 105b 105c 107 110 109 108 Figs. 105-110: Brachypleura novaezeelandiae GÜNTHER 1862 – 15 × B. pentagonalis – from the Lower Oligocene of France (Aquitaine Basin) and a second fossil species tentatively placed in this genus – genus aff. B. xenosulcis – from the Upper Eocene of Java. liths (left side) from the Ganjam coast, India (identified as B. xanthosticta), 1 ZMH Ot. 3.1.1994.3 (leg. BMNH 90.11.28.41-2) and 1 BMNH 90.11.28.41-2, 4 otoliths (left side, figs. 108-110) without location, ZMH Ot. 3.1.1994.4-7 (leg. ZMUC). Brachypleura novaezeelandiae GÜNTHER 1862 Figs. 105-110 Ontogeny and variability: Ontogenetic changes and variability is very limited in the specimens investigated. The smallest specimen investigated (fig. 110) is somewhat more gently rounded in outline and shows a less well developed predorsal lobe. syn. Brachypleura xanthosticta ALCOCK 1889 Investigated otoliths: 9 otoliths, 3 otoliths (2 left side and 1 right side, figs. 105-107) from the Arafura Sea, 2 ZMH Ot. 3.1.1994.1-2 (leg. BMNH 90.2.26.144-5) and 1 BMNH 90.2.26.144-5, 2 otoPiscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: The fossil B. pentagonalis differs from the recent species only in the less prominently developed predorsal projection and the poorly 88 112a 106 112b 113 114 112c Figs. 111-114: Brachypleura pentagonalis (STEURBAUT 1984) – 15 × developed ventral enlargement of the collum. Distribution: In the Indo-West-Pacific (India, Indonesian Archipelago and Philippines) on the lower shelf (50 to 100 m). The type-specimens were recorded to have been obtained from New Zealand (hence the etymology). NORMAN (1934), however, doubted the correctness of the type locality. So far, no additional specimens have been obtained from New Zealandian waters. Discussion: B. pentagonalis is a typical representative of the genus Brachypleura, differing from the recent B. novaezeelandiae merely in the less prominently developed predorsal projection and the lack of a ventrally enlarged collum. The latter character seemingly is a fairly recent achievement in Brachypleura. Otherwise, the fossil species from the Lower Oligocene proves the antiquity of the genus and the family. Distribution: Lower Oligocene of France (Aquitaine Basin). Brachypleura pentagonalis (STEURBAUT 1984) Figs. 111-114 syn. genus Pleuronectidarum pentagonalis STEURBAUT 1984 – STEURBAUT 1984: pl. 35, figs. 1-6 Investigated otoliths: 4 otoliths, the holotype (IRSNB P 4248, fig. 112) and 3 paratypes (IRSNB, figs. 111, 113, 114) from the Lower Oligocene of d’Yrieu, Aquitaine Basin (France). Ontogeny and variability: Like in B. novaezeelandiae ontogenetic changes and variability is very limited in this species, smaller specimens seemingly being somewhat more rounded in outline. genus aff. Brachypleura xenosulcis n.sp. Figs. 115-117 syn. genus Bothidarum sp. – NOLF & BAJPAI 1992: pl. 6, fig. 6-8 Name: xenos (gr.) = strange and sulcus (from Otolith terminology), referring to the sulcus morphology, which is somewhat atypical for the genus Brachypleura. Holotype: Fig. 115, IRSNB P 5967. Type locality: River outcrops about 4 km NW of Nanggulan, Java, Indonesia. Age: Nanggulan Formation, Early Bartonian Schwarzhans: Pleuronectiformes 89 116a 115a 115c 116c 117 115b 116b Figs. 115-117: genus aff. Brachypleura xenosulcis n.sp. – 25 × (NP16 Zone), Upper Eocene. Paratypes: 2 otoliths, topo- and stratitypic, IRSNB P 5968 and IRSNB P 5969 (fig. 116-117). Diagnosis: Compressed, small otoliths with almost circular outline. Predorsal projection feeble, posterior tip obtuse. Ostium 1 { to nearly 2 times as long as cauda, slightly widened ventrally near junction with cauda. Cauda slightly narrower than ostium and slightly curved. Circumsulcal depression incomplete. Description: Outline: Otoliths small (less than 2 mm), with a compressed, nearly circular outline. Dorsal rim highest anteriorly at the relative weekly developed predorsal projection; anterior and posterior tips obtuse; ventral rim deeply and regularly curving. Otoliths moderately thickset. Inner face: Moderately convex and rather smooth. Sulcus short, narrow, with slightly supramedian position, not much deepened. Ostium about 1 { to 2 times as long as cauda, somewhat widened, particularly ventrally in the area close to junction with cauda; ostial opening reduced, terminating at some distance from the anterior rim of the otolith. Cauda somewhat narrowed, slightly curving and slightly deepened, terminating at considerable distance from the posterior tip of the otolith. Separation of colliculi rather indistinct. Dorsal and ventral depressions well developed, but not connected around caudal tip of sulcus. Other views: Rims are moderately sharp and rather smooth. Outer face smooth, not as strongly convex as inner face. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: Not apparent. Ontogeny: The size of the three species ranges from 1.0 to 1.5 mm. The smallest specimen (fig. 117) is much more rounded in outline than the two larger ones, resulting in a more generalized appearance. The degree of allometric ontogenetic changes observed in the few specimens indicates that the two larger specimens are more less morphologically mature, i.e. rather represent a small species than juveniles. Discussion: genus aff. Brachypleura xenosulcis is quite unmistakable by the characters given in the diagnosis. It resembles other Brachypleura species in the outline, the reduced sulcus opening and the incomplete circumsulcal depression. It differs in the curved cauda, which may be regarded as a plesiomorphic character. Because of this, its placement in the genus Brachypleura must therefore be regarded as preliminary. It is quite possible that genus aff. Brachypleura xenosulcis represents an extinct fossil genus of the Brachypleuridae. 7.5 Scophthalmidae Genera: Scophthalmus, Lepidorhombus, Zeugopterus and Phrynorhombus. Definition and relationship: Scophthalmidae are left eyed flatfishes. They were first mentioned by NORMAN (1934) as a subfamily (Scophthalminae) of the Bothidae and then became elevated to family ranking by HUBBS (1945). The following 90 discussion is based on the analyses of HUBBS. Scophthalmidae are distinguished from Bothidae and Citharidae by the elongate pelvic fin bases. The gill-membranes are separated as in citharids, but not as widely; in bothids and pleuronectids they are united. From citharids (and brachypleurids, which are right eyed) they are further distinguished by the loss of the spine in the pelvic fin. This character, which scophthalmids share with bothids and pleuronectids, was regarded as an important synapomorphic character of the three families in LAUDER & LIEM’s phylogenetic analysis (1983). They placed Scophthalmidae in their cladogram between Citharidae (plesiomorphic outgroup) and Bothidae and Pleuronectidae (apomorphic ingroup). With otoliths alone it is difficult to define the limits of this small family since they exhibit quite a morphological variation. This finds its expression in three genus groups, based on otoliths, that I define as follows – Scophthalmus Group, Lepidorhombus Group and Zeugopterus Group. The Scophthalmus and Zeugopterus Groups bear more resemblance to each other than either do to the Lepidorhombus Group. The otoliths of the two former groups may be regarded as more plesiomorphic. They are characterized by a virtual lack of side dimorphism in otoliths, an outline that roughly resembles that seen in the otoliths of citharids, and an ostium which is slightly enlarged in width. These features and the distinct opening of the ostium which is evident in all Scophthalmidae are regarded as plesiomorphic. Lepidorhombus otoliths on the other hand show a more elongate shape with a less distinctive outline, and are also characterized by an extreme side dimorphism. Two apomorphic features are found in all scophthalmid otoliths. One is the nearly complete circumsulcal area which goes in hand with a relatively wide separation of the caudal tip from the rear end of the otolith. The other is the ratio ol:cl (ranging between 1.3 and 2.2, except for Zeugopterus where it can approach nearly 1.0) which reflects an early stage in the reduction of the length of the cauda. Those two characters represent an early stage in the development of the otolith morphology seen “in maturity” in the Bothidae and Pleuronectidae. In conclusion, otoliths of the scophthalmid genera do not contradict their being classified in one family – Scophthalmidae although they exhibit rather divergent morphological patterns. They also in principal support the phylogenetic concept proposed by LAUDER & LIEM. Distribution: The four genera of the Scophthalmidae are restricted to the temperate North Atlantic, the Mediterranean and the Black Sea, in both recent and fossil records. 7.5.1 Scophthalmus Group Genera: One genus – Scophthalmus – with three recent species from the temperate North Atlantic, the Mediterranean and the Black Sea. In addition there is one undescribed fossil species recorded from the Middle Miocene of southern Poland (Paratethys). It is the only group of the family recorded from the coasts of North America. Definition and relationship: Otoliths of the Scophthalmus Group seem to represent the most plesiomorphic in this family. They are thin, compressed in outline with a distinct predorsal angle. They resemble in shape somewhat Citharids. The sulcus is clearly opening anteriorly. The ostium is slightly to considerably longer than the cauda and also slightly wider. The cauda is gently curved over its entire length and terminates at some distance from the posterior rim of the otolith. The circumsulcal depression is shallow, but more or less complete. Otoliths of the Zeugopterus Group are quite similar merely looking like “dwarfed” specimens of Scophthalmus. Otoliths of the Lepidorhombus Group in contrary differ in several aspects (see respective entry). Scophthalmus RAFINESQUE 1810 Type-species: Pleuronectes rhombus LINNAEUS 1758 syn. Rhombus [non COSTA 1776] WALBAUM 1792 (type-species: Pleuronectes rhombus) syn. Rhomboides GOLDFUSS 1820 (type-species: Pleuronectes rhombus) syn. Psetta CUVIER 1817 (type-species: Pleuronectes maximus) syn. Lophopsetta GILL 1862 (type-species: Pleuronectes maculatus MITCHILL 1814 = Scophthalmus aquosus) Schwarzhans: Pleuronectiformes 91 Diagnosis: Thin, compressed otoliths; ventral rim deeply and regularly curving, deepest slightly anterior of the middle, dorsal rim with prominent predorsal angle and indistinct postdorsal angle situated far backwards close to the posterior rim, posterior tip blunt or with indistinct obtuse angle, anterior rim with very short rostrum, but without excisura; index l:h 1.2 to 1.4. Otolith size up to 14 mm, but usually smaller than 10 mm. Ostium slightly wider than cauda and slightly to considerably longer, anteriorly open, rather shallow. Cauda straight to very gently curving over the whole length, terminating at some distance from the posterior rim of the otolith. Dorsal and ventral depressions shallow, often indistinct, more or less connected around caudal tip to form a circumsulcal depression. Inner face slightly convex; outer face slightly concave, smooth to slightly ornamented. Rims sharp, often crenulated or irregularly undulating. Measurements: rhombus maximus aquosus l:h h:t ol:cl 1.25-1.45 4.0-4.5 1.75-2.0 1.30-1.60 4.0-4.5 1.35-1.75 1.35 4.0 1.30 oh:ch con.i 1.2-1.3 about 3.5 1.1-1.3 3.0-3.5 1.1 about 3.5 Side dimorphism: Not apparent or else hidden by the relatively wide intraspecific variability. Ontogeny and variability: CHAINE (1936) has figured large series of S. rhombus and S. maximus. From his figures it appears that ontogenetic changes are not very significant. Even small specimens in the range of 3 to 4 mm are diagnostically valid. The smallest otolith in my collection, however, which is about 1.5 mm long, has not developed all pertinent diagnostic features. Variability to the contrary can be quite significant. In particular details of the outline and length to height proportions are apt to variations. Discussion: See discussion in entry to group. Species and distribution: Three recent species – S. rhombus in the Mediterranean, Black Sea and the NE-Atlantic from northernmost Morocco to southern Norway, S. maximus with the same distribution pattern but also occurring of Iceland, and S. aquosus from the Atlantic coast of North America from Casco Bay to South Carolina. In addition there is a single juvenile fossil record Piscium Catalogus, Part Otolithi piscium, Vol. 2 from the Middle Miocene of southern Poland (Paratethys) described by RADWANSKA (1992) as Scophthalmus sp. (fig. 155, pl. 37, figs. 8-10) (see fig. 122). Scophthalmus maximus (LINNAEUS 1758) Figs. 118-121 syn. syn. syn. syn. Pleuronectes turbot LACEPEDE 1802 Pleuronectes tuberculatus SHAW 1803 Pleuronectes cyclops DONOVAN 1806 Pleuronectes maeoticus PALLAS 1814 (subspecies) syn. Rhombus aculeatus GOTTSCHE 1835 syn. Rhombus stellosus BENNETT 1835 syn. Scophthalmus ponticus NINNI 1932 Investigated otoliths: 6 otoliths, 2 (right side, fig. 121) from off Portugal, south of Lisboa, one otolith ZMH Ot. 3.1.1994.8 (leg BMNH 94.3.29.67), the other BMNH 94.3.29.6-7, 4 (left and right side, figs. 118-120), North Sea, ZMH Ot. 2.1.1995.58 (coll. Schwarzhans). Ontogeny and variability: See entry to genus. A large series of otoliths from this species has been figured by CHAINE (1936). Discussion: S. maximus differs from the parallelly occurring S. rhombus in the comparatively longer cauda and in being slightly more elongate. S.aquosus shows similar sulcus proportions but has a much less developed predorsal angle. Distribution: Mediterranean, Black Sea, and NEAtlantic from southern Norway to northernmost Morocco and from Iceland. Scophthalmus rhombus (LINNAEUS 1758) Fig. 123 syn. syn. syn. syn. syn. Pleuronectes cristatus LICHTENSTEIN 1801 Pleuronectes laevis TURTON 1802 Rhombus barbatus RISSO 1826 Pleuronectes lioderma NARDO 1827 Platessa pavonina COSTA 1847 Investigated otoliths: 1 otolith (right side) from off Plymouth, England, BMNH 1988.10.11.18-23. 92 118 119a 119b 120 121 Figs. 118-121: Sophthalmus maximus (LINNAEUS 1758) – 10 × Ontogeny and variability: See entry to genus. A large series of otoliths has been figured by CHAINE (1936). Investigated otoliths: 1 otolith (right side) from the coast of Connecticut, USA, BMNH 79.10.9.66. Ontogeny and variability: No data. Discussion: Otoliths of S. rhombus are characterized by their relatively short cauda. Distribution: Mediterranean, Black Sea, and NEAtlantic from southern Norway to northernmost Morocco. Scophthalmus aquosus (MITCHILL 1815) Fig. 124 syn. Pleuronectes maculatus MITCHILL 1814 (preoccupied) a b Fig. 122: Scophthalmus sp. – 10 × Discussion: Otoliths of S. aquosus are recognized by the combination of the relatively long cauda which is almost as wide as the ostium and the moderate predorsal angle. They resembles closest otoliths of S. maximus. Distribution: NW-Atlantic, coasts of North America from Casco Bay to South Carolina. 7.5.2 Lepidorhombus Group Genera: One genus – Lepidorhombus – with two recent species in the NE-Atlantic and the western Mediterranean and three fossil species from the Upper Oligocene to the Upper Miocene of the North Sea Basin and the Paratethys. One of the two recent species – L. whiffiagonis – has also been recorded as fossil from the Pliocene of the North Sea Basin. Schwarzhans: Pleuronectiformes 93 c a b Fig. 123: Scophthalmus rhombus (LINNAEUS 1758) – 10 × Definition and relationship: Otoliths of the genus Lepidorhombus differ in a number of aspects from those of the other genera in the family Scophthalmidae. For one thing they are the only genus with a pronounced side dimorphism in otoliths. Furthermore they are characterized by a more gently curved outline, a more massive rostrum, the more strongly reduced size of the cauda which is oval in shape, and the rather strongly developed and complete circumsulcal depression. From otolith analysis it seems that the Lepidorhombus Group occupies a somewhat separated position within the Scophthalmidae. Judging from otoliths alone Lepidorhombus could also be placed in the Bothidae, for instance close to the Paralichthys Group. distance from the posterior rim of the otolith. Dorsal and ventral depressions deep, wide, well connected around caudal tip to form a circumsulcal depression. Inner face almost flat; outer face flat to slightly concave, smooth, sometimes with postdorsal ridge. Rims sharp, smooth or slightly and irregularly undulating. Measurements (ab. = about): whiffiagonis (left) whiffiagonis (right) boscii (left) boscii (right) †subtriangularis (l) †subtriangularis (r) †angulosus (left) †klockenhoffi (l) l:h 1.60-1.70 1.55-1.60 1.35-1.50 1.30-1.45 1.65-1.85 1.55-1.80 1.45-1.55 1.10-1.25 h:t 3.5 4.5 ab. 5.0 ab. 5.0 2.5-3.5 3.5 3.5-4.0 ol:cl 2.1-2.2 1.5-1.6 2.0-2.2 1.65-1.8 1.6-1.8 1.25-1.4 1.5-2.2 1.6-2.0 oh:ch con.i 1.0-1.2 5-6 7-8 0.9-1.1 5-6 6-7 1.1-1.35 4.5 1.0-1.1 6.5 1.1-1.35 4-5 1.1-1.2 nm Lepidorhombus GÜNTHER 1862 Type-species: Pleuronectes megastoma DONOVAN 1804 (syn. L. whiffiagonis) Diagnosis: Thin, roundish to moderately elongate otoliths; ventral rim shallow to moderately deep, regularly curving, dorsal rim gently curving in left sided otoliths, with prominent postdorsal angle in right sided otoliths, predorsal angle indistinct, posterior tip rounded or pointed, anterior rim with relatively strong massive rostrum, but without excisura; index l:h 1.1 to 1.85. Otolith size up to 10 mm, but usually smaller than 7 mm. Specimens from about 3 to 4 mm seem to be morphologically mature. Ostium slightly wider than cauda but considerably longer, anteriorly open, moderately deep. Cauda short, oval in shape, terminating at some Piscium Catalogus, Part Otolithi piscium, Vol. 2 a b c Fig. 124: Scophthalmus aquosus (MITCHILL 1815) – 10 × 94 125a 126a 126c 125b 126b 128 127 Figs. 125-128: Lepidorhombus whiffiagonis (WALBAUM 1792) – 6 × Side dimorphism: Otoliths of the genus Lepidorhombus exhibit a remarkable degree of side dimorphism, one of the largest to be seen in Pleuronectiforms. The features are: Sulcus shape and depth: Otoliths of the eyed side show a much deeper sulcus with a proportionally shorter cauda. Separation of colliculi: Otoliths of the blind side usually show well separated colliculi, whereas in otoliths of the eyed side they are almost completely fused. Otolith proportions: Otoliths of the eyed side are often more elongate than those of the blind side. Outline of otolith: Otoliths of the blind side show a rather gently curved dorsal rim, whereas those of the eyed side exhibit a strong postdorsal angle. Also, in otoliths of the eyed side the rostrum is more massive. Rims of otoliths of the eyed side are usually smoother than those of the blind side. Circumsulcal depression: In otoliths of the eyed side the circumsulcal depression is less well limited towards the cauda and usually shallower than in otoliths of the blind side. Also, otoliths of the eyed side often show multiple radial ridges and furrows crossing the rear part of the circumsulcal depression. Curvature of the inner face: The inner faces of otoliths of the eyed side are usually more convex than those of the blind side, particularly so in the vertical direction. It must be noted, however, that the degree of side dimorphism in otoliths is somewhat variable from species to species. It is strongest in L. whiffiagonis and L. subtriangularis, but less well developed in L. boscii. Ontogeny and variability: CHAINE (1936) has figured a large set of otoliths from the two recent species. From his figures it appears that ontogenetic changes of otoliths down to about 4 to 5 mm in length are rather inconspicuous. They have often developed a ridge or knob situated postdorsally on the outer face. In specimens smaller than 3 to 4 mm this character usually is not developed. Intraspecific variability, on the other side, is relatively strong. Both otolith and sulcus proportions may be affected to a certain extend as well as details of the outline and its ornamentation. Discussion: See entry to Lepidorhombus Group. Species and distribution: Two recent species – L. whiffiagonis in the western Mediterranean and Schwarzhans: Pleuronectiformes 95 131c 131a 129 131b 130 Figs. 129-131: Lepidorhombus boscii (RISSO 1810) – 6 × in the NE-Atlantic found on the deep shelf down to 400 m, and L. boscii with the same distribution pattern but found in depths down to 800 m. L. whiffiagonis is also known as fossil from the Pliocene of Belgium. In addition there are three fossil species – L. subtriangularis from the Upper Oligocene to Middle Miocene of the North Sea Basin and the Middle Miocene of Austria and Poland (Paratethys), L. angulosus from the Lower and Middle Miocene of the North Sea Basin, and L. klockenhoffi from the Upper Miocene of the North Sea Basin. Discussion: Otoliths of L. whiffiagonis are readily distinguished from those of the other recent species – L. boscii – in being more elongate. The ventral rim is curving more shallow. Otoliths of the eyed side show a much stronger postdorsal angle than those of L. boscii. Lepidorhombus whiffiagonis (WALBAUM 1792) Figs. 125-128, 14 Lepidorhombus boscii (RISSO 1810) Figs. 129-131 syn. syn. syn. syn. syn. Pleuronectes megastoma DONOVAN 1804 Pleuronectes pseudopalus PENNANT 1812 Pleuronectes (Rhombus) cardina CUVIER 1829 Lepidorhombus megastoma borealis KYLE 1913 Lepidorhombus whiffiagonis – otoliths: GAEMERS & SCHWARZHANS 1973: pl. 3, fig. 38; pl. 10, fig. 7 Investigated otoliths: 4 otoliths (2 left side and 2 right side) from the North Sea, ZMH Ot. 5.1.1994.1-4 (coll. Schwarzhans). Ontogeny and variability: See entry to genus. A large series of otoliths has been figured by CHAINE (1936). Side dimorphism: L. whiffiagonis is one of the species of this genus with a very strongly developed side dimorphism (see entry to genus). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Western and Central Mediterranean and NE-Atlantic from southern Norway and Iceland to southern Morocco (Cape Bojador). L. whiffiagonis is also known as fossil from the Lower Pliocene of Belgium. Investigated otoliths: 3 otoliths, 2 (right and left side, figs. 129-130) from Banjules, France, Western Mediterranean, BMNH 1976.7.30.270-4, 1 otolith (right side, fig. 131) from off Malta, 25°44’N/ 15°07’E, ZMH Ot. 5.1.1994.5 (leg. ZMUC 853446). Ontogeny and variability: See entry to genus. A large series of otoliths has been figured by CHAINE (1936). Side dimorphism: Otolith asymmetry is less strongly developed in L. boscii than in other species of the genus. Sulcus proportions are practically identical between otoliths from the eyed and from the blind sides. Also the development of the postdorsal angle is much less differential than for instance in L. whiffiagonis. Discussion: See L. whiffiagonis. 96 133 132a 132c 132b 134a 134b Figs. 132-134: Lepidorhombus subtriangularis HEINRICH 1970 – 15 × Distribution: Western Mediterranean and NEAtlantic from Scotland to southern Morocco (Cape Bojador). A fossil record of this species from the Pliocene of Belgium (NOLF, 1978) is based on a very eroded otolith and therefore may not be regarded as valid. Lepidorhombus subtriangularis HEINRICH 1970 Figs. 132-142 syn. Rhombus rhenanus KOKEN – SCHUBERT 1906: pl. 6, fig. 15 syn. Lepidorhombus subtriangularis HEINRICH 1970 – HEINRICH 1970: fig. 1 syn. Solea subglabra SCHUBERT – SMIGIELSKA 1973: pl. 5, fig. 9 syn. Lepidorhombus angulosus NOLF 1976 (pars) – NOLF 1976: pl. 17, fig. 15 (non fig. 16 = holotype) syn. Lepidorhombus angulosus NOLF – RADWANSKA 1992: fig. 154; pl. 37, figs. 1-7 syn. Scophthalmus sp. – RADWANSKA 1992 (part): fig. 155; pl. 37, figs. 9-10 (non pl. 37, fig. 8 – Scophthalmus sp.) syn. Lepidorhombus aff. subtriangularis – MÜLLER 1994: pl. 10, fig. 5 syn. Lepidorhombus subtriangularis – SCHWARZHANS 1994: figs. 517-521 Investigated otoliths: 24 otoliths, 6 otoliths from the Upper Oligocene of various locations in northern Germany (2 figured from Ratingen, coll Klinger, left side, figs. 133-134), 1 otolith (left side, fig. 132) from well Wetten near Goch, northern Germany, Reinbekian, Middle Miocene, coll. Wienrich, and as L. aff. subtriangularis 2 otoliths (right side) from Bad Vöslau, Austria, Badenian, Middle Miocene, GBW 1906/1/69 (originally identified by SCHUBERT, 1906 as Rhombus rhenanus) and 14 otoliths (figs. 135-142) from Rybnica, Poland, Badenian, Middle Miocene, ZPalUWRaR 418-426, 427-429 (coll. Radwanska). Ontogeny and variability: The largest otolith of this species known so far is the well preserved holotype of HEINRICH (1970), which is about 5.5 mm long. This specimen and the one of fig. 132, which is about 4 mm long seemingly represent a mature morphological stage. The smaller ones are lacking the horizontal ridge or knob situated postdorsally on the outer face. A feature of considerable variability is the postdorsal angle in left sided otoliths. It is strongly developed in the well preserved holotype of Schwarzhans: Pleuronectiformes 97 136a 135 136b 137a 138 137b 139 140 141 142 Figs. 135-142: Lepidorhombus aff. subtriangularis HEINRICH 1970 – 15 × HEINRICH (1970) and the specimen figured as a paratype of L. angulosus by NOLF (1976). Figures by RADWANSKA (1992) and those otoliths figPiscium Catalogus, Part Otolithi piscium, Vol. 2 ured here show both strong and feeble postdorsal angles. However, the otoliths from the Middle Miocene of Austria and Poland in general are 98 143b 143c 143a 144a 144b 146 145a 145b Figs. 143-146: Lepidorhombus angulosus NOLF 1976 – 15 × a little more slender and do not show the postdorsal thickening of the outer face, which seems to be typical at least for the larger specimens from the North Sea Basin. Eventually, once more material has become available, they might be regarded as a different species altogether. For the time being I recommend to leave them as L. aff. subtriangularis (figs. 135-142). Side dimorphism: Like L. whiffiagonis, L. subtriangularis too exhibits a rather strong degree of side dimorphism. This can be seen best in a series of both left and right sided otoliths from Poland (figs. 135-142; see also RADWANSKA, 1992). Specimens from the Tertiary of the North Sea Basin so far have almost exclusively been left sided. Discussion: L. subtriangularis resembles in all aspects the recent L. whiffiagonis. Differences if any are the slightly more elongate appearance and the comparatively longer cauda (index ol:cl, see list to genus). Larger otoliths of L. subtriangularis seem to be more thickset than those of L. whiffiagonis due to the strong postcentral ridge or knob on the outer face (apparent only in specimens from the North Sea Basin). Anyway, both species apparently are closely related, i.e. L. subtriangularis may represent the ancestor of L. whiffiagonis. Schwarzhans: Pleuronectiformes 99 149 147 148 150 Figs. 147-150: Lepidorhombus klockenhoffi GAEMERS & SCHWARZHANS 1982 – 10 × Distribution: Upper Oligocene to Middle Miocene of the North Sea Basin and as L. aff. subtriangularis (figs. 135-142) also from the Middle Miocene of the northern Paratethys (Austria and Poland). It may additionally be expected in the Middle Miocene of the Atlantic European Basins, although not proven as yet despite extensive research (STEURBAUT, 1984). Lepidorhombus angulosus NOLF 1976 Figs. 143-146 syn. Lepidorhombus angulosus NOLF 1976 (pars) – NOLF 1976: pl. 17, fig. 16 (holotype), non fig. 15 (L. subtriangularis) syn. Lepidorhombus angulosus – MENZEL 1986: pl. 9, fig. 3 Investigated otoliths: 5 otoliths, 1 otolith (left side, fig. 143), well Lüllingen near Goch, northern Germany, Hemmoorian to Reinbekian, Lower to Middel Miocene, coll. Wienrich, 1 otolith (left side, fig. 145), well UWO 36 Hellwege near Ahaus (129-132 m), northern Germany, Hemmoorian, Lower Miocene, NLB 11732 (ident. and leg. Menzel), 1 otolith (right side, fig. 144), well Wetten near Goch, northern Germany, Reinbekian, Middle Miocene, coll. Wienrich, 1 otolith (left side) from Dingden near Bocholt, northern Germany, Reinbekian, Middle Miocene, coll. Schwarzhans, 1 small otolith (right side, fig. 146) from quarry Sunder at Twistringen near Bremen, Reinbekian, Middle Miocene, coll. Schwarzhans. Ontogeny and variability: The few specimens known so far do not allow analysis of ontogenetic changes or variability. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: Although known from very few specimens so far, it seems that side dimorphism is not very strongly developed in this species, comparable may be to L. boscii. Discussion: L. angulosus differs from the parallelly occurring L. subtriangularis in being more compressed and more thinset. In these respects it resembles closely the recent L. boscii (also in the degree of side dimorphism, see above). Otoliths of L. boscii seem to be even more compressed and usually exhibit a shorter cauda (see index ol:cl in listing to genus). However, morphological differences are so small that a very close relationship is being postulated. This indicates that the lineage L. angulosus – L. boscii has been separated from the lineage L. subtriangularis – L. whiffiagonis for a considerable time span. Distribution: Lower (?) and Middle Miocene of the North Sea Basin (Belgium and northern Germany). Lepidorhombus klockenhoffi GAEMERS & SCHWARZHANS 1982 Fig. 147-150 syn. Lepidorhombus klockenhoffi GAEMERS & SCHWARZHANS 1982 – GAEMERS & SCHWARZHANS 1982: pl. 8, figs. 6-11 Investigated otoliths: 17 otoliths (all type-material) from the Isle of Sylt, northern Germany, Syltian, Upper Miocene, figured specimens are fig. 147 (holotype, left side, RGM 176 674) and figs. 148-150 (paratypes, 2 left and 1 right side, RGM 176 684). 100 152 151c 151a 153a 151b 153b Figs. 151-153: Zeugopterus punctatus (BLOCH 1787) – 15 × Ontogeny and variability: The largest otolith known to date is about 3.6 mm long and may not be fully mature. Variability is particularly evident in the development of the postdorsal and the posterior rims. Usually, the postdorsal angle is pronounced and the posterior rim blunt, but some otoliths show a weak postdorsal rim and a somewhat angular to pointed posterior tip (not figured). It looks as if the postdorsal angle has moved downward. Side dimorphism: Practically all right handed otoliths are poorly preserved and therefore only one specimen is figured. It seems that right handed otoliths are more roundish in shape with feeble postdorsal angles and a weak rostrum. Discussion: L. klockenhoffi is easily recognized by its extreme compressed appearance. It apparently represents a third yet extinct lineage within the genus Lepidorhombus. Distribution: Known exclusively from the type locality. 7.5.3 Zeugopterus Group Genera: Two genera – Zeugopterus – with one recent species from the North Sea and one fossil species from the Upper Oligocene of the North Sea Basin, and – Phrynorhombus – with two recent species from the European coast of the Atlantic and the Western Mediterranean and one fossil species from the Miocene of the North Sea Basin. Definition and relationship: Otoliths of the Zeugopterus Group in many aspects resemble those of Scophthalmus, single genus of the Scophthalmus Group. In fact, they somehow look like dwarfed Scophthalmus otoliths. Otoliths of the Zeugopterus Group are relatively small in size like the fishes themselves, too. The ostium is just slightly longer and wider than the cauda. The cauda sometimes shows an incipient and very gently curvature over its whole length. The circumsulcal depression is complete in both genera, although sometimes quite feeble. I assume that the Zeugopterus Group represents a specialized offshot from near the Scophthalmus Group. Zeugopterus GOTTSCHE 1835 Type-species: Pleuronectes hirtus ABILDGAARD 1789 (syn. Z. punctatus) Diagnosis: Moderately thin, compressed otoliths; ventral rim regularly curving, deepest at about the middle, dorsal rim with rounded predorsal angle and usually prominent postdorsal angle situated far backwards close to the posterior rim, posterior tip with obtuse angle, anterior rim with short, sometimes massive rostrum, but without excisura; index l:h 1.25 to 1.65. Otolith size not exceeding 2.5 mm, morphologically mature from about 1.5 mm. Ostium markedly wider than cauda and only slightly longer, anteriorly open, moderately deep. Cauda straight to very gently curving over the whole length, terminating relatively close to the posterior rim of the otolith. Dorsal and ventral Schwarzhans: Pleuronectiformes 101 154c 156 155a 154a 154b 155b 157 Figs. 154-157: Zeugopterus rosenthalensis (WEILER 1942) – 15 × depressions shallow, often indistinct, but connected around caudal tip to form a circumsulcal depression. Inner face slightly convex, particularly so in the vertical direction; outer face slightly concave, smooth. Rims sharp, sometimes irregularly undulating. Measurements: punctatus †rosenthalensis l:h 1.25-1.40 1.40-1.55 h:t 3.0 3.0 ol:cl 1.05-1.2 1.15-1.35 oh:ch 1.2-1.7 1.1-1.5 con.i 3.5-4.0 3.5-4.0 Side dimorphism: Not apparent. Ontogeny and variability: Ontogenetic changes do not seem to be very drastic. Small otoliths of 1.5 mm or less just look more generalized and “smoothed” in outline. Variability to the contrary is considerable. It affects aspects of the outline, and proportions of otolith and sulcus to some extent. Discussion: Fishes and otoliths of Zeugopterus grow to larger sizes than those of Phrynorhombus. This is probably the reason why they look less “reduced” in otolith morphology. Outline of the otolith, proportions of the sulcus and shape of the cauda still resembles Scophthalmus very much. In Phrynorhombus for instance the gentle curvature of the cauda is completely reduced, the cauda ovally shaped. Species and distribution: One recent species – Z. punctatus – in the North Sea, and one fossil species – Z. rosenthalensis – from the Upper Oligocene of northern Germany. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Zeugopterus punctatus (BLOCH 1787) Figs. 151-153 syn. Pleuronectes hirtus ABILDGAARD 1789 syn. Zeugopterus papillosus BROOK 1886 Investigated otoliths: 3 otoliths, (2 right, 1 left side) off Plymouth, ZMH Ot. 5.1.1994.6 (leg. BMNH 1988.10.11.27-29) and BMNH 1988. 10.11.27-29. Ontogeny and variability: See entry to genus. Discussion: Z. punctatus differs from the fossil Z. rosenthalensis in being more compressed and showing a more angularly developed dorsal rim. Also in Z. rosenthalensis the cauda is completely straight. Distribution: North Sea from southern Norway thru the channel to the Bay of Biscay mainly on stones and rocks in the algal zone. In addition there is a possible record from the Pliocene of Belgium by NOLF (1978; as Zeugopterus cf. punctatus). His drawing, however, does not allow for a reliable identification. Zeugopterus rosenthalensis (WEILER 1942) Figs. 154-157 syn. Bothus rosenthalensis WEILER 1942 – WEILER 1942: pl. 5, fig. 1 syn. Bothidarum rosenthalensis – SCHWARZHANS 1974: fig. 68 syn. Zeugopterus rosenthalensis – SCHWARZHANS 1994: figs. 512-516 102 Investigated otoliths: 17 otoliths from various locations from the Upper Oligocene of northern Germany, figured specimens, 1 otolith (left side, fig. ) shaft Sophia Jacoba 8 near Hückelhoven (279-282.5 m), coll. von der Hocht, 1 otolith (left side, fig. ) from well in Krefeld-Uerdingen, coll. Schwarzhans, 2 otoliths (1 left side, 1 right side, figs.) from well near Willich, coll. von der Hocht. Variability: Variations concern details of the outline and proportions of otolith and sulcus. Discussion: Z. rosenthalensis differs from the recent Z. punctatus in being more elongate, showing a more regularly rounded dorsal rim and a rather massive rostrum. Also the cauda is completely straight. In these aspects, particularly so the shape of the cauda, Z. rosenthalensis also resembles otoliths of Phrynorhombus. In fact, this species seems like being morphologically intermediate between the two closely related genera. Distribution: Upper Oligocene of northern Germany (North Sea Basin). Phrynorhombus GÜNTHER 1862 Type-species: Rhombus unimaculatus RISSO 1826 (syn. P. regius) Diagnosis: Moderately thin, compressed otoliths; ventral rim deeply and regularly curving, deepest at about the middle, dorsal rim irregular sometimes with pre- and postdorsal angles or mediodorsal angle, posterior tip blunt or with obtuse angle, anterior rim without or with very short rostrum, but without excisura; index l:h 1.15 to 1.45. Otolith size up to 2.5 mm, but usually smaller than 2 mm. Ostium wider and longer than cauda, anteriorly open, moderately deep. Cauda straight, oval in shape, terminating at some distance from the posterior rim of the otolith. Dorsal and ventral depressions marked, well connected around caudal tip to form a circumsulcal depression. Sometimes dorsal and/or ventral depression are crossed by radial furrows in otoliths of both sides. The dorsal and ventral cristae of the cauda are often prominent, sometimes tubercular. Inner face flat to slightly convex; outer face flat to slightly concave, smooth. Rims moderately sharp, sometimes irregularly undulating. Measurements: norvegicus †medius l:h h:t ol:cl 1.15-1.25 about 3.0 1.2-1.75 1.30-1.45 3.0-3.7 1.05-1.35 oh:ch 1.1-1.6 1.0-1.2 con.i 3.0-4.0 5.4-5.7 Side dimorphism: Side dimorphism in this genus is masked by the very high degree of the intraspecific variability. It seems that otoliths of the eyed side are just slightly more elongate. Ontogeny and variability: Practically all Phrynorhombus otoliths known so far are between 1.5 and 2.5 mm large. Within this size distribution ontogenetic changes are not apparent. Variability within the species of this genus is extremely high. There is almost no character which remains uninfluenced. Outline, proportions of otolith and sulcus vary to quite some extent. Diagnosis of species will depend on large otolith series and even then distinction of them will not always be possible. Discussion: Otoliths of the genus Phrynorhombus are very small and look like “dwarfed” Scophthalmus otoliths in many ways. In fact, they are even smaller than the otoliths of the related genus Zeugopterus. Morphologically, they are also more generalized, for instance as far the sulcus is concerned. This makes recognition of isolated otoliths of Phrynorhombus very difficult. The low diagnostic value of Phrynorhombus otoliths will make it even difficult at times to safely distinguish them from juvenile otoliths of some other Pleuronectiform genus. Apart from the difficulties in recognizing Phrynorhombus otoliths they certainly resemble Zeugopterus otoliths, and in my opinion both genera are closely related. Species and distribution: Phrynorhombus contains two recent species – P. norvegicus from the North Sea, northern Norway to the Bay of Biscay and Iceland and P. regius from the British Isles to Gibraltar and in the western Mediterranean. There is one fossil record – P. medius – from the Lower to Upper Miocene of northern Germany (North Sea Basin). A second fossil record – P. bassolii – by SCHUBERT (1906) from the Middle Miocene of Austria (Paratethys) does not represent a Pleuronectiform (see chapter 4.2). Schwarzhans: Pleuronectiformes 103 158 159 160a 161a 161b 160c 162a 162b 160b Figs. 158-162: Phrynorhombus norvegicus (GÜNTHER 1862) – 15 × Phrynorhombus norvegicus (GÜNTHER 1862) Figs. 158-162 of P. norvegicus in exhibiting a more pronounced rostrum. Investigated otoliths: 7 otoliths (4 left and 3 right side) from SW-England, IRSNB (coll. Nolf). Distribution: From the British Isles to Gibraltar and in the western Mediterranean on rocky bottoms between 10 and 180 m. Ontogeny and variability: See entry to genus. The 5 otoliths figured have been selected to give an impression of the variability occurring in this species. Discussion: Otoliths of P. norvegicus differ from those of the other recent species – P. regius – in the absence of a distinct rostrum. Distribution: Iceland, Norway, British Isles and France south to the Bay of Biscay on rocky bottoms between 10 and 180 m. Phrynorhombus regius (BONNATERRE 1788) syn. syn. syn. syn. syn. Pleuronectes calimanda LACEPEDE 1802 Pleuronectes uniocellatus NARDO 1824 Rhombus unimaculatus RISSO 1826 Rhombus setiger MICHAHELLAS 1829 Pleuronectes saxatilis NARDO 1847 Discussion: I have not investigated otoliths of this species. CHAINE (1936) has figured a number of otoliths from both recent Phrynorhombus species. Unfortunately, his figures are very small and do not allow for a detailed analysis. Anyhow, it seems that otoliths of P. regius differ from those Piscium Catalogus, Part Otolithi piscium, Vol. 2 Phrynorhombus medius WEILER 1958 Figs. 163-165 syn. Phrynorhombus medius WEILER 1958 – WEILER 1958: pl. 3, fig. 16 ?syn. Phrynorhombus medius – GAEMERS & SCHWARZHANS 1982: pl. 2, fig. 6 syn. Bothidarum obliquus MENZEL 1986 – MENZEL 1986: pl. 8, fig. 10; pl. 10, fig. 6 Investigated otoliths: 5 otoliths, the holotype of Bothidarum obliquus (right side, fig. 165) from well UE 45 Wistedt near Zeven, Lower Saxonia, Hemmoorian, Lower Miocene, NLB 11733 (leg. Menzel), 2 otoliths (right side, fig. 163, 164) from well Oxlund (105-128 m), Schleswig-Holstein, Hemmoorian, Lower Miocene, coll. Martini (leg. Anderson), 2 otoliths (left side, one figured in GAEMERS & SCHWARZHANS, 1982), Morsum Kliff, Isle of Sylt, Syltian, Upper Miocene, RGM 176 688-689. Ontogeny and variability: Variability like in all Phrynorhombus otoliths is considerable, mostly concerning proportions of otolith and sulcus. The otolith of fig. 164 is remarkable for its considera- 104 165a 163a 163c 164a 163b 164b 165b 165c Figs. 163-165: Phrynorhombus medius WEILER 1958 – 15 × bly more compressed and roundish outline. It could possibly represent a distinct species, but since it is a unique specimen of a genus known for its high variability it could also represent just an extreme variation. Discussion: Otoliths of P. medius seem to grow to slightly larger sizes than those of the two recent species. In general their otoliths are slightly more elongate and the ostium is usually not as much longer as the cauda (see index ol:cl in listing to genus). The latter character also distinguishes them from parallelly occurring juveniles of Lepidorhombus spp. Distribution: Lower to Upper Miocene of northern Germany. 7.6 Bothidae Genera: The Bothidae as recognized here contains some 39 living genera. In alphabetical order they are: Achiropsetta, Ancylopsetta, Arnoglossus, Asterorhombus, Bothus, Caulopsetta, Cephalopsetta, Chascanopsetta, Citharichthys, Crossorhombus, Cyclopsetta, Engyophrys, Engyprosopon, Etropus, Gastropsetta, Grammatobothus, Hippoglossina, Japonolaeops, Kamoharaia, Laeops, Lioglossina, Lophonectes, Mancopsetta, Monolene, Neolaeops, Orthopsetta, Parabothus, Paralichthys, Pelecanichthys, Perissias, Psettina, Pseudorhombus, Syacium, Taeniopsetta, Tarphops, Thysanopsetta, Tosarhombus, Trichopsetta, Xystreurys. Definition and relationship: In NORMAN (1934) the Bothidae were understood as an assemblage of all left eyed Pleuronectoidei, includ- ing of what are now the Citharidae and the Scophthalmidae. He distinguished three subfamilies – Paralichthyinae, Bothinae and Scophthalminae – based on the nature of the pelvic fin bases and presence or absence of transverse apophyses in the caudal vertebrae. HUBBS (1945) separated Scophthalmidae and Citharidae from Bothidae as distinct families (see entry to Citharidae and Scophthalmidae). In some recent literature Paralichthyinae have also been distinguished as a separate family (see NELSON 1984). EVSEENKO (1984) and GON & HEEMSTRA (1990) placed the two genera Achiropsetta and Mancopsetta in a family of their own – the Achiropsettidae. Comparing the characters listed by NORMAN there are indeed some features, for instance in the genus Mancopsetta, which do distinguish them from other bothids (see also HENSLEY & AHLSTROM 1984). These are the median position of the vent in front of the anal fin, the position of the tip of the dorsal fin behind the posterior nostril of the blind side (both presumably plesiomorphic characters), the loss of pectoral fins (an apomorphic character) and the pattern of the hypurals. – These alternative views raise the question whether the Bothidae in its wider sense may not represent a polyphyletic assemblage, even after extraction of the Citharidae and the Scophthalmidae. Otolith analyses might offer support for a solution but the available evidence is rather feeble and I have therefore selected to retain Bothidae as a single family in the sense of HUBBS (1945) with two subfamilies (Bothinae and Paralichthyinae) in the sense of HENSLEY & AHLSTROM (1984). The only exception from this is the genus Tephrinectes which I have removed from the Bothidae and placed into a category of uncertain relationship close to Psettodidae and Citharidae solely on the Schwarzhans: Pleuronectiformes 105 base of otolith analysis (see entry to Tephrinectes Group, chapters 7.2. and 7.2.1). Otoliths of Bothidae exhibit a wide range of morphological patterns that do not allow for a simple definition as a family. In general terms the cauda is already quite reduced in length, width and morphology (i.e. it is straight with a rounded tip). The circumsulcal depression is complete or nearly complete around the posterior tip of the cauda. These are the main distinctions from the more plesiomorphic families such as Psettodidae, Citharidae or Scophthalmidae, although somewhat intermediate forms particularly towards the pattern seen in the Scopthalmidae do exist. The ostium can be clearly open anteriorly even with development of an excisura, but more commonly it is closed sometimes terminating at a considerable distance from the anterior rim of the otolith. In this respect bothid and pleuronectid otoliths are often quite similar, although in Pleuronectinae the reduction of the sulcus opening is usually more strongly developed. In fact placement of otoliths in either the one or other family often depends very much on correlation at the generic level. Then, however, the taxonomic problem can be solved quite reliably in most instances. The degree of side dimorphism in bothid otoliths is not as great as in pleuronectids and in most instances is limited to details of the outline of the otolith. As stated before I have informally employed a division of the family Bothidae into two subfamilies – the Paralichthyinae and the Bothinae. In addition, it is possible, with the help of otolith analysis, to define at least 11 genus-groups exhibiting specific otolith morphologies. These are the Paralichthys, Pseudorhombus, Syacium, Citharichthys, Bothus, Arnoglossus, Monolene-Laeops, Engyprosopon, Thysanopsetta, Chascanopsetta and Mancopsetta Groups. The first four (Paralichthys, Pseudorhombus, Syacium and Citharichthys Groups) probably form a related cluster to which the subfamily status of Paralichthyinae may be attributed. This group is more or less equivalent to the Paralichthyinae of NORMAN (1934) and the Paralichthyidae of HENSLEY & AHLSTROM (1984). Their otoliths are relatively large, delicately ornamented, with a moderately to strongly reduced ostial opening. Furthermore, the Syacium and Citharichthys Groups exhibit a number of derived, presumably autapomorphic characters which makes their recognition relatively easy (see respective entries). HENSLEY & AHLSTROM Piscium Catalogus, Part Otolithi piscium, Vol. 2 (1984) recognized two generic groups, the Pseudorhombus and Cyclopsetta Groups (the latter including the Syacium and Citharichthys otolith groups). Likewise, the genera of the Bothus Group and the Arnoglossus, Monolene-Laeops and Engyprosopon Groups may be interrelated constituting the Bothinae of NORMAN (1934) (except for Trichopsetta, Engyophrys, Perissias and Monolene which he placed in the Paralichthyinae; in this latter respect the concept of the Bothidae of HENSLEY & AHLSTROM, 1984, agrees better with the otolith findings). The otoliths of these four bothine groups are relatively small in size, compact, often with a nearly rectangular outline with little ornamentation and with a full or only slightly reduced ostial opening. However, most of these characters except for the ostial opening must be regarded as somehow “reduced”. The remaining three groups – Thysanopsetta, Chascanopsetta and Mancopsetta Groups – stand somewhat apart from the rest of the Bothidae and, together with Tephrinectes, in my opinion are the first candidates for exclusion from the Bothidae proper (for details see respective entries and HENSLEY & AHLSTROM, 1984). For convenience only they are here kept in the subfamily Bothinae. In conclusion, the definition of the Bothidae by means of otolith morphology is not very satisfactory. Nevertheless, using otoliths, two large groups can be outlined which more or less reflect NORMAN’s classification of the two subfamilies Paralichthyinae and Bothinae and even more closely HENSLEY & AHLSTROM’s classification of the two families Paralichthyidae and Bothidae. In addition there are three small generic groups which stand somewhat isolated from the rest, and one genus – Tephrinectes – which clearly should be removed from the family. Distribution: Bothidae are widely distributed throughout the shallow seas of the world oceans. They are most common and specious in the tropical and subtropical latitudes. The two genera of the Mancopsetta Group are the only flatfishes occurring in Subantarctic and Antarctic waters. Some genera are caught in relatively deep water (Gastropsetta, Mancopsetta, Perissias, Thysanopsetta, Trichopsetta and certain species of Arnoglossus) on the lower continental shelf. The genera of the Chascanopsetta Group are amongst the deepest living flatfishes, usually caught on the continental rises. 106 Paralichthyinae 7.6.1 Paralichthys Group Genera: In this group I have placed 6 genera – Ancylopsetta, Gastropsetta, Hippoglossina, Xystreurys, Lioglossina and Paralichthys. This group is almost entirely from the new world, the exception being a single species of the genus Paralichthys (P. olivaceus from the coasts of China and Japan). Apart from two recent Paralichthys species recorded as fossils from the Pliocene of California and Japan, there are no fossil records of this group. Definition and relationship: Otoliths of the Paralichthys Group probably represent the most plesiomorphic condition within the Bothidae. Otoliths are moderately large, rather elongate and often nicely ornamented. The rostrum is always well developed. The sulcus opening is pseudoostial. The ostium is usually much longer than the cauda and sometimes slightly wider too. The cauda is short, straight and with a rounded termination. This “reduced” character constitutes the main difference from otoliths of the Scophthalmidae, which are otherwise quite similar. The circumsulcal depression is usually relatively feeble, but in most instances well connected behind the cauda. The degree of side dimorphism is very low, usually confined to minor differences in the outline of the otolith, if it is detectable at all. As a general rule the diagnostically critical size of otoliths of this group is reached between 3 and 4 mm. Total size rarely exceeding 8 mm. Morphologically, otoliths of the Paralichthys Group are somewhat intermediate between those of the Scophthalmidae and the more advanced bothid groups. Of the latter the Pseudorhombus, Syacium and Citharichthys seem to be most closely related. In ichthyological literature the two genera Paralichthys and Pseudorhombus are commonly regarded as very closely related (see NORMAN, 1934 and GINSBURG, 1952), to an extant that differentiation of the two genera becomes a very delicate task. Otoliths on the other hand are quite easily differentiated, although the close relationship may not be questioned. The reason for separating Pseudorhombus (and related genera) from the Paralichthys Group is principally based on the argument that their otolith analysis characterizes them as the basal morphology from which the other paralichthin groups may have derived (for detailed discussion see entries to genera Paralichthys, Pseudorhombus and the Pseudorhombus Group). Ancylopsetta GILL 1864 Type-species: Ancylopsetta quadrocellata GILL 1864 syn. Notosema GOODE & BEAN 1883 (type-species: Notosema dilecta) syn. Ranularia JORDAN & EVERMANN 1898 (type-species: Ancylopsetta dendritica) Diagnosis: Relatively thin, oval to elongate otoliths; ventral rim shallow and gently curving, deepest slightly posterior of the middle, dorsal rim with angular to rounded postdorsal angle and indistinct predorsal angle situated at about midventral position, posterior tip blunt or rounded, anterior rim with prominent rostrum, but without excisura; index l:h 1.45 to 1.85. Otolith size probably not much exceeding 5.5 mm. Ostium slightly wider than cauda but considerably longer, rather shallow. Index ol:cl 1.55 to 2.25. Ostial opening pseudoostial. Cauda short, straight with rounded termination at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions shallow, often indistinct, more or less well connected around caudal tip to form a circumsulcal depression. Inner face slightly convex; outer face slightly concave, flat or slightly convex, smooth to slightly ornamented. Rims sharp, smooth or slightly crenulated to irregularly undulating. Measurements: dilecta quadrocellata cycloidea microtenus antillarum l:h 1.45 1.80-1.85 1.70 1.70 1.55 h:t 3.1 3.7 nm 3.0 2.8 ol:cl 1.55 2.25 1.55 1.55 1.65 oh:ch 1.1 1.1-1.2 1.3 1.0 1.1 con.i about 4.0 about 4.5 nm about 5.0 about 6.0 Side dimorphism: Not apparent. Discussion: Otoliths of the genus Ancylopsetta are the least characteristic within this group due to their rather smooth and regularly curved outline. They closely resemble Lioglossina and certain Paralichthys species. Species and distribution: Ancylopsetta contains 7 recent species, 6 from the Atlantic coasts of Central and southern North America – A. antillaSchwarzhans: Pleuronectiformes 107 rum, A. cycloidea, A. dilecta, A. kumperae, A. microtenus and A. quadrocellata – and one from the Pacific coast of America from California to Panama – A. dendritica. a Ancylopsetta dilecta (GOODE & BEAN 1883) Fig. 166 c b syn. Paralichthys stigmatias GOODE 1884 Investigated otoliths: 1 otolith (right side) from off Carolina, USA (32°54’N/77°3’W), ZMH Ot. 20.3.1994.1 (leg USNM 45596). Discussion: This is the most compressed otolith found in all species of the Paralichthys Group with the most regularly rounded outline. A. dilecta thus is relatively easy to be recognized. The genus Notosema established for this species by GOODE & BEAN (1883) could possibly be regarded as a subgenus of Ancylopsetta. Distribution: Known only from the coasts of Carolina, USA. Fig. 166: Ancylopsetta dilecta (GOODE & BEAN 1883) – 10 × Discussion: Otoliths of A. quadrocellata are considerably more elongate than those of the other species investigated. They do resemble Paralichthys species with more rounded otolith outlines such as P. squamilentus and P. albiguttata. Both, however, show a relatively longer cauda as do most species of the genus Paralichthys. Distribution: Atlantic and Gulf coasts of the United States. Ancylopsetta cycloidea TYLER 1959 Fig. 169 Ancylopsetta quadrocellata GILL 1864 Figs. 167-168 syn. Paralichthys ommatus JORDAN & GILBERT 1879 Investigated otoliths: 2 otoliths (left and right side) from off Charleston, South Carolina, USA, ZMH Ot. 20.3.1994.2 (leg. BMNH 1933.8.10.13) and BMNH 1933.8.10.13. Investigated otoliths: 1 otolith (right side) from off Tobago, BMNH 1965.6.17.1. Discussion: The only specimen investigated is slightly damaged ventrally, but otherwise well preserved. It closely resembles A. quadrocellata except for the almost entirely smooth outline and the slightly lesser index l:h. Distribution: Caribbean. 167a 168 167c 167b Figs. 167-168: Ancylopsetta quadrocellata GILL 1864 – 10 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 108 a Fig. 169: Ancylopsetta cycloidea TYLER 1959 – 10x b Ancylopsetta microtenus GUTHERZ 1966 Fig. 170 Investigated otoliths: 1 otolith (right side), paratype, off Honduras, 16°5’N/81°7’W, BMNH 1965.6.17.6. Discussion: Very similar to A. cycloidea but less rounded in outline and with blunt posterior tip. Distribution: Off Honduras. Ancylopsetta antillarum BERRY & GUTHERZ 1965 Fig. 171 Investigated otoliths: 1 otolith (right side), paratype, NW Bahamas, 25°3’N/79°3’W, BMNH 1965.6.17.3. Discussion: Rather compressed, massive otolith with relatively flat ventral rim and pronounced dorsal rim. Distribution: Off Bahamas. Gastropsetta BEAN 1895 Type-species: Gastropsetta frontalis BEAN 1895 Diagnosis: Thin, fragile, moderately elongate otolith; ventral rim shallow and gently curving, dorsal rim more strongly bent with a pronounced, broadly rounded medioventral angle and a relatively feeble postdorsal angle, posterior tip rather blunt, anterior rim with massive, not very prominent rostrum and without excisura; index l:h 1.55. Otolith size about 3 mm. Fig. 170: Ancylopsetta microtenus GUTHERZ 1966 – 10 × Ostium slightly wider than cauda but considerably longer, rather shallow. Index ol:cl 2.9. Ostial opening pseudoostial. Cauda short, straight with rounded termination at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions very shallow to indistinct, but well connected around caudal tip to form a circumsulcal depression. Inner face slightly convex; outer face slightly concave, smooth to slightly ornamented. Rims sharp, slightly undulating. Measurements: frontalis l:h 1.55 h:t 4.3 ol:cl 2.9 oh:ch 1.5 con.i 4.8 Side dimorphism: Not known. Discussion: NORMAN (1934) regarded this genus as closely related to Ancylopsetta. This interpretation is supported by the habitus of the otolith in particular the very short cauda. In fact, it is the shortest cauda to be found within the Paralichthys Group. Gastropsetta may be regarded as a specialized off-branch from Ancylopsetta. NIELSEN (1963) described the new genus Dorsopsetta from off Peru, which he regarded as closely related to Gastropsetta (otoliths of that genus are not known). Species and distribution: Gastropsetta is a monotypic genus. Its only species G. frontalis has been caught very rarely in relatively deep water off Florida, USA. NORMAN (1934) has recorded only three catches of this species. Schwarzhans: Pleuronectiformes 109 a a c b b Fig. 172: Gastropsetta frontalis BEAN 1895 – 15 × Fig. 171: Ancylopsetta antillarum BERRY & GUTHERZ 1965 – 10 × Gastropsetta frontalis BEAN 1895 Fig. 172 Investigated otoliths: 1 otolith (left side) from off dry Tortugas, Florida, USA, BMNH 1933. 10.12.125. Discussion: See entry to genus (monotypic genus). Distribution: In relatively deep water off Florida, USA. [Dorsopsetta NIELSEN 1963] Type-species: Dorsopsetta norma NIELSEN 1963 Remarks: Dorsopsetta was erected as a monospecific genus by NIELSEN, known only from two relatively small subadults caught off Peru. The paratype in the ZMUC collection (P 853116) has been x-rayed in order to find out whether otoliths are still preserved. Unfortunately, they were not, probably dissolved by formalin. NIELSEN regarded Dorsopsetta als related to Gastropsetta. In the meantime D. norma has been reviewed by HEIDEN & PEREZ (1993). They regarded NIELSEN’s type-specimens as a synonym of Cyclopsetta querna (see respective entry). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Hippoglossina STEINDACHNER 1876 Type-species: Hippoglossina macrops STEINDACHNER 1876 Diagnosis: Relatively thin, elongate otoliths; ventral rim shallow and gently curving, deepest slightly posterior of the middle, dorsal rim likewise shallow with rounded pre- and postdorsal angles, posterior tip obtuse or rounded, anterior rim with moderately strong and blunt rostrum, but without excisura; index l:h 1.70 to 1.85. Otolith size probably not much exceeding 7 mm. Ostium slightly wider than cauda but not very much longer, slightly deepened. Index ol:cl 1.4 to 1.8. Ostial opening pseudoostial. Cauda not very short, straight to just very slightly curving, with rounded termination at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions rather well developed, but connection around caudal tip often feeble or indistinct. Inner face almost flat; outer face slightly convex, smooth. Rims sharp, smooth or slightly and irregularly undulating. Measurements: macrops (left) macrops (right) stomata (left) stomata (right) l:h 1.70-1.80 2.8 1.80-1.85 2.8 h:t 3.5 3.4 ol:cl 1.8 1.45 1.4 oh:ch 1.0-1.1 1.1-1.2 con.o about 7.0 about 3.5 about 5.5 about 4.5 Side dimorphism: Side dimorphism in otoliths of this genus is rather feeble or so tends to submerge under the relatively high degree of variability. The latter is particularly true for the proportions and outline of otoliths and sulcus. How- 110 Hippoglossina to be even more closely related to Pseudorhombus. This view, however, is decidedly contradicted by the otolith analysis (see also entries to Pseudorhombus and Pseudorhombus Group). a b Species and distribution: GINSBURG (1952) mentioned four species of the genus Hippoglossina, all of them restricted to the Pacific shores of America (from California to southern Chile) – H. bollmani, H. macrops, H. mystacium and H. stomata. CHIRICHIGNO (1974) lists a fifth species from southern Peru and Chile – H. montemaris. Fig. 173: Hippoglossina aff. macrops STEINDACHNER 1876 – fig. 173a = 15 ×; fig. 173b = 10 × Hippoglossina aff. macrops STEINDACHNER 1876 Fig. 173 ever, some degree of side dimorphism seems to be stable as far as width of the sulcus (narrower in left otoliths) and convexity of outer face (more convex or thickset in right otoliths) is being concerned. Investigated otoliths: 2 otoliths from 1 specimen (left and right side) from the Smyth Channel, Magellan Strait, ZMH Ot. 20.3.1994.3-4 (leg. ZMH 19958). Variability: Details of the outline of the otoliths as well as its proportions and the proportions of the sulcus seem to be quite variable. As a result of this distinction of the closely related species may not always be possible. Discussion: Hippoglossina otoliths can be distinguished from other genera of the Paralichthys Group by at least three major characters. They show the proportionally longest cauda which in some instances even exhibits a faint curvature. This is supposed to be an inherited plesiomorphic character. Secondly, the inner face is unusually flat. Thirdly, the otoliths are quite elongate, but this is not due to a long rostrum but the overall elongate shape of the otolith. The two latter are regarded as apomorphic features. NORMAN (1934) has related Hippoglossina to Lioglossina and Paralichthys and also regarded Hippoglossina as one of the most plesiomorphic genera in his Paralichthyinae. Indeed does the structure of the cauda exhibit a comparatively more primitive nature, but the other characters as listed above do not. A close relationship to Lioglossina and Paralichthys may very well be the case, but according to otolith analysis I would then regard Hippoglossina as an early somewhat specialized off-shot from the main Paralichthin branch. GINSBURG (1952) stated that he found Remarks: These otoliths were obtained from one of two specimens recorded by LÖNNBERG (1907). According to GINSBERG (1952) the specific assignment of the two specimens is questionable, particularly since the origin of STEINDACHNER’s holotype is unclear. NORMAN (1934) describes the two specimens of GÜNTHER as representing H. macrops which originated from the same region (Magellan Strait) as the one LÖNNBERG specimen from which I have taken otoliths. Later (1937) he placed the two GÜNTHER specimens in H. mystacium. In GINSBURG’s recommendations the two LÖNNBERG specimens need restudy before a definite conclusion about their specific allocation can be reached. Preliminarily, I have chosen to leave the specimen in question and from which the otoliths have been obtained with H. macrops, following LÖNNBERG’s original identifications. Discussion: The otoliths of H. aff. macrops are very similar to those of H. stomata. If there are any diagnostically valid and stable differences they are probably the more bluntly developed posterior rim in H. aff. macrops and also its slightly lesser index l:h. Anyway, the specimens investigated from H. stomata and H. aff. macrops have been obtained at the northern and southern limits of the distribution pattern of this genus and thus sheds some light on the poor level of morSchwarzhans: Pleuronectiformes 111 174 175a 175b 175c 176a 176b Figs. 174-176: Hippoglossina stomata EIGENMANN & EIGENMANN 1890 – figs. 174, 175a, 176a = 15 ×; figs. 175b,c 176b = 10 × phological differentiation to be expected from the otoliths of its species. If I interpret GINSBERG’s remarks correctly the same may be true as well for other “more traditional” taxonomic methods. Distribution: The type location of the species given by STEINDACHNER was Mazatlan (northern Mexico, Pacific coast), which falls in the distribution range of H. stomata. NORMAN (1934) concluded that the type locality given by STEINDACHNER was almost certainly incorrect. Then H. macrops should be distributed only along the shores of Chile as far south as the Magellan Strait. Hippoglossina stomata EIGENMANN & EIGENMANN 1890 Figs. 174-176 Investigated otoliths: 4 otoliths, 3 figured (left and right side) from off Acapulco, Pacific coast of central Mexico, ZMH Ot. 20.3.1994.5-8 (leg. Fitch). Variability: The two specimens figured already show the relatively large degree of variability to be expected within the species of this genus. Features concerned are ornamentation of the outline (smooth or undulating), proportions of the otoPiscium Catalogus, Part Otolithi piscium, Vol. 2 lith (index l:h) and development of the angles at the dorsal rim. Discussion: Otoliths of H. stomata are hardly to distinguished from those of H. aff. macrops (see respective entry). Distribution: California, USA and Pacific coast of Mexico. Xystreurys JORDAN & GILBERT 1881 Type-species: Xystreurys liolepis JORDAN & GILBERT 1881 syn. Verecundum JORDAN 1890 (type-species: Verecundum rasile) Diagnosis: Thin, elongate otoliths; ventral and dorsal rims shallow and gently curving, dorsal rim with indistinct and rounded pre- and postdorsal angles, posterior tip blunt or obtuse, anterior rim with moderately pronounced rostrum, but without excisura; index l:h 1.75 to 1.8. Otolith size of specimens investigated about 5 mm. Sulcus narrow. Ostium not or only slightly wider than cauda and not very much longer, rather shallow. Index ol:cl 1.45 to 1.65. Ostial opening 112 177 178a 178c 178b 179 Figs. 177-179: Xystreurys liolepis JORDAN & GILBERT 1881 – 10 × pseudoostial. Cauda moderately short, straight with rounded termination at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions well marked, faintly connected around caudal tip to form a circumsulcal depression. Inner face slightly convex; outer face slightly concave and slightly ornamented. Rims sharp, delicately undulating. Xystreurys liolepis JORDAN & GILBERT 1881 Figs. 177-179 Investigated otoliths: 3 otoliths from off California USA, (2 left and 1 right side) ZMH Ot. 20.3.1994.10-11 (leg. BMNH 91.5.19.169-170) and BMNH 91.5.19.169-170. Discussion: See entry to X. rasile. Measurements: liolepis rasile l:h 1.75-1.80 1.75-1.80 h:t 4.8 4.1 ol:cl 1.45-1.65 1.8-1.85 oh:ch 1.0-1.1 1.1 con.i about 6.5 about 10 Side dimorphism: Not apparent. Variability: The variability seems to be unusually small, except for the intensity of the marginal ornamentation observed in X. liolepis, particularly so at the posterior rim. Discussion: The otoliths of the genus Xystreurys resemble those of Hippoglossina in outline. Species and distribution: Two recent species, one – X. liolepis – from southern California, USA, the other – X. rasile – from Brazil to Argentine. Distribution: Coast of California, USA. Xystreurys rasile (JORDAN 1890) Figs. 180-181 syn. Hippoglossina notata BERG 1895 syn. Xystreurys brasiliensis REGAN 1914 Investigated otoliths: 2 otoliths (right side) from off Uruguay, ZMH Ot. 2.1.1995.9 (leg. BMNH 1935.9.11.10-11) and BMNH 1935.9.11.10-11. Discussion: Similar to X. liolepis but without marginal crenulation and with rather strongly developed predorsal angle. Also the cauda is somewhat shorter (index ol:cl). Distribution: Coasts of Brazil, Uruguay and Argentine. Schwarzhans: Pleuronectiformes 113 181a 180 181b Figs. 180-181: Xystreurys rasile (JORDAN 1890) – 10 × Lioglossina GILBERT 1891 Type-species: Lioglossina tetrophthalmus GILBERT 1891 Diagnosis: Moderately thin and moderately elongate otoliths; ventral rim shallow and gently curving, deepest slightly posterior of the middle, dorsal rim relatively high and also regularly curving with faint postdorsal angle and very indistinct predorsal angle, posterior tip rounded, anterior rim with prominent rostrum, but without excisura; index l:h 1.55 to 1.75. Otolith size probably not exceeding much 5-6 mm. Ostium not or only slightly wider than cauda but considerably longer, rather shallow. Index ol:cl 1.75 to 2.9. Ostial opening pseudoostial with tendency for further reduction. Cauda short, straight with rounded termination at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions moderate, faintly connected around caudal tip to form a circumsulcal depression. Inner face slightly convex, more strongly so in the vertical direction; outer face more or less flat, slightly ornamented. Rims sharp, intensely to very intensely ornamented. Measurements: tetrophthalmus (l) tetrophthalmus (r) oblongus (r) l:h 1.75 1.65 1.55 h:t 3.5 4.3 ol:cl 2.9 1.8 1.75 oh:ch 1.1-1.2 con.i about 8.0 1.0 about 9.0 Side dimorphism: Development of side dimorphism is relatively feeble, as seen in one of the two species (L. tetrophthalmus). It seems that the left otoliths have a slightly more pronounced Piscium Catalogus, Part Otolithi piscium, Vol. 2 rostrum, which also finds its expression in the index l:h. As a consequence the ostium is also longer in the left otolith which account for at least half of the unusually high index ol:cl. Ontogeny: The otoliths examined of the two species are still relatively small and may not have developed all pertinent diagnostic features, although it seems that at least the one from L. oblongus is quite characteristic (5 mm length). Discussion: NORMAN (1934) and GINSBURG (1952) both had Lioglossina as closely related to Hippoglossina and Paralichthys. This is confirmed by otoliths, although from their analysis Lioglossina seems to be more closely related to Paralichthys than Hippoglossina. In fact, Lioglossina could well represent a specialized off-shot from Paralichthys. The high dorsal rim and the tendency to reduce the ostial opening are seen as the major differences to Paralichthys otoliths. NORMAN (1934) regarded Lioglossina as a monotypic genus with L. tetrophthalmus being its only species. GINSBURG (1952) also included L. oblonga. I have followed his view, although the status of investigation of otoliths from L. tetrophthalmus at present is not really adequate (see also to species). Species and distribution: Two species – L. tetrophthalmus known from the Gulf of California and Pacific coast of Central America (the specimen from which the otolith were obtained was caught at the Pacific coast of Columbia) and L. oblonga from the Atlantic coast of North America from Massachusetts to Florida. 114 182a 183 182b 182a Figs. 182-183: Lioglossina tetrophthalmus GILBERT 1891 – 15 × Lioglossina tetrophthalmus GILBERT 1891 Figs. 182-183 Investigated otoliths: 2 otoliths from 1 specimen (left and right side) from the Pacific coast of Columbia (3°44’N/77°32’W), SMF unreg. (1 now ZMH Ot. 20.3.1994.9). Discussion: Otoliths of L. tetrophthalmus are more “Paralichthys alike” than those of the other species of the genus – L. oblonga. The latter differs in the more reduced ostial opening and the very high dorsal rim with its extremely strong ornamentation. Distribution: Pacific coast from California to Middle America. The specimen figured was tak- en from a fish caught at the Pacific coast of Columbia, which is south of the distribution limits noted by NORMAN (1934) and GINSBURG (1952). Lioglossina oblonga (MITCHILL 1815) Fig. 184 Investigated otoliths: 1 otolith (right side) from off New Jersey, USA (40°10’N / 73°36’W), BMNH 1923.6.18.2. Discussion: Otoliths of this species are readily distinguished from other species in the Paralichthys Group by the high dorsal rim, which is very intensely ornamented, and the reduced ostial opening. The whole sulcus is relatively small and narrow. Distribution: Atlantic coast of North America from Massachusetts to Florida. Paralichthys GIRARD 1858 Type-species: Pleuronectes maculosus GIRARD 1856 (preoccupied) – syn. Paralichthys californicus a c b syn. Chaenopsetta GILL 1861 (type-species: Pleuronectes dentatus – see GINSBURG 1952) syn. Uropsetta GILL 1863 (type-species: Hippoglossus californicus) Fig. 184: Lioglossina oblonga (MITCHILL 1815) – 10 × Schwarzhans: Pleuronectiformes 115 Diagnosis: Relatively thin, moderately elongate to elongate otoliths; ventral rim shallow and gently curving, dorsal rim variable, usually with pronounced postdorsal and less well developed predorsal angles, posterior tip blunt or rounded sometimes with obtuse angle, anterior rim with prominent to very prominent rostrum, but usually without excisura; index l:h ranging from 1.55 to 2.05. Otolith size probably not much exceeding 8 mm. Ostium usually slightly wider than cauda and considerably longer, rather shallow. Index ol:cl ranging from 1.45 to 2.20, rarely up to 2.85. Ostial opening pseudoostial. Cauda short, straight with rounded termination at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions usually well marked, more or less well connected around caudal tip to form a circumsulcal depression. Inner face slightly to moderately convex; outer face slightly concave to flat, smooth to slightly ornamented. Rims sharp, smooth or variably ornamented. Measurements (ab.=about): l:h orbignyana 1.60 dentatus 1.55-1.65 albiguttata 1.80 squamilentus 1.75 lethostigma 1.70 tropicus 2.00 brasiliensis 1.95 californicus 1.70-1.85 adspersus 1.65 microps 1.75-1.85 olivaceus 1.85 isocles 1.55 h:t 3.0 3.2 3.2 3.2 3.9 2.5 3.2 3.4 3.7 3.4 2.9 2.7 ol:cl 1.60-1.85 1.65 1.45-2.00 2.00 1.85 1.70 1.50 2.0-2.1 1.65-1.8 1.80-1.85 2.2-2.3 2.4-2.85 oh:ch con.i 1.05-1.6 ab. 4.0 1.1-1.2 ab. 5.5 1.2-1.3 ab. 5.5 1.25 ab. 4.3 1.15 ab. 5.0 1.35 ab. 4.0 1.2 ab. 4.2 1.45-1,55 ab. 6.0 1.2-1.25 ab. 7.0 1.25-1.5 ab. 8.0 1.1-1.2 ab. 5.0 1.05-1.25 ab. 15.0 Side dimorphism: Side dimorphism is poorly developed in this genus and there are some species which do not show any asymmetry at all. Characters affected are exclusively those of the outline of the otolith, in particular length and expression of the rostrum, angles at the dorsal rim and expression of the posterior rim. Ontogeny and variability: Ontogenetic changes can only be studied in P. californicus and P. olivaceus. From this it appears that smaller specimens exhibit a much more rounded and more generalized outline than larger ones and sometimes are also more strongly ornamented along its margins, but in a less regular fashion. It seems that the critical size at which all pertinent characters are being developed is of considerable importance in Piscium Catalogus, Part Otolithi piscium, Vol. 2 this genus. It seems that in P. californicus this size is reached with otoliths of about 5 mm of length. In P. olivaceus that size is reached at about 6 mm. However, this is one of the largest growing species within the genus. There are indications from other, smaller species that the critical size may commonly been reached somewhere between 4 and 5 mm of length. Variability on the other hand seems to play a less important role in this genus once the critical size is being reached. In general it is restricted to details of the outline and proportions of the sulcus, but seemingly never reaches the amount observed in so many other Pleuronectiform otoliths. Discussion: Otoliths of the genus Paralichthys are quite easily recognized by their typical outline including the strongly developed rostrum and the pattern of their sulcus. Distinction of isolated otoliths from some of the related genera, namely Ancylopsetta and Lioglossina, however, may not always be easy. Otoliths of the genus Pseudorhombus, which is thought to be closely related to Paralichthys, are readily differentiated by their strongly reduced rostrum and their peculiar outline. There are certain Pleuronectid otoliths which also bear some basal similarity, particularly in the Hippoglossus and the Pleuronectes-Limanda Groups. These similarities in the overall habitus of the otoliths are probably due to synplesiomorphies. The Paralichthys and the Hippoglossus Groups are thought to represent the most plesiomorphic groups within their respective families (Bothidae and Pleuronectidae). However, otoliths of the two Pleuronectid groups mentioned are in most instances easily recognized by their more strongly reduced ostial opening and the much wider and more clearly developed circumsulcal depression. Also the colliculi are usually more deepened. GINSBURG (1952) has proposed to subdivide the genus Paralichthys into two subgenera, namely Paralichthys and Chaenopsetta. However, his subdivision can not be verified by otolith findings. Although otolith analysis could be used to point out certain species which may be more closely related to each other than others, the differentiation at this stage in my opinion is to vaguely to cluster them in species groups or even subgenera. However, the somewhat isolated position of P. isocles is well supported by otolith analysis. This species differs from all the others by its quite thickset appearance, the relatively flat 116 185a 185c 186 185b Figs. 185-186: Paralichthys orbignyana JENYNS 1842 – 10 × inner face, the very short cauda and the more strongly deepened sulcus with its tendency to fused colliculi. GINSBURG (1952) placed this species into the genus Pseudorhombus which would make it the only representative of that genus in the new world. The presence of a well developed rostrum in my opinion still warrants its placement in Paralichthys or may be a separate genus close to Paralichthys. Remarks: In a monograph dealing with the species of genus Paralichthys GINSBERG (1952) pointed out the difficulties in safely distinguishing several of them. From his list of synonymies it appears that many species have been confused in the past and even his excellent review is not free of remaining open questions as to the exact nomenclature of some species. In this light the Paralichthys otoliths discussed and figured in the following must be viewed with some care. It is possible that few specimens from which otoliths have been obtained were misidentified. Most of the BMNH material probably was identified by NORMAN. Other otoliths were extracted from fishes in the ZMH collection which most likely still bear their original labels irrespective of NORMAN’s and GINSBURG’s works. The identification of these otoliths may be found less reliable. Species and distribution: In combining NORMAN’s and GINSBURG’s works at least 17 species of the genus Paralichthys may tentatively be regarded as valid. They are: Atlantic coast of America: P. aestuarius, P. albiguttata, P. brasiliensis, P. dentatus, P. isocles, P. lethostigma, P. orbignyana, P. squamilentus, P. tropicus; Pacific coast of America: P. adspersus, P. californicus, P. fernandezianus, P. hilgendorfi, P. microps, P. schmitti, P. woolmani; Coasts of China and Japan: P. olivaceus. In addition there are some doubtful species such as P. triocellatus from the South Atlantic and P. caeruleosticta from Juan Fernandez Island off Chile. P. bicyclophorus from the South Atlantic was regarded as a valid species by NORMAN but as a synonym of P. orbignyana by GINSBURG. P. vorax was regarded as a valid species by GINSBURG but as a synonym of P. brasiliensis by NORMAN. Several of these species have been described by a single holotype such as P. bicyclophorus, P. triocellatus, P. caeruleosticta, P. fernandezianus, P.hilgendorfi and P. schmitti. The last four were all described from the small Juan Fernandez Island of Chile. This fact alone renders some doubt as to the validity of so many species in such an isolated and restricted geographic situation. Of course, otoliths of these species have not been available for investigation. Paralichthys orbignyana JENYNS 1842 Figs. 185-186 syn. Paralichthys patagonicus JORDAN & GOSS 1889 (according to GINSBURG, 1952) ?syn. Paralichthys bicyclophorus RIBEIRO 1915 (according to GINSBURG, 1952) Investigated otoliths: 2 otoliths from one specimen (left and right side) from off Rio Grande do Sul, southern Brazil, ZMH Ot. 20.3.1994.12 (leg. BMNH 85.2.3.73-74) and BMNH 85.2.3.73-74. Side dimorphism: The right hand otolith seems to have a slightly more pointed and elongate rostrum. Schwarzhans: Pleuronectiformes 117 187a 185b 187c 188a 187b Figs. 187-188: Paralichthys dentatus (LINNAEUS 1766) – 10 × Discussion: Otoliths of P. orbignyana are quite easily recognized by their relatively compressed shape, which includes a deeply curved ventral rim and a relatively short rostrum and the feeble development of the postdorsal angle. Also the rims are smooth without much of an ornamentation. In outline and habitus P. squamilentus and P. albiguttata are similar, but their otoliths are more elongate. The same is true for P. lethostigma which also shows a shorter cauda. P. dentatus is similarly compressed as P. orbignyana, but sulcus and in particular cauda are wider and the postdorsal angle is much more strongly developed. Distribution: Southern Atlantic, coasts from Brazil to Argentina. Paralichthys dentatus (LINNAEUS 1766) Figs. 187-188 syn. Pleuronectes melanogaster MITCHILL 1825 syn. Platessa ocellaris DE KAY 1842 syn. Paralichthys ophyras JORDAN & GILBERT 1883 Investigated otoliths: 2 otoliths from one specimen (left and right side) from off Long Island, USA, ZMH Ot. 20.3.1994.13-14 (leg. ZMH 19971). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: The right hand otolith shows a much shorter rostrum and a more pointed posterior tip. Discussion: Otoliths of P. dentatus are rather compressed. In this respect they resemble P. orbignyana and P. adspersus. P. orbignyana shows a more gently curving dorsal rim and a narrower sulcus; P. adspersus exhibits a more strongly protruding postdorsal angle and a less convex inner face. Distribution: Atlantic coast of North America, from Maine to Florida. Paralichthys albiguttata JORDAN & GILBERT 1883 Figs. 189-190 Investigated otoliths: 2 otoliths from one specimen (left and right side) from of SW-Florida, USA, ZMH Ot. 20.3.1994.15 (leg. BMNH 1930.8.6.1-2) and BMNH 1930.8.6.1-2. Side dimorphism: Not apparent. Discussion: Otoliths of P. albiguttata are easily recognized by the combination of an elongate shape and a rather regularly curving outline with- 118 190a 189 190c 190b Figs. 189-190: Paralichthys albiguttata JORDAN & GILBERT 1883 – 10 × out any prominent angles at the dorsal rim. P. albiguttata is a relatively small species of this genus and it is therefore assumed that this morphology represents a true adult type. However, distinction of subadult otoliths of other Paralichthys species may not always be easy (see also P. squamilentus). Distribution: South Atlantic and Gulf coast of the United States. Paralichthys squamilentus JORDAN & GILBERT 1883 Fig. 191 Investigated otoliths: 1 otolith (right side) from off Port Arkansas, Texas, USA, BMNH 1948. 8.6.1223. Discussion: This otolith of P. squamilentus in all respects closely resembles the one from P. albiguttata. Distinction of the two is almost impossible. However, as said before, certain doubts may remain as far as the correct identification of the species is concerned. Also P. squamilentus is known to grow to larger sizes than P. albiguttata. Therefore, the single specimen available from that species may not necessarily exhibit all valid diagnostic features. Distribution: South Atlantic and Gulf coast of the United States. Paralichthys lethostigma JORDAN & GILBERT 1885 Figs. 192-193 Investigated otoliths: 2 otoliths, one (right side) from of North Carolina, USA, BMNH 1923.12. 18.11. Discussion: The otoliths of P. lethostigma probably represent subadults since this is known as one of the largest species of the genus. Its irregular marginal crenulation indeed suggests that not all pertinent diagnostic features are yet developed (see also to P. olivaceus). Otherwise, P. lethostigma resembles both P. albiguttata and P. squamilentus in general appearance. It can be distinguished in being thinner and exhibiting a more pronounced postdorsal angle. a b Fig. 191: Paralichthys squamilentus JORDAN & GILBERT 1883 – 10 × Distribution: Atlantic coast of America, from New York to Trinidad. Schwarzhans: Pleuronectiformes 119 192a 193a 192b 193b Figs. 192-193: Paralichthys lethostigma JORDAN & GILBERT 1885 – 10 × Paralichthys tropicus GINSBURG 1933 Fig. 194 Paralichthys brasiliensis (RANZANI 1840) Fig. 195 Investigated otoliths: 1 otolith (right side) from off British Guiana, BMNH 1984.8.8.327. syn. Rhombus aramaca CASTELNAU 1855 ?syn. Pseudorhombus vorax GÜNTHER 1862 Discussion: This large and surely adult otolith of P. tropicus is readily recognized by its very elongate shape. Dorsal and ventral rims are both shallow. The predorsal angle is almost more strongly developed than the postdorsal angle and the posterior tip of the otolith is developed to a protruding, massive projection. The only similar species is P. brasiliensis (see respective entry). P. squamilentus and P. albiguttata are somewhat similar as well, but not quite as elongate and without the protruding posterior tip. Investigated otoliths: 1 otolith (right side) without mentioning of a location, ZMH Ot. 20.3.1994.16 (leg. ZMH 19966). Distribution: Tropical Atlantic, from Trinidad and Guiana. a b Fig. 194: Paralichthys tropicus GINSBERG 1933 – 10 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: The only available otolith exhibits a truly mature morphology. It is as elongate as P. tropicus and mainly differs in being more thin, exhibiting a more slender rostrum and a deep incision at the posterior rim just above the projecting posterior tip. This posterior tip is not as massively and as protrudingly developed as in P. tropicus. Nevertheless, the two otoliths could well represent variations of only one species. a b Fig. 195: Paralichthys brasiliensis (RANZANI 1840) – 10 × 120 197c 196 197a 197b 199 198 Figs. 196-199: Paralichthys californicus (AYRES 1862) – 10 × Distribution: Atlantic coast of South America, from southern Brazil to Patagonia. Paralichthys californicus (AYRES 1862) Figs. 196-199 syn. Pleuronectes maculosus GIRARD 1856 (preoccupied) Investigated otoliths: 6 otoliths from 3 specimens (left and right side) from off California, USA, ZMH Ot. 20.3.1994.17-22 (leg. Fitch). Ontogeny and variability: The smallest otolith (fig. 199), which is about half the size of the largest (fig. 196), shows a much more regularly curving outline. In particularly the postdorsal angle and the rostrum are not nearly as strongly developed as in the larger otoliths. Variability on the other hand seems to be very restricted. Side dimorphism: Apparently in left hand otoliths the sulcus is somewhat deeper and the separation of the colliculi has almost disappeared. Schwarzhans: Pleuronectiformes 121 201 200a 200b Figs. 200-201: Paralichthys aff. adspersus (STEINDACHNER 1867) – 10 × Discussion: P. californicus has moderately elongate otoliths which are characterized by a very sharp and angular postdorsal angle in combination with an almost vertically cut posterior rim. These are the main differences to P. tropicus and P. brasiliensis. More similar are P. microps, P. adspersus and P. olivaceus. P. microps shows a more regularly curved ventral rim, a very long and massive rostrum and rather smooth rims. P. adspersus is more compressed and with a much smaller index ol:cl. P. olivaceus probably comes closest, but its otoliths are more strongly and irregularly ornamented and the posterior rim is not really vertically cut. Finally, P. lethostigma could prove to have similar otoliths as well, once truly adult otoliths of this species have been investigated. Distribution: Coasts of California, USA and northern Mexico. P. californicus is also known as fossil from the Upper Pliocene and Pleistocene of California. Paralichthys aff. adspersus (STEINDACHNER 1867) Figs. 200-201, 15 allocation or specific identification must be erroneous. After having correlated the otoliths with those of a supposedly well identified P. dentatus (see above) I have concluded that it is possibly the identification that is wrong. Along the shores of Chile there are two Paralichthys species – P. microps and P. adspersus. Otoliths of P. microps again are quite different, leaving P. adspersus as a logical alternative. However, the specific assignment must be regarded as tentative only until the fish itself has been re-examined. Side dimorphism: The left hand otolith exhibits a somewhat deeper sulcus and less clearly separated colliculi. Discussion: The outline of these otoliths closely resemble P. microps and P. californicus in the long and pointed rostrum, the strong and nearly rectangular postdorsal angle and the vertically cut posterior rim. However, the otoliths of P. aff. adspersus are more compressed and have a lesser index ol:cl. Distribution: Coasts of Peru and Chile. Paralichthys microps (GÜNTHER 1881) Figs. 202-204 ?syn. Hippoglossus kingii JENYNS 1842 syn. Paralichthys jordani STEINDACHNER 1898 Investigated otoliths: 2 otoliths from 1 specimen (left and right side) from off Coronel, Chile, ZMH 20.3.1994.23-24 (leg. ZMH 19970, identified as P. dentatus). Remarks: The specimen, from which this otolith has been taken, was labeled as P. dentatus from Chile. This label does not fit with the distribution pattern of P. dentatus. Therefore, either geographic Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 4 otoliths from 3 specimens (1 left and 3 right side) from the coast of Chile, ZMH Ot. 20.3.1994.25-27 (BMNH 1935.4.23.63-66) and BMNH 1935.4.23.63-66. Variability: The variability within this species is quite restricted to details of the dorsal and posterior rims. 122 203a 202a 203b 203c 202b 202c 204 Figs. 202-204: Paralichthys microps (GÜNTHER 1881) – 10 × Side dimorphism: Not apparent. Discussion: Otoliths of P. microps are quite characteristic. They are easily recognized by their gently and regularly curving ventral rim, the blunt posterior tip, the very long and massive rostrum, the thin appearance and the rather flat inner face. They belong to the more elongate species in this genus. Distribution: Coasts of Chile. Paralichthys olivaceus (TEMMINCK & SCHLEGEL 1846) Figs. 205-206 syn. syn. syn. syn. Rhombus wolffii BLEEKER 1854 Platessa percocephala BASILEWSKY 1855 Pseudorhombus swinhonis GÜNTHER 1873 Paralichthys coreanicus SCHMIDT 1904 Investigated otoliths: 2 otoliths, 1 large specimen (right side, fig. 205) from off China, ZMH Ot. 20.3.1994.28 (leg. BMNH 84.2.26.44), and 1 smaller specimen (right side, fig. 206) from Toyama, Japan, BMNH 1933.6.12.1. Ontogeny: The smaller otolith is more generalized, less characteristic in outline and also much more strongly crenulated along its rims. P. olivaceus obviously is one of the larger species within this genus and the diagnostically critical size is only reached at about an otolith length of 6 mm. Discussion: P. olivaceus is quite similar to P. californicus merely differing in the stronger ornamentation of the otolith rims and in the less bluntly developed posterior rim. Distribution: P. olivaceus is the only species of this genus which occurs outside the new world. It is known from the shores of China, Japan and Korea. It has also been obtained as fossil from the Pliocene of Japan (OHE, 1981; as Arnoglossus aff. laterna). Paralichthys isocles JORDAN 1890 Figs. 207-208 Investigated otoliths: 2 otoliths from 1 specimen (left and right side) from the Discovery station W.S. 852 and 788, ZMH Ot. 20.3.1994.29 (leg. BMNH 1936.8.26.1221-3) and BMNH 1936.8.26. 1221-3. Schwarzhans: Pleuronectiformes 123 206b 205 206a 206c 207 208b 208a 208c Figs. 205-206: Paralichthys olivaceus (TEMMINCK & SCHLEGEL 1846) – 10 × Figs. 207-208: Paralichthys isocles JORDAN 1890 – 10 × Side dimorphism: Separation of the colliculi is less well developed in the left hand specimen and also the cauda is considerably shorter. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Otoliths of P. isocles somewhat stand apart from other species in the genus. They are characterized by the thickset appearance, the relatively flat inner face, the very short cauda and the more strongly deepened sulcus. GINSBURG 124 (1952) felt that it should be placed in the genus Pseudorhombus. However, the massive although not very long rostrum contradict such a generic allocation. In my opinion the species represents a specialized off-shot from Paralichthys rather than a Pseudorhombus species. Eventually, it might best be placed into a genus of its own. Distribution: Atlantic coast of North America, from Brazil to northern Argentina. 7.6.2 Pseudorhombus Group Genera: Two genera are placed in this group – Pseudorhombus and Tarphops – and a third genus – Cephalopsetta – of which otoliths are not known, is tentatively associated as well. The geographic distribution of this group is confined to the IndoPacific. However, there is also one good fossil record of the genus Pseudorhombus from the Miocene of Europe (Austria, Paratethys). Definition and relationship: Otoliths of the Pseudorhombus Group are easily recognized by the combination of the following characters. The rostrum is more or less completely reduced and the ostial opening of the sulcus is somewhat reduced as well. The outline of the otolith is characterized by a massively developed predorsal projection and also an often similarly massive postventral angle. The resulting shape of the otolith resembles a rectangle. When oriented in the traditional way, which means horizontal to the more or less straight and parallel dorsal and ventral rims, the sulcus appears to be inclining anteriorly. The sulcus itself is divided into a longer ostium and an ovally shaped cauda which is of about half the length of the ostium. The sulcus is widest at about midpoint, equaling the posterior portion of the ostium. This character is interpreted as an incipient stage towards the “fusiform sulcus structure” observed in the Syacium and Citharichthys Groups. The circumsulcal depression is usually well developed. The size of the otoliths is relatively small, rarely surpassing 4 mm in length. Specimens of about 2 to 2.5 mm length generally have developed all pertinent and diagnostically valid features. Side dimorphism is mild, usually confined to slight differences in the outline of the otolith and separation of the colliculi. In ichthyological literature (see for instance NORMAN, 1934) Pseudorhombus is generally considered to be closely related to Paralichthys of the Paralichthys Group. Even defining the generic boundaries between the two genera seems to be problematical in some instances. With otoliths the separation is quite clear. The reduced, practically absent rostrum and the peculiar outline of Pseudorhombus otoliths define this genus quite reliably. However, few transitional morphologies do exists (see entry to Pseudorhombus) and thus confirm the apparent relationship of the two genera. However, I have selected to place Pseudorhombus in a different otolith group, because it likely represents the starting point for the evolution of the highly specialized otolith morphologies found in the related Syacium and Citharichthys Groups (see respective entries). Also the small and compact otoliths of the Bothus and the Arnoglossus-Monolene Groups (more or less equaling the Bothinae of NORMAN) exhibit some basal resemblance to Pseudorhombus otoliths, at least as far as the almost rectangular outline is concerned. I do not consider these two groups of being particularly closely related to the Pseudorhombus Group or its derivatives, but it is quite possible that their otolith morphology had developed along similar patterns. Pseudorhombus BLEEKER 1862 Type-species: Rhombus polyspilus BLEEKER 1853 (syn. P. arsius) ?syn. Neorhombus CASTELNAU 1875 (type-species: Neorhombus unicolor) syn. Teratorhombus MACLEAY 1882 (type-species: Teratorhombus excisiceps, syn. P. arsius) syn. Rhombiscus JORDAN & SNYDER 1901 (type-species: Rhombus cinnamoneus — subgenus) syn. Spinirhombus OSHIMA 1927 (type-species: Spinirhombus ctenosquamis) syn. Istiorhombus WHITLEY 1931 (type-species: Pseudorhombus spinosus) Diagnosis: Moderately thin to quite massive, small otoliths with compressed oval to rectangular shape; ventral rim shallow, more or less horizontal with pronounced but broadly rounded postventral angle, dorsal rim with pronounced pre- and postdorsal angles, the former often developed to a broad projection, posterior tip blunt, rounded or vertically cut, anterior rim without Schwarzhans: Pleuronectiformes 125 rostrum (very feeble rostrum in subgenus Rhombiscus); index l:h 1.15 to 1.65. Otolith size probably not much exceeding 5 to 6 mm. Ostium about two times as long as cauda, widest at about its midpoint (posterior portion of ostium – “fusiform sulcus”). Colliculi usually well separated. Ostial opening reduced, pseudoostial to medial. Cauda ovally shaped, terminating at considerable distance from the posterior rim of the otolith. Dorsal and ventral depressions usually well developed and continuously connected around caudal tip to form a circumsulcal depression. Inner face slightly convex to nearly flat; outer face flat to distinctly convex, smooth to slightly ornamented. Rims sharp, sometimes massive, smooth or very slightly ornamented. Measurements: l:h subgenus Rhombiscus cinnamoneus 1.55-1.65 levisquamis 1.70 h:t ol:cl oh:ch 2.5 3.0 2.4 1.8 1.1 1.25 subgenus Pseudorhombus malayanus 1.70 2.1 javanicus A 1.35-1.45 2.9 javanicus B 1.35-1.45 2.1 arsius 1.35 3.2 neglectus 1.40-1.60 3.2 dupliciocellatus 1.35 nm oligodon 1.25 3.3 annulatus 1.50 nm jenynsii 1.55-1.60 2.8 elevatus 1.40 3.0 pentophthalmus 1.35-1.40 2.7 tenuirastrum 1.45 nm triocellatus 1.40-1.50 2.4 argus 1.15 2.9 †weinfurteri 1.30 3.7-3.9 s.i.a. con.i 0° 0° 7.0 5.4 2.2 1.1 5° 8.0 1.6-1.7 1.1-1.2 10° 3.8 1.8 1.1-1.2 5-10° 6.5 1.8-2.0 1.1-1.2 5-10° 4.0 1.7-1.8 1.1-1.2 10° 2.5 1.5 1.2 5° nm 2.2 1.25 5° 5.7 1.6 1.35 >5° nm 1.7-1.8 1.05-1.2 5° 6.0 2.1 1.5 10° 4.2 2.0-2.4 1.2 15° 5.0 2.3 1.1 5° nm 1.7-2.4 1.1-1.4 5° 2.8 1.45 1.15 10° 3.6 1.9-2.2 1.1-1.25 10° 4.0 Side dimorphism: Side dimorphism is poorly developed in this genus and may not occur in all species. Characters affected concern details of the outline of the otoliths and separation of the colliculi. Ontogeny and variability: The material available to me does not allow detailed conclusions as to ontogenetic changes. However, there are some specimens close to the critical size of 2 to 2.5 mm. Expectedly, they exhibit a more generalized and less characteristic otolith morphology. Also it seems that larger otoliths in several species would become more thickset. Variability seems to be at relatively low level within this genus, concerning mainly details in the outline and the proportions of otolith and sulcus. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: For outgroup relationship of Pseudorhombus see entry to the Pseudorhombus Group (including correlation with the related genus Paralichthys). The second genus of this group – Tarphops – is readily recognized by its extremely compressed nearly circular outline and the completely fused colliculi. Within the genus Pseudorhombus two species groups can readily be distinguished by means of otoliths: a large group containing most of the species which represent the typical picture as described in the generic diagnosis and a small group consisting of P. cinnamoneus and P. levisquamis. Their otoliths show some kind of “relict” rostrum and a much shallower predorsal portion. In this respect they are morphologically intermediate between Paralichthys and Pseudorhombus, although in fact the complete picture is much more in line with Pseudorhombus. This little group could possibly represent the most plesiomorphic character status in Pseudorhombus, which would then also support the assumed relationship with Paralichthys. I have attributed to the two species an available genus name Rhombiscus in subgeneric ranking. Species and distribution: NORMAN (1934) has listed 21 species in this genus plus 3 doubtful species. Assuming P. ctenosquamis as a possible synonym of P. cinnamoneus as discussed by him this would leave the following list of 20 valid species (plus 1 species described later; list may not be complete): P. annulatus, P. argus, P. arsius, P. cinnamoneus, P. diplospilus, P. dupliciocellatus, P. elevatus, P. javanicus, P. jenynsii, P. levisquamis, P. malayanus, P. micrognathus, P. natalensis, P. neglectus, P. oculocirris, P. oligodon, P. pentophthalmus, P. quinquocellatus, P. spinosus, P. tenuirastrum, P. triocellatus. The 21 species of Pseudorhombus are widely distributed through the Indo-West-Pacific. The genus is missing from the Pacific shores of America (see discussion to Paralichthys isocles and reference to GINSBURG, 1952) and the Atlantic. There is, however, one fossil species from the Miocene of Austria (Paratethys) – P. weinfurteri – described as new in the following. A record of P. pentophthalmus from the Pliocene of Japan by OHE (1981, 1983) probably represents a Soleidae, but another record of his described as Solea cf. solea may in fact represent a species of Pseudorhombus. 126 209 210c 210a 211 210b Figs. 209-211: Pseudorhombus (Rhombiscus) cinnamoneus (TEMMINCK & SCHLEGEL 1846) – 10 × Pseudorhombus (Rhombiscus) cinnamoneus (TEMMINCK & SCHLEGEL 1846) Figs. 209-211 syn. Pseudorhombus misakius JORDAN & STARKS 1906 syn. Pseudorhombus formosanus OSHIMA 1927 syn. Spinirhombus taiwanus OSHIMA 1927 ?syn. Spinirhombus ctenosquamis OSHIMA 1927 b Investigated otoliths: 3 otoliths (1 left and 2 right side) from the Inland Sea of Japan, figs. 209-210 ZMH Ot. 12.5.1994.1-2 (leg. BMNH 1905.6.6.2345), fig. 211 BMNH 1905.6.6.234-5. Ontogeny: The smaller specimen (fig. 211) differs from the larger ones in exhibiting a shorter rostrum and a somewhat more crenulated outline. a c Fig. 212: Pseudorhombus (Rhombiscus) levisquamis (OSHIMA 1927) – 10 × Schwarzhans: Pleuronectiformes 127 a c b Fig. 213: Pseudorhombus (Pseudorhombus) malayanus BLEEKER 1866 – 10 × Side dimorphism: Separation of colliculi seems to be less well developed in left hand otoliths. Discussion: P. cinnamoneus is readily recognized by its comparatively strong rostrum, which puts this species somewhat apart from all other species of the genus. Closest resemblance may be with P. levisquamis (which is placed in the same subgenus – Rhombiscus). Otoliths of P. levisquamis, however, show a much shorter rostrum and a peculiar spinous posterior tip. Distribution: Coasts of Japan, China and Taiwan. Pseudorhombus (Rhombiscus) levisquamis (OSHIMA 1927) Fig. 212 Investigated otoliths: 1 otolith (right side) from off Taiwan, SMF 24797. Discussion: Probably closely related to P. cinnamoneus (see respective entry). Distribution: Coasts of China and Taiwan. Pseudorhombus (Pseudorhombus) malayanus BLEEKER 1866 Fig. 213 Investigated otoliths: 1 otolith (right side) from South coast of Java, BMNH 1984.11.14.8. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: The otolith of P. malayanus is characterized by its relatively elongate and massive appearance and the rather strongly reduced dorsal field. Distribution: Widely distributed from the coasts of India through the Malay Peninsula to Indonesia and the Philippines. Pseudorhombus (Pseudorhombus) javanicus (BLEEKER 1853) Figs. 214-219 Investigated otoliths: 7 otoliths; morphotype A: 3 otoliths, 2 (right side) from off Singapore (figs. 214, 216) ZMH Ot. 12.5.1994.3-4 (leg. BMNH 1933.7.31.5-9) and 1 (right side) from off Sumatra (fig. 215) BMNH 1984.11.14.6; morphotype B: 4 otoliths (3 right side and 1 left side, figs. 217-219) from off Singapore, 3 ZMH Ot. 12.5.1994.5-7 (leg. BMNH 1933.7.31.5-9), 1 BMNH 1933.7.31.5-9. Variability: All seven otoliths are of similar sizes. Except for the two morphotypes discussed in the following variability seems to be restricted to minor variations in the expression of the ornamentation and details of the outline. Side dimorphism: The only available left handed otolith exhibits a slightly more pronounced rostrum than the right handed ones. Discussion: Otoliths of P. javanicus resemble those of P. arsius in many respects and differenti- 128 215 214a 214c 214b 216 217a 217c 217c 218 219 Figs. 214-219: Pseudorhombus (Pseudorhombus) javanicus (BLEEKER 1853); figs. 214-216 morphotype A, figs. 217-219 morphotype B; 15 × ation of the two may not always be easy. Otoliths of both species are characterized by a vivid tu- berculous ornamentation of the inner face both on the dorsal and the ventral fields. Schwarzhans: Pleuronectiformes 129 221 220a 220b 220c Figs. 220-221: Pseudorhombus (Pseudorhombus) arsius (HAMILTON 1822) – 10 × It so seems that amongst investigated otoliths of P. javanicus two morphotypes are to be found which can be distinguished from each other quite reliably. Morphotype A is more thin than morphotype B and exhibits more strongly developed predorsal and postventral projections. In this respect morphotype A very strongly resembles otoliths of P. arsius. In fact, it could be that the fishes from which these otoliths were extracted have been mistaken as P. javanicus and rather represent P. arsius. Discussion: Otoliths of P. arsius closely resemble those of the related species P. javanicus (morphotype A, see respective entry). It seems possible that the two species may have been confused to some degree in the past. Distribution: East coast of India through the Malay Peninsula and Indonesia to southern China. Pseudorhombus (Pseudorhombus) neglectus BLEEKER 1866 Figs. 222-223 Pseudorhombus (Pseudorhombus) arsius (HAMILTON 1822) Figs. 220-221 Investigated otoliths: 3 otoliths (right side) from Singapore, ZMH Ot. 2.1.1995.10-11 (leg. BMNH 1933.7.31.13-15) and BMNH 1933.7.31.13-15. ?syn. Pleuronectes maculosus CUVIER 1829 syn. Platessa russellii GRAY 1834 syn. Rhombus lentiginosus RICHARDSON 1843 syn. Platessa balteata RICHARDSON 1843 syn. Rhombus polyspilus BLEEKER 1853 syn. Teratorhombus excisiceps MACLEAY 1882 syn. Pleuronectes mortoniensis DE VIS 1883 syn. Pseudorhombus andersoni GILCHRIST 1905 Discussion: Similar to P. arsius and P. javanicus but more elongate. Investigated otoliths: 5 otoliths (4 right side and 1 left side) from off Singapore, ZMH Ot. 12.5. 1994.8-12 (leg. ZMH 19977). Ontogeny and variability: Both ontogenetic changes and intraspecific variability seem to be at moderate level within this species, mostly concerning details of the outline, as evidenced by investigated specimens and a series of otoliths figured by CHAINE (1936). Side dimorphism: Not apparent. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: P. arsius is the most common and most widely distributed species of the genus. It is known from the East coast of Africa, the Indian Ocean to Indonesia and the Pacific. Distribution: Indo-Australian Archipelago, Philippines and southern China Sea. Pseudorhombus (Pseudorhombus) dupliciocellatus REGAN 1905 Fig. 224 syn. Platophrys palad EVERMANN & SEALE 1907 syn. Pseudorhombus cartwrighti OGILBY 1912 Investigated otoliths: 1 somewhat eroded otolith (right side) from the Java Sea, 05°20’S/ 114°34’E, BMNH 1925.4.2.1-2. Discussion: The single available otolith of this species is somewhat eroded on the inner face. It strongly resembles P. arsius and P. javanicus except for the somewhat more pronounced rostrum. 130 222c 222a 222b 223 Figs. 222-223: Pseudorhombus (Pseudorhombus) neglectus BLEEKER 1866 – 10 × Distribution: Indian Ocean from Nicobar Isl. to Indonesia and NE Australia. Pseudorhombus (Pseudorhombus) oligodon (BLEEKER 1854) Fig. 226 Investigated otoliths: 1 otolith (right side) from off Hongkong, BMNH 79.5.14.74. Discussion: P. oligodon resembles P. arsius and P. javanicus differing merely in being more compressed. NORMAN (1934) related it to P. malayanus. This relationship, however, is not supported by otoliths. Distribution: Coasts of Japan, China and Taiwan. Pseudorhombus (Pseudorhombus) annulatus NORMAN 1927 Fig. 225 Investigated otoliths: 2 otoliths (right side) from off Pakistan, one ZMH Ot. 12.5.1994.13 (leg. BMNH 1983.5.10.4-5), the other BMNH 1983. 5.10.4-5. Discussion: Both available otoliths are relatively small in size and may not exhibit all pertinent diagnostic features. Characteristic is the relatively shallow ventral rim and the massive, some- 224 226a 226c 225 226b Fig. 224: Pseudorhombus (Pseudorhombus) dupliciocellatus REGAN 1905 – 10 × Fig. 225: Pseudorhombus (Pseudorhombus) annulatus NORMAN 1927 – 15 × Fig. 226: Pseudorhombus (Pseudorhombus) oligodon BLEEKER 1854 – 15 × Schwarzhans: Pleuronectiformes 131 228 227a 227c 227b 229a 229b 230a 230b Figs. 227-229: Pseudorhombus (Pseudorhombus) jenynsii (BLEEKER 1855) – 10 × Fig. 230: Pseudorhombus (Pseudorhombus) elevatus OGILBY 1912 – 10 × what crenulated and dorsally pronounced posterior tip. NORMAN (1934) related this species to P. triocellatus. Distribution: Gulf of Oman, coasts of Oman and Pakistan. Pseudorhombus (Pseudorhombus) jenynsii (BLEEKER 1855) Fig. 227-229 syn. Pseudorhombus multimaculatus GÜNTHER 1862 syn. Pseudorhombus multiradiatus MACLEAY 1883 syn. Paralichthys novaecambriae OGILBY 1898 ?syn. Pseudorhombus anomalus OGILBY 1912 Investigated otoliths: 4 otoliths (3 right side and 1 left side) from HWAF station 21,39, ZMH Ot. 12.5.1994.14-17 (leg. ZMH 19983). Ontogeny: The two smaller specimens differ from the larger ones in a more pronounced postdorsal angle and smoother rims. Ontogenetic changes in this species seem to be larger than in the others investigated of the genus. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: Separation of colliculi seems to be less well developed in left hand otoliths. Discussion: Otoliths of P. jenynsii are morphologically intermediate to some extent between those of P. levisquamis and more “typical” species such as P. arsius. From the letter it differs in being more elongate and showing a more regular outline. From the former it is easily distinguished by the more massive predorsal projection and the lack of a spinous posterior tip. Distribution: Along the coasts of northern Australia from Western Australia to southern Queensland. Pseudorhombus (Pseudorhombus) elevatus OGILBY 1912 Fig. 230 syn. Pseudorhombus affinis WEBER 1913 Investigated otoliths: 1 otolith (left side) from off Townsville, northern Queensland, Australia, ZMH Ot. 12.5.1994.18. 132 Investigated otoliths: 2 otoliths, (left and right side) from a single specimen, coast of Fokien, China, ZMH Ot. 12.5.1994.19-20 (leg. ZMH 19984). Side dimorphism: Separation of colliculi is almost indistinctive in left hand otoliths. a c Discussion: Otoliths of P. pentophthalmus are characterized by their rather steeply inclined sulcus, the massive predorsal projection and the strongly reduced postdorsal part. Distribution: Coasts of Korea, Japan, China, Taiwan, Java and Indo-China. b Fig. 231: Pseudorhombus (Pseudorhombus) argus WEBER 1913 – 15 × Discussion: The only otolith available is relatively small and may not exhibit all pertinent diagnostic features. It is a compressed otolith with relatively smooth rims and prominent pre- and postdorsal angles. It resembles small otoliths of P. jenynsii except for being more compressed. Distribution: Persian Gulf, coasts of India, Burma and Queensland (Australia). Pseudorhombus (Pseudorhombus) pentophthalmus GÜNTHER 1862 Figs. 232-233 syn. Pseudorhombus ocellifer REGAN 1905 syn. Pseudorhombus annamensis CHABANAUD 1929 syn. Arnoglossus waikyai SCHMIDT 1931 Pseudorhombus (Pseudorhombus) tenuirastrum (WAIT 1899) Fig. 234 Investigated otoliths: 1 otolith (right side) from off New South Wales, Australia, BMNH 1925. 7.22.8-11. Discussion: The only available otolith is somewhat eroded by formalin and rather small, probably not exhibiting all pertinent diagnostic features. It resembles both P. pentophthalmus (except for being more elongate) and P. triocellatus. Distribution: Restricted to the shores of southeastern Australia, from New South Wales to southern Queensland. 234 232a 233 232c 232b Figs. 232-233: Pseudorhombus (Pseudorhombus) pentophthalmus GÜNTHER 1862 – 10 × Fig. 234: Pseudorhombus (Pseudorhombus) tenuirastrum (WAITE 1899) – 10 × Schwarzhans: Pleuronectiformes 133 235 236a 236c 237 236b 239a 238c 239b 238a 238b Figs. 235-237: Pseudorhombus (Pseudorhombus) triocellatus (SCHNEIDER 1801) – 15 × Figs. 238-239: Pseudorhombus (Pseudorhombus) weinfurteri n.sp. – 15 × Pseudorhombus (Pseudorhombus) triocellatus (SCHNEIDER 1801) Figs. 235-237 Pseudorhombus (Pseudorhombus) argus WEBER 1913 Fig. 231 Investigated otoliths: 5 otoliths (4 right side and 1 left side) from the shores off Orissa, India, 4 ZMH Ot. 12.5.1994.21-24 (leg. BMNH 1927.1.6.410) and 1 BMNH 1927.1.6.4-10. Investigated otoliths: 1 otolith (right side) from an undefined location, BMNH 1977.6.15.5. Variability: Details of the outline and proportions are the main variating characters. Side dimorphism: Separation of colliculi is less developed in left handed otoliths. Discussion: The single small otolith available is easily recognized by its very compressed appearance. Distribution: Aru Islands (Indonesia) and Queensland (Australia). Discussion: These compact, rather thickset otoliths with their relatively regular outline are easy to distinguish from most other species of the genus, including P. annulatus which NORMAN (1934) felt is the most closely related one. As far as otoliths are concerned, P. tenuirastrum bears the closest resemblance. syn. Dicologlossa aff. cuneata – RADWANSKA 1992: fig. 160b, pl. 38, fig. 7 (non fig. 160a, pl. 38, fig. 8) Distribution: East coast of India to the Malay Archipelago. Name: In honor of the late Emil Weinfurter and his outstanding work in fossil otoliths of the Piscium Catalogus, Part Otolithi piscium, Vol. 2 Pseudorhombus (Pseudorhombus) weinfurteri n.sp. Figs. 238-239 134 242 240c 240a 241 243 240c Figs. 240-243: Tarphops oligolepis (BLEEKER 1858) – 15 × Austrian Basins. Holotype: Fig. 238, GBW 1995/5. Type locality: Wetzelsdorf near Preding, Graz Basin, Austria. Age: Florianer Tegel, Upper Badenian, Middle Miocene. Paratype: 1 otolith (fig. 239) from Beczyn near Wadowice (Poland), Badenian, Middle Miocene (described as Dicologlossa aff. cuneata by RADWANSKA, 1992). Diagnosis: Moderately compressed, thin and small otoliths with rather regular outline. Predorsal projection massive, ornamented, postdorsal portion somewhat reduced in height. Description: Outline: Otoliths relatively small (2.0 to 2.5 mm), compressed, with rather regular outline. Dorsal rim with prominent and massive predorsal projection, crenulated and somewhat reduced postdorsal portion; ventral rim regularly curved; anterior and posterior tips blunt, rounded. Otolith very thin, fragile. Inner face: Convex, rather smooth. Sulcus anteriorly inclined, rather narrow and shallow. Ostium about 2 times as long as cauda, very slightly widened, with pseudoostial opening. Cauda slightly deeper and with rounded tip terminating at some distance from the posterior rim of the otolith. Separation of colliculi rather indistinct. Dorsal and ventral depressions rather shallow, narrow, somewhat widened posteriorly, indistinctly connected around caudal tip. Other views: Rims sharp and smooth (except for the predorsal portion). Outer face smooth, concave. Side dimorphism: The holotype is a right hand otolith and the paratype a left hand otolith, which is slightly smaller and less well preserved. In the two specimens side dimorphism is not apparent. Discussion: P. weinfurteri is the first otolith based fossil record of the genus and furthermore originates from outside the present distribution range of the genus. Nevertheless, otolith outline and sulcus morphology characterize it as a typical species of Pseudorhombus. Its very thin appearance and the development of the dorsal rim distinguish P. weinfurteri from all recent species known by otoliths. Closest resembling species are P. arsius and P. oligodon. Distribution: Middle Miocene of the Paratethys, Poland and Austria. Tarphops JORDAN & THOMPSON 1914 Type-species: Rhombus oligolepis BLEEKER 1858 Diagnosis: Moderately massive, small, compressed otoliths with almost circular outline; ventral rim deeply and regularly curved, dorsal rim strongly curved with rounded predorsal projection, posterior tip blunt, nearly vertically cut, anterior rim without rostrum, blunt; index l:h about 1.0. Otolith size probably not much exceeding 2 mm. Colliculi fused, distinction of ostium and cauda practically impossible, but ostium may have originally been much longer than cauda. Sulcus very slightly widened in the middle (“fusiform sulcus”). Ostial opening reduced, pseudoostial. Dorsal and ventral depressions well developed and continuously connected around caudal tip to form a circumsulcal depression. Inner face convex; outer face flat to slightly convex, smooth to slightly ornamented. Rims Schwarzhans: Pleuronectiformes 135 moderately sharp, slightly ornamented. Measurements: oligolepis l:h 1.00-1.05 h:t 3.0 ol:cl nm oh:ch nm s.i.a. 5° con.i 2.5 Side dimorphism: Not apparent. Ontogeny and variability: All investigated specimens are of about the same size and exhibit only a very minor degree of variability. Details of the dorsal rim and ornamentation of the rims are practically the only characters affected. Discussion: NORMAN (1934) felt that Tarphops is very close to Pseudorhombus, probably identical. The close relationship of the two genera is clearly supported by the otoliths. However, Tarphops otoliths differ from those of Pseudorhombus in two aspects, the very compressed shape and the fused colliculi. This in my opinion warrants it to be regarded as a separate genus, possibly representing a specialized offshot from near Pseudorhombus. Species and distribution: In NORMAN (1934) Tarphops was regarded as a monospecific genus from Japan and Taiwan. MASUDA et al. (1984) report a second species – T. elegans – from Japan. In addition OHE (1981, 1983) described otoliths from the Pliocene of Japan as Chascanopsetta cf. lugubris and Engyprosopon aff. ui which likely represent a fossil yet undescribed species of Tarphops. Tarphops oligolepis (BLEEKER 1858) Figs. 240-243 Investigated otoliths: 5 otoliths (4 right side and 1 left side) from the Inland Sea of Japan, 4 ZMH Ot. 13.5.1994.1-4 (leg. BMNH 1905.6.6.237-42) and one BMNH 1905.6.6.237-42. Distribution: Coasts of Japan and Taiwan. Cephalopsetta DUTT & RAO 1965 Type-species: Cephalopsetta ventrocellatus DUTT & RAO 1965 Remarks: Cephalopsetta is a monospecific genus. This species has been rarely recorded from the coasts of India and Pakistan (DUTT & RAO, 1965 Piscium Catalogus, Part Otolithi piscium, Vol. 2 and KOTTHAUS 1977). Otoliths have not been available for investigation. According to KOTTHAUS (1977) the genus is possibly related to Pseudorhombus. Species and distribution: The single species C. ventrocellatus has rarely been caught along the coasts of India and Pakistan in relatively deep water (70 to 170 m). 7.6.3 Syacium Group Genera: Two genera – Syacium and Cyclopsetta – both restricted to the shores of tropical America, but one species of Syacium also occurring along the tropical shores of West Africa. There are several fossil records from the Neogene of America and one of the genus Syacium from the Miocene of Europe (Austria, Paratethys). Definition and relationship: Otoliths of the Syacium Group are amongst the most specialized and easiest for recognition amongst Pleuronectiformes. First of all they are characterized by their “fusiform” sulcus pattern (see chapter 6.1) and the fused colliculi. The fusiform sulcus is characterized by a widening of the sulcus just behind its middle with the anterior and posterior portions being much narrower. This character is similarly developed in the Citharichthys Group and incipiently also in parts of the Pseudorhombus Group. All three groups are here regarded as being interrelated in the way that both, the Syacium Group and the Citharichthys Group, represent specialized offshots from the Pseudorhombus Group. In many other aspects including outline of the otolith or orientation of the sulcus otoliths of the Syacium Group vividly resemble those of the Pseudorhombus Group. Certain characters such as the predorsal projection or the development of the posterior tip of the otolith are often more accentuated. Syacium RANZANI 1840 Type-species: Syacium micrurum RANZANI 1840 syn. Hemirhombus BLEEKER 1862 (type-species: Hemirhombus guineensis, syn. S. micrurum) syn. Aramaca JORDAN 1885 (type-species: Hemirhombus paetulus BEAN 1882, syn. S. papillosum) 136 Diagnosis: Moderately thin and quite large otoliths with compressed oval to rectangular shape; ventral rim shallow, more or less horizontal with pronounced, often angular postventral angle, dorsal rim with pronounced predorsal projection and reduced postdorsal part, predorsal projection often bend outward, posterior tip blunt, rounded or pointed, shifted dorsally, anterior rim blunt without rostrum, nearly vertically cut; index l:h 1.3 to 1.45. Otolith size up to 7 mm, but specimens of 2 to 3 mm in length are already enough mature diagnostically for identification. Colliculi fused, distinction of ostium and cauda practically completely masked. Sulcus inclined, “fusiform”, narrow anterior portion making up about half of the sulcus length, narrow posterior portion short, often pointed. Dorsal and ventral depressions usually rather faint, but more or less continuously connected around caudal tip to form a circumsulcal depression. Inner face convex in particular the predorsal projection, rather smooth; outer face flat to distinctly concave, with little ornamentation. Rims sharp, usually smooth ventrally and ornamented dorsally. Measurements: micrurum papillosum ovale gunteri †dominicensis †syacioides l:h 1.40 1.35-1.40 1.30-1.35 1.30 1.15-1.25 1.30 h:t 4.0 4.5 4.0 3.5 3.5 3.0 ol:cl nm nm nm nm nm nm (oh:ch) s.i.a. con.i 2.0 5-10° 5.0 2.5 20° 5.0 1.2-1.3 10-20° 5.0 1.5 15-20° 5.5 2.0-2.5 10-15° 4.5 2.0 5° 4.0 Side dimorphism: Not apparent. Sexual dimorphism: The otoliths of S. ovale exhibit some kind of “incipient” sexual dimorphism. Judging from the specimens available female otoliths differ from male otoliths in showing less strongly ornamented rims and a pronounced postdorsal concavity. This, however, is only true for otoliths of the blind side (right side), whereas those of the eyed (left) side can not be distinguished. In otoliths of the other species such a trend is not apparent. In this respect it is interesting to note that S. ovale is the only species of the genus in which the interorbital width is different in males and females (larger in males). Other sexual dimorphism of the fish is observed in the elongated pectorals of males (in all species of the genus). Ontogeny and variability: Apart from the observed sexual dimorphism in S. ovale any other variability is quite restricted in the species of this genus. Ontogenetic differences likewise are not apparent within the range of otolith sizes investigated (3 to 6.5 mm). Discussion: Outline and general appearance of otoliths of Syacium resemble certain species of the genus Pseudorhombus (Pseudorhombus Group). However, the sulcus organization (“fusiform”) is quite different. As far as sulcus morphology is concerned, otoliths of the genus Cyclopsetta are most similar to Syacium and both genera are in fact regarded here as closely related. Otoliths of Cyclopsetta are more elongate, show a more median pointed posterior tip and the predorsal projection is more strongly bend outward. Species and distribution: 5 recent species, 3 from the tropical Atlantic coasts of America – S. micrurum, S. papillosum and S. gunteri – and 2 from the tropical Pacific coast of America – S. ovale and S. longidorsale. One species – S. micrurum – is known to be crossing the tropical Atlantic and thus is also present at the tropical coasts of West Africa. NORMAN (1934) has assumed that this crossing of the Atlantic is due to a prolonged pelagic larval life. In addition there are two valid fossil records – S. dominicensis from the Upper Miocene of the Dominican Republic and S. syacioides from the Middle Miocene of Austria. Syacium micrurum RANZANI 1840 Fig. 244 syn. Hippoglossus ocellatus POEY 1856 syn. Hemirhombus guineensis BLEEKER 1862 syn. Citharichthys aethalion JORDAN 1887 Investigated otoliths: 5 otoliths, 3 otoliths (2 right side, fig. 244, and 1 left side) from the Atlantide St. 44, 10°22’N/16°22’W, 2 ZMH Ot. 13.5.1994.56 (leg. BMNH 1962.6.18.3-5) and 1 BMNH 1962.6.18.3-5, 2 eroded otoliths (right and left side) from St.Croix, ZMH Ot. 13.5.1994.7-8 (leg. ZMUC). Variability: The variability of this species is confined to details of the outline as shown in a series of specimens figured by CHAINE (1936). Schwarzhans: Pleuronectiformes 137 a c b Fig. 244: Syacium micrurum RANZANI 1840 – 10 × Discussion: S. micrurum is the species with the most regular outline and the least inclined sulcus. Distribution: S. micrurum represents the only transatlantic Pleuronectiform species. It is known from the tropical Atlantic coasts of America from Florida to Rio de Janeiro and along the tropical West African coast. Discussion: S. papillosum closely resembles S. micrurum. However, the outline of the otoliths is less rounded, more angular and almost rectangular. Both species seemingly are closely related. Distribution: Atlantic coast of America from South Carolina to Rio de Janeiro. Syacium ovale (GÜNTHER 1864) Figs. 249-252 Syacium papillosum (LINNAEUS 1758) Figs. 245-248 syn. syn. syn. syn. Pleuronectes aramaca WALBAUM 1792 Rhombus soleaeformis AGASSIZ 1831 Hippoglossus intermedius RANZANI 1840 Hemirhombus paetulus JORDAN & GILBERT 1883 Investigated otoliths: 7 otoliths (5 right side and 2 left side) from the Dry Tortugas, off Florida, 6 ZMH Ot. 13.5.1994.9-14 (leg. BMNH 1933.10. 12.171-180) and 1 BMNH 1933.10.12. 171.180. Ontogeny and variability: Variability in this species is very limited, restricted to details of the outline. Smaller specimens are somewhat more rounded, generalized in outline, in particular as far as the ornamentation of the dorsal rim is concerned. Piscium Catalogus, Part Otolithi piscium, Vol. 2 syn. Citharichthys latifrons JORDAN & GILBERT 1882 (male specimen acc. to NORMAN, 1934) Investigated otoliths: 5 otoliths, 3 from male specimens (2 right side and 1 left side, figs. 249250) from the Pacific coast of Panama, ZMH Ot. 13.5.1994.15-16 (leg. BMNH 1903.5.15.270-71) and BMNH 1903.5.15.270-71, 2 from a female specimen (right and left side, figs. 251-252) from the Pacific coast of Colombia, ZMH Ot. 13.5.1994.1718 (leg. ZMH 19956). Variability: Otoliths of S. ovale a remarkable for some kind of “incipient” sexual dimorphism (see entry to genus). Otherwise variations are very minute. Discussion: Otoliths of S. ovale can be easily recognized by the much less widened postcentral 138 245 246 247a 248 247b 247c Figs. 245-248: Syacium papillosum (LINNAEUS 1758) – 10 × part of the sulcus, which finds its expression in the index oh:ch. In outline of the otolith and other characters they are very similar to S. papillosum. Investigated otoliths: 2 otoliths (left and right) from off Dry Tortugas, Florida, ZMH Ot. 2.1.1995.12 (leg. BMNH 1933.10.12.127-36) and BMNH 1933.10.12.127-36. Distribution: Pacific coast of tropical America from the Gulf of California to Colombia. Discussion: Similar to S. ovale but with smooth, somewhat undulating rims, a more widened central part of the sulcus and a pointed postdorsal tip. Syacium gunteri GINSBURG 1933 Figs. 253-254 Distribution: Coasts of Florida and Louisiana. syn. Syacium longleyi NORMAN 1933 Schwarzhans: Pleuronectiformes 139 249c 250 249a 249b 251a 251b 252 Figs. 249-252: Syacium ovale (GÜNTHER 1864) – 10 × Syacium dominicensis n.sp. Figs. 255-257 syn. Bothidae indet. – NOLF & STRINGER 1992: pl. 17, fig. 15-16 Name: After the Dominican Republic, from where the type-material was obtained. Holotype: Fig. 255, NMB P 140. Type locality: Rio Mao, Cibao Valley, northern Dominican Republic. Age: Cercado Formation, Upper Miocene. Paratypes: 7 otoliths (figs. 256-257), topo- and stratitypic, loc. NMB 15904, 16918, 16923, 16924, 17287 (2 specimens); NMB P 141. Diagnosis: Compressed, moderately thickset otoliths with almost rectangular outline. All rims rather smooth. Sulcus inclined, considerably widened postcentrally. 253a 253c 254 253b Figs. 253-254: Syacium gunteri GINSBURG 1933 – 10 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 140 256 255a 255c 257 255b Figs. 255-257: Syacium dominicensis n.sp. – 15 × Description: Outline: Compressed, medium sized otoliths (up to 4.5 mm) with almost rectangular outline. Pre- and postdorsal portions well developed, angular. Posterior tip shifted dorsally, somewhat pointed. Postventral portion deeply curved. Inner face: Convex in both directions, particularly so along the vertical axis. Colliculi completely fused. Sulcus shallow, moderately narrow, with a distinctly widened portion just behind its middle. Sulcus opening pseudoostial. Dorsal and ventral depressions feeble, narrow, usually connected around the caudal tip. Other views: Rims moderately sharp to sharp, smooth, somewhat undulating. Outer face rather smooth, flat to slightly concave. Discussion: S. dominicensis is considerably more compressed than the known recent species. In outline and sulcus character it resembles best S. papillosum. Side dimorphism: Not apparent. Discussion: Although a typical otolith of the genus Syacium, S. syacioides is readily recognized by a number of characters, such as the more median position of the ventral curvature, the Variability: All the investigated specimens are of similar sizes and do show very little variations. Syacium syacioides (WEINFURTER 1952) Fig. 258 syn. Pleuronectidarum syacioides WEINFURTER 1952 – WEINFURTER 1952: pl. 4, fig. 5 Investigated otoliths: Weinfurter’s holotype (and unique specimen) from the Florianer Tegel, Badenian, Middle Miocene of Wetzelsdorf, Graz Basin, Austria, LMJ. Schwarzhans: Pleuronectiformes 141 course of the dorsal rim, the more thickset appearance and the slightly convex outer face. In many ways it is morphologically intermediate between the genera Syacium and Cyclopsetta. Distribution: S. syacioides so far is the only strictly Old World species of the genus, indicating that Syacium has crossed the Atlantic more than once in the past. It is known only from the single holotype obtained from Middle Miocene strata in southern Austria (Paratethys). Cyclopsetta GILL 1889 Type-species: Hemirhombus fimbriatus GOODE & BEAN 1886 syn. Azevia JORDAN & GOSS 1889 (type-species: Citharichthys panamensis) syn. Dorsopsetta NIELSEN 1963 (type-species: D. norma, syn. C. querna acc. to van der HEIDEN & PEREZ 1993) Diagnosis: Moderately thin and quite large otoliths with an elongate shape; ventral rim with a shallow postventral curvature, dorsal rim with pronounced predorsal projection and shallow postdorsal part, predorsal projection strongly bend outward, posterior tip rounded, somewhat shifted dorsally, anterior rim blunt without rostrum; index l:h 1.4 to 1.8. Otolith size up to 8 mm. Colliculi fused, distinction of ostium and cauda practically completely masked. Sulcus slightly inclined, “fusiform”, narrow anterior portion making up about half of the sulcus length, narrow posterior portion short, with rounded or pointed tip. Dorsal and ventral depressions usually faint except for the postventral portion which is well set off from the sulcus, more or less continuously connected around caudal tip to form a circumsulcal depression. Inner face slightly convex in the horizontal direction but strongly convex in the vertical direction, particular so the predorsal projection, rather smooth; outer face flat to distinctly concave in the vertical direction, with little ornamentation. Rims sharp, usually smooth ventrally, sometimes ornamented dorsally. Piscium Catalogus, Part Otolithi piscium, Vol. 2 a c b Fig. 258: Syacium syacioides (WEINFURTER 1952) – 15 × Measurements: chittendeni querna fimbriata panamensis †transitus l:h 1.40-1.50 1.65 1.60 1.75-1.80 1.30-1.35 h:t 3.5 3.0 4.0 3.5 3.0 ol:cl nm nm nm nm nm (oh:ch) 1.9-2.3 2.1 2.0 1.6-1.9 1.6-2.3 s.i.a. 5-10° 10° 5° 5-10° 5-10° con.i 7 9 5 5 6 Side dimorphism: Side dimorphism is not apparent in two of the three investigated recent species. In the case of C. chittendeni left hand otoliths seem to be slightly more compressed than right hand specimens. Ontogeny and variability: A single, very small otolith (about 1 mm) of C. querna is more rounded and compressed in outline (generalized) and exhibits a very vivid marginal crenulation. Diagnostically valid characters may not have been achieved with otoliths smaller than 3 to 4 mm in size. Variability of adult specimens on the other hand seems to be very limited. Discussion: Cyclopsetta apparently is closely related to Syacium. It exhibits the same type of “fusiform” sulcus morphology with its fused colliculi. Otoliths of Cyclopsetta differ in being more elongate and more rounded, less rectangular in outline. Species and distribution: NORMAN (1934) recorded 4 recent species from the tropical coasts of America – C. chittendeni and C. fimbriata from the Atlantic and C. querna and C. panamensis from the Pacific – plus a doubtful fifth species from the Pacific – C. maculifera. In addition a possible C. aff. panamensis is recorded as a fossil from the Pliocene of the Dominican Republic and C. transitus is being described as a new species from the Lower Miocene of Trinidad. 142 259 260a 260b 260c 261a 261c 261b Figs. 259-260: Cyclopsetta chittendeni BEAN 1895 – 10 × Fig. 261: Cyclopsetta querna (JORDAN & BOLLMAN 1890) – 10 × Cyclopsetta chittendeni BEAN 1895 Figs. 259-260 Variability: Variability in this species is limited to minor modifications of the outline. Investigated otoliths: 8 otoliths, 4 otoliths (3 right side and 1 left side, figs. 259-260) from British Guiana, ZMH Ot. 14.5.1994.1-3 (leg. BMNH 1961.9.4.106) and BMNH 1961.9.4.106, 4 otoliths (2 right side, 2 left side) from Trinidad, ZMH Ot. 14.5.1994.4-7 (coll. Schwarzhans) Side dimorphism: Right hand otoliths seem to be slightly more compressed than left hand otoliths. Discussion: Otoliths of C. chittendeni are more compressed than those of the two other recent species investigated. Schwarzhans: Pleuronectiformes 143 Cyclopsetta fimbriata (GOODE & BEAN 1886) Fig. 262 Investigated otoliths: 1 otolith (right side) from off British Guiana, 07°53’N/57°25’W, BMNH 1961.9.4.105. Discussion: The only available otolith is somewhat eroded marginally, in particularly so its predorsal region, which can not be reconstructed. Otherwise it resembles both C. chittendeni and C. querna, but shows a slight development of a rostrum and a rather pointed posterior tip. a Distribution: Deep water in the Gulf of Mexico. b Fig. 262: Cyclopsetta fimbriata (GOODE & BEAN 1886) – 10 × Distribution: Caribbean, Trinidad to Guiana. Cyclopsetta querna (JORDAN & BOLLMAN 1890) Fig. 261 syn. Dorsopsetta norma NIELSEN 1963 acc. to van der HEIDEN & PEREZ 1993) Investigated otoliths: 6 otoliths, 3 large otoliths (right side, fig. 261) from the Pacific coast of Panama, ZMH Ot. 14.5.1994.8-9 (leg. BMNH 1903.5.15.246-7) and BMNH 1903.5.15.246-7, 3 small otoliths (2 right side, one left side) without location, SMF unreg. Ontogeny: The very small specimens are somewhat more generalized in outline (more rounded and compressed). All their rims are intensely crenulated. Cyclopsetta panamensis (STEINDACHNER 1875) Figs. 263-265 Investigated otoliths: 4 otoliths (2 right and 2 left side, figs. 263-264) from off Mazatlan, Pacific coast of Mexico, ZMH Ot. 14.5.1994.10-11 (leg. BMNH 95.5.27.219-20) and BMNH 95.5.27.219-20. – 1 fossil otolith (as C. aff. panamensis, fig. 265) from the Pliocene of Arroyo Zalaya, Dominican Republic (described by NOLF & STRINGER 1992 as ?Pleuronectidae indet., pl. 17, fig. 20; NMB P 145). Variability: Not apparent from the material available. Discussion: C. panamensis is the most elongate and most delicately ornamented otolith to be found in this genus. Distribution: Pacific coast of America from Lower California to Panama. In addition, there is a possible fossil record from the Atlantic Pliocene of the Dominican Republic (as C. aff. panamensis). Discussion: C. querna is quite similar to C. chittendeni from the Atlantic side of America. It differs in being slightly more elongate and exhibiting a more flat inner face. Cyclopsetta transitus n.sp. Figs. 266-267 Distribution: Pacific coast of Panama and Columbia. syn. genus Pleuronectiformorum sp.1 – NOLF 1976: pl. 9. fig. 14 Piscium Catalogus, Part Otolithi piscium, Vol. 2 144 264 263a 263b 263c Figs. 263-264: Cyclopsetta panamensis (STEINDACHNER 1875) – 10 × Name: transitus (lat.) = transitional, referring to the intermediate morphology between the two related genera Cyclopsetta and Syacium. Holotype: Fig. 266, NMB SA 1530. Type locality: Tamanaquito river banks, Trinidad, (K.R.6666). Age: Brasso Formation, Lower Miocene. Paratypes: 2 otoliths (fig. 267), Mayo river banks, Trinidad (K.R.25953), Nariva Formation, Lower Miocene, NMB SA. Diagnosis: Compressed, moderately thickset otoliths with a very prominent predorsal projection, which is not very strongly bend outward. Sulcus comparatively short. Ventral rim massive, posterior rim blunt. Description: Outline: Compressed, rather small otoliths with a prominent predorsal projection, which is not very strongly bend outward. Dorsal rim otherwise shallow, smooth. Ventral rim deeply curved, smooth. Posterior tip blunt, sometimes faintly crenulated. Anterior tip blunt. Inner face: Moderately convex and rather smooth. Sulcus rather short, slightly inclined, with completely fused colliculi and the typical “fusiform” shape. Sulcus opening reduced pseudoostial. Dorsal and ventral depressions rather shallow, but wide and connected around the caudal tip. Other views: Rims moderately sharp and rather smooth. Outer face smooth, flat to slightly convex. Side dimorphism: Not apparent. Ontogeny and variability: The smallest specimen has been selected as holotype, since the two larger ones are slightly eroded. It differs slightly in the somewhat crenulated posterior rim and a b Fig. 265: Cyclopsetta aff. panamensis (STEINDACHNER 1875) – 15 × Schwarzhans: Pleuronectiformes 145 267a 267b 266 267c Figs. 266-267: Cyclopsetta transitus n.sp. – 15 × the narrower sulcus. The latter, however, may not be regarded as a ontogenetic feature but due to a certain variability. Discussion: C. transitus is readily distinguished from the recent species of the genus by its more compressed and more thickset appearance. In this respect it is somewhat intermediate morphologically to the species of the related genus Syacium, hence the etymology. However, outline and lesser inclination of the sulcus characterize this species as a representative of Cyclopsetta. 7.6.4 Citharichthys Group Genera: Three genera – Citharichthys, Orthopsetta and Etropus – distributed along the shores of both Americas. A single species of the genus Citharichthys is known from the tropic coasts of West Africa. In addition, there is one fossil record of the genus Etropus from the Miocene of the Dominican Republic and possibly a second one from the Miocene of Ecuador (A. Müller, com. pers.). – In NORMAN (1934) and JORDAN, EVERMANN & CLARK (1930) Orthopsetta was treated as a subgenus of Citharichthys. In this treatise it is ranked a genus, primarily based on otolith morphology. Definition and relationship: Otoliths of the Citharichthys Group are easily recognized by the following characters: colliculi completely fused; sulcus opening reduced to a medial position; sulcus shape “fusiform” (see chapter 6.1., sulcus widened just behind its middle with the anterior and posterior portions being narrower); otoliths compressed with a typical pentagonal outline, the Piscium Catalogus, Part Otolithi piscium, Vol. 2 corners being the predorsal, postdorsal and midventral angles as well as the anterior and posterior tips, the latter usually being somewhat projecting. The “fusiform” sulcus morphology and the fused colliculi closely resemble otoliths of the Syacium Group and is also found incipiently in certain members of the Pseudorhombus Group. In fact, both the Citharichthys and Syacium Groups are thought to have derived from a common ancestor from within or close to the Pseudorhombus Group. Within the Citharichthys Group the genus Citharichthys probably represents the most plesiomorphic morphology. The two other genera – Orthopsetta and Etropus – exhibit a tendency to reduce the sulcus morphology resulting in a more regularly ovally shaped sulcus and variations of the outline of the otolith. Citharichthys BLEEKER 1862 Type-species: Citharichthys cayennensis BLEEKER 1862 (syn. C. spilopterus) Diagnosis: Relatively thin, small otoliths with a compressed pentagonal shape; ventral rim deeply curved, with a rounded medioventral angle; dorsal rim with pronounced predorsal projection and angular postdorsal angle, predorsal projection not or only slightly bend outward, portion between postdorsal angle and posterior tip slightly concave; posterior tip pointed, somewhat projecting, occupying a median position; anterior rim with obtuse median angle, but without rostrum; index l:h 1.2 to 1.35. Otolith size possibly not exceeding much 3 mm. 146 269a 268 270 269b 271c 271a 272 271b Figs. 268-269: Citharichthys spilopetrus GÜNTHER 1862 – 15 × Figs. 270-272: Citharichthys stampflii STEINDACHNER 1894 – 15 × Colliculi fused, distinction of ostium and cauda practically completely masked. Sulcus more or less horizontal, “fusiform”, narrow anterior portion making up about one third of the sulcus length, narrow posterior portion short, somewhat shifted towards dorsal. Dorsal and ventral depressions moderately deep, more or less continuously connected around caudal tip to form a circumsulcal depression. Inner face moderately convex, rather smooth; outer face flat to slightly concave, with little ornamentation. Rims sharp, usually smooth, sometimes slightly undulated or crenulated. Measurements: spilopterus stampflii gilberti macrops l:h 1.20-1.25 1.30-1.35 1.40 1.20 h:t 4.5 4.5 4.7 4.5 ol:cl nm nm nm nm (oh:ch) 1.4 1.3 1.5 1.4-1.6 con.i 5 4.5 6 3.5 Side dimorphism: Not apparent. Ontogeny and variability: Otoliths of relatively small sizes in the order of 2 mm already exhibit all pertinent diagnostic features. Range of variations is moderate, restricted to details of the outlines of the otolith and the sulcus. Discussion: NORMAN (1934) differentiated Citharichthys and Orthopsetta (as subgenera) primarily on the basis of the shape of the head – closely compressed in Citharichthys, more elongated in Orthopsetta. Based on otoliths, the distinction is even easier and this has led me to regard Orthopsetta as a separate genus. Otoliths of Citharichthys are more angular, pentagonal in outline, the sulcus is narrower, with the typical “fusiform” outline, whereas in Orthopsetta it tends to become regularly ovally in shape. Also Citharichthys otoliths are thinner, with a distinctly convex inner face, whereas in Orthopsetta the inner face is practically flat. It so seems that Orthopsetta represents the more advanced (in this case “reduced”) otolith morphology and Citharichthys the more plesiomorphic one. However, since otoliths are not known from all the species in these two genera, morphologically intermediate forms may have to be expected. The differentiation of the two genera Citharichthys and Orthopsetta as suggested by their otolith morphology does not completely fit with NORMAN’s subdivision (in two subgenera). Based on otoliths I would like to include more species in Orthopsetta than NORMAN did. From his morphological analyses of the fishes it seems that the Schwarzhans: Pleuronectiformes 147 b a Fig. 273: Citharichthys gilberti JENKINS & EVERMANN 1889 – 15 × shape of the head may not be the most useful character to distinguish the two genera. Instead, there are three other characters which seem to correlate quite well with the two otolith groups proposed. They are: shape of the gill rakers (moderate to stout in Citharichthys, long and slender in Orthopsetta), scales (ctenoid on eyed side and cycloid on blind side in Citharichthys, cycloid on both sides in Orthopsetta) and number of rays in the anal fin (less than 65 in Citharichthys, more than 67 in Orthopsetta). species investigated and exhibit rather sharp angles along the outline. Also the sulcus is relatively short. Species and distribution: Tentatively, I have placed 8 species in the genus Citharichthys based on ichthyological grounds as discussed above. They are: C. abbotti, C. arenaceus, C. macrops, C. spilopterus and C. uhleri from the Atlantic coasts of America, C. gilberti and C. platophrys from the Pacific coasts of America and C. stampflii from West Africa. Otoliths are only known from four of these species – C. gilberti, C. macrops, C. spilopterus and C. stampflii. Investigated otoliths: 5 otoliths (3 right side, figs. 270-271; 2 left side, fig. 272) from of Togo, West Africa, ZMH Ot. 14.5.1994.16-20 (leg. ZMH 1884 and ZMH 19944). Citharichthys spilopterus GÜNTHER 1862 Figs. 268-269 syn. Citharichthys cayennensis BLEEKER 1862 syn. Citharichthys guatimalensis BLEEKER 1863 syn. Hemirhombus fuscus POEY 1868 Investigated otoliths: 4 otoliths, 2 otoliths (right side and left side, fig. 268) from Santiago de Cuba, ZMH Ot. 14.5.1994.12-13 (leg. ZMH 19882) and 2 otoliths (right side, fig. 269) from the Bahamas, ZMH Ot. 14.5.1994.14-15 (leg. ZMH 19947). Discussion: Otoliths of C. spilopterus are more compressed than those of the two other recent Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Atlantic coast of America from New Jersey to Brazil. Citharichthys stampflii STEINDACHNER 1894 Figs. 270-272 Discussion: C. stampflii apparently is closely related to C. spilopterus. Their otoliths are slightly more elongate and show a somewhat longer sulcus. Distribution: West African coast from Senegal to Angola. Citharichthys gilberti JENKINS & EVERMANN 1889 Fig. 273 syn. Citharichthys sumichrasti JORDAN & GOSS 1889 Investigated otoliths: 1 otolith (right side) from off Ecuador, Guyas river, BMNH 1938.11.18.49. Discussion: Similar to C. spilopterus and C. stampflii but with less accentuated dorsal angles and slightly more elongate. In sulcus morphology C. gilberti is somewhat intermediate between Citharichthys and Orthopsetta. 148 274c 275 274a 274b Figs. 274-275: Citharichthys macrops DRESEL 1885 – 15 × Distribution: Pacific coast of America from Lower California to Peru. Citharichthys macrops DRESEL 1885 Figs. 274-275 Investigated otoliths: 2 otoliths (left and right side) from off Georgia, USA, ZMH Ot. 14.5.1994. 21-22 (leg. SMF 13008). Discussion: Otoliths of C. macrops are characterized by their delicately crenulated rims and the more rounded posterior tip. Distribution: South Atlantic and Gulf Coasts of the United States northward to N. Carolina. Orthopsetta GILL 1862 Type-species: Psettichthys sordidus GIRARD 1856 syn. Metoponops GILL 1864 (type-species: Metoponops cooperi, syn. O. sordidus) Diagnosis: Moderately thickset, small otoliths with a compressed, rounded pentagonal shape; ventral rim deeply and rather regularly curved, with a rounded medioventral angle, dorsal rim with pronounced predorsal projection and rounded postdorsal angle, predorsal projection not bend outward, portion between postdorsal angle and posterior tip slightly concave, posterior tip rounded, somewhat projecting, occupying a median to submedian position, anterior rim bluntly rounded; index l:h 0.9 to 1.15. Otolith size possibly not exceeding much 4.5 mm. Colliculi fused, distinction of ostium and cauda practically completely masked. Sulcus more or less horizontal, indistinctly “fusiform” to oval in shape. Dorsal and ventral depressions moderately deep, more or less continuously connected around caudal tip to form a circumsulcal depression. Inner face flat to very slightly convex, rather smooth; outer face convex, smooth or with little ornamentation. Rims moderately sharp, usually smooth, sometimes slightly undulated or crenulated. Measurements: stigmaeus sordidus fragilis xanthostigma arctifrons cornutus l:h 1.00-1.15 0.95-1.10 1.00 0.95-1.00 0.90-1.00 0.90-0.95 h:t 3.7 5.5 3.8 4.2 4.0 2.9 ol:cl nm nm nm nm nm nm (oh:ch) 1.2-1.4 nm nm nm nm 1.5-1.7 con.o 3.7 3.5 3.5 2.8 2.9 2.5 Side dimorphism: Not apparent. Ontogeny and variability: Smaller otoliths are usually not as extremely compressed than larger ones. Diagnostic size may be reached with 2 to 2.5 mm. Intraspecific variability somewhat variably, but usually of moderate nature. Details and proportions of otolith outline are the most strongly affected parameters, but in some instances outline of sulcus may be affected as well. Discussion: Otoliths of Orthopsetta may be distinguished from those of the related genus Citharichthys by their more strongly reduced sulcus morphology, the more roundish shape of the otoliths which are also more compressed and the almost completely flat inner face (resulting in a Schwarzhans: Pleuronectiformes 149 276 278a 277 278b 278c Figs. 276-278: Orthopsetta stigmaeus (JORDAN & GILBERT 1883) – 15 × convex outer face). For further discussion including ichthyological differentiation of the two genera see entry to Citharichthys. Distinction from Etropus in many aspects is less clear. NORMAN (1934) noted to Etropus: “very close to Citharichthys, but eyes always separated by a narrow, bony ridge”. Otoliths do show a certain tendency to widen the sulcus. They are not always as compressed as those of Orthopsetta and also even more roundish in shape. Often, not only the postdorsal but also the postventral rims are mildly concave. However, all these otolith characters are so subtle and so variable in nature that in my opinion otoliths of the two genera Orthopsetta and Etropus will not always be distinguishable on the generic level. Species and distribution: Following the ichthyological parameters proposed for differentiation of the two genera Citharichthys and Orthopsetta as discussed in the entry to Citharichthys, I have tentatively placed the following species in the genus Orthopsetta: O, amblybregmatus, O. arctifrons, O. cornutus, O. dinoceros and O. gymnorhinus from the Atlantic coasts of America and O. fragilis, O. mariajorsiae, O. sordidus, O. stigmaeus and O. xanthostigma from the Pacific coasts of America. Except for O. dinoceros, O. gymnorhinus, O. mariajorsiae and O. amblybregmatus otoliths are known from all of these species. Orthopsetta stigmaeus (JORDAN & GILBERT 1883) Figs. 276-278 Investigated otoliths: 5 otoliths (4 right side, figs. 277-278; 1 left side, fig. 276) from off California, ZMH Ot. 14.5.1994.23-27 (leg. Fitch). Variability: Variability within this species is relatively small, restricted to details of the outline. Discussion: O. stigmaeus in many aspects exhibits the most plesiomorphic otolith morphology in this genus. The outline of the otoliths is rounded pentagonal, the sulcus still rather long with an indistinct “fusiform” shape and the inner face is slightly convex. Also it is more elongate than most other species of the genus. Distribution: Pacific coast of North America from Oregon to southern California. Orthopsetta sordidus (GIRARD 1856) Figs. 279-282 syn. Metoponops cooperi GILL 1864 Investigated otoliths: 7 otoliths (4 right side, figs. 279, 280, 282; 3 left side, fig. 281) from off California, ZMH Ot. 14.5.1994.28-34 (leg. Fitch) Ontogeny and variability: Otoliths of O. sordidus show a rather strong degree of allometric ontogenetic changes. Otoliths of up to 3.5 mm in size are Piscium Catalogus, Part Otolithi piscium, Vol. 2 150 280a 279 280b 280c 281 282 283a 283c 283b Figs. 279-282: Orthopsetta sordidus (GIRARD 1856) – 15 × Fig. 283: Orthopsetta fragilis (GILBERT 1891) – 15 × Schwarzhans: Pleuronectiformes 151 285 284a 284c 284b Figs. 284-285: Orthopsetta ×anthostigma (GILBERT 1890) – 15 × considerably less compressed than the large ones of 4 to 4.5 mm length. Variations of the outline of the otolith is moderate and mainly concerns the expression of the dorsal and the posterior rims. Discussion: O. sordidus differs from O. stigmaeus in the more compressed and more rounded outline and the rather wide and ovally shaped sulcus. Even more closely related is O. fragilis, which mainly differs in the more massive dorsal field and the somewhat more thickset appearance. However, once a larger series of otoliths of O. fragilis becomes available, the limits between the otoliths of both species may very well fade away. Distribution: Pacific coast of North America from British Columbia to Lower California. Orthopsetta fragilis (GILBERT 1891) Fig. 283 Investigated otoliths: 1 otolith (right side) from the Gulf of California, BMNH 1900.9.29.252. Discussion: Very close to O. sordidus (see respective entry). Distribution: Pacific coast of North America, restricted to the Gulf of California. Orthopsetta xanthostigma (GILBERT 1890) Figs. 284-285 Investigated otoliths: 5 otoliths (3 right side, fig. 284; 2 left side, fig. 285) from off California, ZMH Ot. 14.5.1994.35-39 (leg. Fitch). Variability: As in most species of this genus the outline of the otolith is the character most strongly affected by variability. However, in the case of O. xanthostigma the degree of variations is relatively small. Discussion: Otoliths of O. xanthostigma are quite compressed and exhibit a rather regularly rounded dorsal rim. The sulcus is wide, oval in shape and rather short. The short sulcus and the shape of the otolith distinguishes it from O. sordidus and O. fragilis. Distribution: Pacific coasts of North America, both coasts of Lower California. Orthopsetta arctifrons (GOODE 1881) Figs. 286-289 Investigated otoliths: 5 otoliths (3 right side, figs. 287, 289; 2 left side, figs. 286, 288) from off Virginia, USA, ZMH Ot. 14.5.1994.40-44 (leg. ISH). Variability: Details of the outline can be quite variable in this species. This concerns presence Piscium Catalogus, Part Otolithi piscium, Vol. 2 152 286 287a 287c 287b 288 289 Figs. 286-289: Orthopsetta arctifrons (GOODE 1881) – 15 × or absence of a slight marginal crenulation as well as degree of “roundness” of the outline. In general, however, otoliths are more regularly rounded than those of any other species in the genus. Discussion: Seemingly, O. arctifrons somewhat stands apart from the rest of the species in this genus. Their otoliths are easily recognized by their almost round outline and the extremely short sulcus. Distribution: Atlantic coasts of North America, in relatively deep waters (70 to 350 m) of the Gulf Stream. Orthopsetta cornutus (GÜNTHER 1880) Figs. 290-291 syn. Citharichthys unicornis GOODE 1881 Investigated otoliths: 4 otoliths (2 right side, fig. 290; 2 left side, fig. 291) West of Trinidad (10°51’N/60°29’W), ZMH Ot. 14.5.1994.45-46 (leg. ZMUC 853448-49) and ZMUC 853448-49. Variability: Otoliths of this species seem to be quite variable as far as their outline is concerned. Discussion: O. cornutus probably shows the most compressed and most thickset otoliths in this genus. In fact, it is the only species in which the ventral rim is more deeply curved than the dorsal rim. The sulcus is small and short. These characters make O. cornutus quite unmistakable. Distribution: Atlantic coast of Central America and Brazil, in relatively deep waters (60 to 600 m) of the Gulf Stream. Etropus JORDAN & GILBERT 1882 Type-species: Etropus crossotus JORDAN & GILBERT 1882 Diagnosis: Moderately thickset, small otoliths with a compressed, rounded pentagonal shape; ventral rim moderately curved, broadly rounded or with a rounded medioventral angle, postventral portion often concave, dorsal rim with rather shallow predorsal projection and rounded postdorsal angle, predorsal projection not bend outward, postdorsal portion straight or slightly concave, posterior tip pointed or rounded, projecting, occupying a median position, anterior rim blunt or rounded; index l:h 1.2 to 1.3. Otolith size possibly not exceeding much 3.5 mm. Schwarzhans: Pleuronectiformes 153 290a 290c 291 290b Figs. 290-291: Orthopsetta cornutus (GÜNTHER 1880) – 15 × Colliculi fused, distinction of ostium and cauda practically completely masked. Sulcus more or less horizontal, oval in shape, not reduced in length. Dorsal and ventral depressions moderately deep, more or less continuously connected around caudal tip to form a circumsulcal depression. Inner face moderately convex to almost flat, rather smooth; outer face flat to moderately convex, usually smooth. Rims moderately sharp, usually smooth, sometimes slightly undulated. Measurements: crossotus intermedius longimanus microstomus †concaviventris l:h 1.25-1.30 1.20 1.10-1.25 1.15-1.20 1.05-1.15 h:t 4.5 4.0 3.4 3.5 3.3 ol:cl nm nm nm nm nm (oh:ch) nm nm nm nm nm con.i 4.5 4.5 6.5 7.0 3.0 Side dimorphism: Not apparent. Ontogeny and variability: Ontogenetic changes do not seem to play a major role in the species of this genus. Even small specimens of 1.5 to 2 mm in size exhibit all pertinent diagnostic characters. Variability on the other hand can be quite considerable, as exemplified by the figures to E. longimanus and concerns many aspects of the outline of the otolith. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: As stated before otoliths of Etropus are hardly distinguishable from those of the related genus Orthopsetta (see entry to this genus for lengthy discussion). One useful character adherent to many but not all species is the slightly concave postventral rim. Likewise, NORMAN (1934) stated that Etropus is very similar to Citharichthys (including Orthopsetta as a subgenus in his views), but eyes are always separated by a narrow, bony ridge. Species and distribution: There are 9 nominal recent species recorded, 7 from the Atlantic coasts of America – E. crossotus, E. cyclosquamus, E. delsmani, E. intermedius, E. longimanus, E. microstomus and E. rimosus – and 4 from the Pacific coast of America – E. crossotus, E. delsmani, E. peruvianus and E. ectenes. Thus E. crossotus and E. delsmani are among of the very few species occurring simultaneously on both sides of America. Otoliths are only known from 4 species, namely E. crossotus, E. intermedius, E. longimanus and E. microstomus. However, most of the remaining species seem to be extremely rare, some of them based on one or two specimens only. In addition, there is a fossil record from the Upper Miocene of the Dominican Republic, described here as E. concaviventris and possibly a second record from the Miocene of Ecuador (com. pers. A. Müller). 154 292a 293 292c 294 292b 295b 295a Figs. 292-294: Etropus crossotus JORDAN & GILBERT 1882 – 15 × Fig. 295: Etropus intermedius NORMAN 1933 – 15 × Etropus crossotus JORDAN & GILBERT 1882 Figs. 292-294 sides of America. In the Atlantic it is found from Chesapeake Bay to the West Indies and in the Pacific from Lower California to Panama. syn. Citharichthys crossotus atlanticus PARR 1931 Investigated otoliths: 3 otoliths (right side) from off Mazatlan, Pacific coast of Mexico, ZMH Ot. 14.5.1994.47-48 (leg. BMNH 95.5.27.225-29) and BMNH 95.5.27.225-29. Variability: Variations in this species seems to be limited to the expression of the predorsal projection. Discussion: Otoliths of E. crossotus are very similar to those of the various species of the genus Citharichthys. Similar are the thin appearance, the rather elongate and pentagonal outline of the otolith and the long and narrow sulcus. Differences are so delicate that from otoliths alone one would certainly be tempted to place this species in the genus Citharichthys altogether. Etropus intermedius NORMAN 1933 Fig. 295 Investigated otoliths: 1 otolith (right side) from off Georgetown, British Guiana, BMNH 1950.5. 15.46. Discussion: Very similar to both E. crossotus and E. longimanus. Main difference is the strongly developed predorsal projection resulting in a very blunt anterior rim. Whether this character is sufficient to distinguish otoliths of this species from those of the two others mentioned before remains to be verified once more material has become available. Distribution: Atlantic coast of South America from Trinidad to Rio de Janeiro. Distribution: E. crossotus is the only Pleuronectiform species occurring simultaneously on both Schwarzhans: Pleuronectiformes 155 296c 296a 297 296b 298 299 300c 300b 301 300a Figs. 296-299: Etropus longimanus NORMAN 1933 – 15 × Figs. 300-301: Etropus microstomus GILL 1864 – 15 × Etropus longimanus NORMAN 1933 Figs. 296-299 Investigated otoliths: 5 otoliths (4 right side, fig. 296-297, 299; 1 left side, fig. 298) from off Rio de Janeiro, Brazil, ZMH Ot. 14.5.1994.49-52 (leg. BMNH 1913.12.4.311-20) and BMNH 1913.12.4. 311-20. Variability: As shown in the figures to this species, variations of the outline of the otolith are quite considerable, as are its proportions. In fact, it is difficult to find a single character to define the species by otoliths alone. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: E. longimanus E. crossotus. Its otoliths are pressed, more thickset and convex inner face. Also the shorter and wider. is quite similar to slightly more comexhibit a much less sulcus is somewhat Distribution: Southern Atlantic, coasts of Brazil and Argentina. Etropus microstomus GILL 1864 Figs. 300-301 syn. Citharichthys microps FOWLER 1911 156 303 302a 304 302c 302b Figs. 302-304: Etropus concaviventris n.sp. – 15 × Investigated otoliths: 2 otoliths (right side) from the Delaware Bay, Atlantic coast of North America, ZMH Ot. 14.5.1994.53 (leg. BMNH 1933.6.15.1) and BMNH 1933.6.15.1. Discussion: Otoliths of this species are easily recognized by their roundish outline (except for the concave postdorsal rim) and the rather wide and deep sulcus. Distribution: Atlantic coast of North America, from New England to Florida. Etropus concaviventris n.sp. Figs. 302-304 Name: Combination of concavus (lat.) = concave, and venter (lat.) = body, stomach; referring to the strongly concave postventral rim of the otolith. Holotype: Fig. 302, NMB 15896a. Type locality: Rio Gurabo river banks, Cibao Valley, northern Dominican Republic. Age: Cerrado Formation, Upper Miocene. Paratypes: 2 otoliths (figs. 303-304), topo- and stratitypic, NMB 15896b and NMB 16922. Diagnosis: Compressed otoliths with rounded pentagonal outline. Postdorsal portion higher than predorsal portion. Postventral rim distinctly concave. Inner face markedly convex. Description: Small, compressed, moderately thick otoliths with a rounded pentagonal outline. Dorsal rim rather rounded, highest posteriorly, ventral rim deeply bodied with distinct and long concave postventral portion, posterior tip short, pointed, situated slightly inframedianly, anterior tip blunt. Inner face: Rather strongly convex and smooth. Sulcus moderately long, horizontal, with completely fused colliculi, indistinctly “fusiform” in shape. Sulcus opening reduced, medial. Dorsal and ventral depressions rather shallow, moderately wide and connected around the caudal tip. Other views: Rims moderately sharp and smooth, postdorsal rim sometimes slightly crenulated. Outer face more or less smooth, flat. Side dimorphism: Not apparent. Ontogeny and variability: The smallest specimen is 1.5 mm long but does not differ significantly from the largest specimen of about 2.3 mm length. All specimens exhibit suitable diagnostic characters indicating that morphological maturity in this species is reached at relatively small otolith sizes. Variability is moderate, restricted to details in the expression of the dorsal rim, projection of the posterior tip and details in the outline of the sulcus. Discussion: E. concaviventris is readily recognized by the pronounced concavity of the postventral rim in combination with the shape of the dorsal rim and the rather convex inner face. It resembles species of the genus Etropus as well as Citharichthys. I have tentatively placed it in the former because of the strongly concave postventral rim and the somewhat reduced outline of the sulcus. Schwarzhans: Pleuronectiformes 157 Bothinae 7.6.5 Bothus Group Genera: Three genera – Bothus, Parabothus and Grammatobothus. This group is particularly well represented in the Indo-Pacific, but one of its genera – Bothus – is also found in the Mediterranean and the Atlantic. In addition, there is a single otolith based fossil record of the genus Grammatobothus from the Miocene of Europe (Poland, Paratethys). Definition and relationship: Together with the Arnoglossus, Monolene-Laeops and Engyprosopon Groups described later the Bothus Group constitutes the bulk of the genera placed into the subfamily Bothinae by NORMAN (1934), respectively Bothidae by HENSLEY & AHLSTROM (1984). The otoliths of the four groups in general are rather small, oval to roundish to rectangular in shape and with an ostial to pseudoostial sulcus opening. Dorsal and ventral depressions are usually well marked and deep and often well connected around the caudal tip. The ostium is almost always considerably longer than the cauda and slightly wider too. This combination of characters puts these groups well apart from the four other bothid otolith groups described before and in a way supports NORMAN’s concept to subdivide the Bothidae into two subfamilies. However, the line of subdivision according to otolith grouping slightly departs from NORMAN’s concept (not so much from HENSLEY & AHLSTROM’s concept), and this is being dealt with in the respective chapter to the Monolene-Laeops Group. The otoliths of the Bothus Group are quite thin, with a distinctly convex inner face and a rounded oval outline. In most instances, the sulcus opening is clearly ostial. It is this combination that distinguishes otoliths of the Bothus Group from the more compressed and massive otoliths of the other groups. However, the line of distinction is somewhat fluent and there are some genera, such as Parabothus, Crossorhombus or Engyprosopon, which could be placed in the one or the other group. In conclusion, the otoliths of both the Bothus Group as well as of the other three groups are characterized by a number of morphological reductions, which sometimes result in analytical Piscium Catalogus, Part Otolithi piscium, Vol. 2 uncertainties at all taxonomic levels. This is particularly true for the Arnoglossus and the Monolene-Laeops Group and is being discussed there in more detail. Bothus RAFINESQUE 1810 Type-species: Bothus rumulo RAFINESQUE 1810 (syn. B. podas) syn. Platophrys SWAINSON 1839 (type-species: Rhombus ocellatus) syn. Peloria COCCO 1844 (type-species: Peloria heckeli, syn. B. podas) syn. Coccolus BONAPARTE 1846 (type-species: Coccolus annectens, syn. B. podas) syn. Rhomboidichthys BLEEKER 1856 (type-species: Rhomboidichthys myriaster) subgenus syn. Psettylis ALCOCK 1890 (type-species: Psettylis pelucida – acc. to NORMAN 1934, postlarval spec. indet.) syn. Pseudocitharichthys WEBER 1913 (type-species: Citharichthys aureus, syn. B. pantherinus) syn. Platotichthys NICHOLS 1921 (type-species: Platotichthys chartes – acc. to NORMAN 1934, post-larval of B. lunatus) syn. Symboulichthys CHABANAUD 1927 (typespecies: Platophrys maculifer) Diagnosis: Relatively thin, small to very small otoliths with a rounded oval shape; ventral and dorsal rims gently curved, without major angles, posterior tip variable, rounded, blunt or projecting, anterior rim rounded or with short rostrum, then usually with faint excisura; index l:h 1.2 to 1.7. Otolith size rarely exceeding 3 mm, in fact otoliths are rather small in comparison to size of fish. Ostium slightly longer than cauda and slightly wider too. Sulcus narrow, deep, often with clear ostial opening. Excisura sometimes developed. Cauda terminating not very far from posterior tip of otolith. Colliculi separated, but distinction of ostium and cauda often very indistinct. Dorsal and ventral depressions narrow, but rather deep and well marked, indistinctly connected around caudal tip to form a circumsulcal depression. Inner face convex, not very smooth; outer face flat to slightly concave, with little ornamentation. Rims sharp, usually smooth, sometimes slightly undulating. 158 Measurements: l:h h:t ol:cl oh:ch con.i 2.3 3.0 2.7 3.0 3.0 1.3 1.3-1.8 1.5-1.6 1.3-1.5 1.2 1.4 1.2-1.5 1.2 1.2-1.3 1.2 3 3 4 2.8 2.5 subgenus Rhomboidichthys myriaster 1.25 2.7 mancus 1.30 nm 1.7-1.9 1.1 1.2-1.3 1.2-1.3 3 nm subgenus Bothus podas 1.40 pantherinus 1.55-1.65 ocellatus 1.60-1.70 constellatus 1.50-1.55 lunatus 1.60 Side dimorphism: Side dimorphism in this genus is quite inconspicuous and may vary from species to species. A series of specimens from B. podas figured by CHAINE (1936) indicate that right hand otoliths tend to be more regularly rounded in outline and left hand otoliths show a stronger tendency towards development of an excisura. This observation is also confirmed by otoliths of B. pantherinus, but in B. myriaster it is the other way round, and otoliths of B. ocellatus show virtually no side dimorphism. NOLF (1985) stated that some species of Bothus do not show any side dimorphism (example used was B. podas) and others a very strong side dimorphism (example was B. lunatus). His interpretation was based on a very compressed right hand otolith of B. lunatus (NOLF, 1985 – fig. 15 C2). A right hand specimen of the same species available to me does not show this habitus, but rather fits with the left hand specimen he figured. Judging from this, the compressed right side otolith of B. lunatus as figured by NOLF rather represents a singular case of teratological deformation than a valid case of side dimorphism. Sexual dimorphism: The fishes of the genus Bothus like several other Bothinae genera (Engyprosopon, Crossorhombus, Perissias, Parabothus and one species of Syacium) are well known for a sexual difference in the width of the interorbital region. The interorbital region in those genera is wider in males than it is in females and this curious feature attains its maximum development in certain species of the genus Bothus (= Platophrys auctt.). It may be expected that this development is also reflected in some kind of sexual dimorphism in otoliths. And indeed this seems to be the case with the genus Syacium (S. ovale – see respective entry). In the case of Bothus and the other genera mentioned presently available otolith material, unfortunately, is not sufficient for such an investigation. Ontogeny and variability: So far too few otoliths are known from this genus to allow for any analysis of ontogenetic changes. However, since otoliths in general are very small it seems that diagnostic maturity is reached already with relatively small specimens in the order of 1.5 to 2 mm. Judging from CHAINE’s (1936) figures of B. podas intraspecific variability is moderate and only concerns details of the outline of the otolith and expression of the excisura, both characters which are also touched by the effects of side dimorphism. Discussion: Bothus otoliths resemble both Parabothus and Grammatobothus otoliths. In the two latter genera the inner faces of the otoliths are less convex and the postventral angle is always quite well developed. In Parabothus the ostial opening is somewhat reduced, but this is also the case in certain Bothus species (see for instance B. ocellatus). The genus Bothus contains some 18 nominally valid species. Otoliths are known from 8 of them. From this it appears that at least two different morphologies can be recognized from otoliths. One group comprises relatively elongate, oval otoliths, mostly without excisura (except for B. lunatus), whereas the other group comprises roundish, compressed otoliths, which are extremely small in comparison to the size of the fishes from which they have been taken. Available generic names are attributed to the two groups in subgeneric ranking – the first would become the subgenus Bothus, the second the subgenus Rhomboidichthys. Realizing, however, that otoliths are only known from about half of the recent species of this genus one may expect more potential for such subdivisions. Species and distribution: 18 nominally valid species: B. podas, B. mellissi and B. guibei from the Mediterranean and East Atlantic, B. ocellatus, B. lunatus, B. maculiferus, B. robinsi and B. ellipticus from the West Atlantic, B. leopardinus and B. constellatus from the Pacific coast of America and B. mancus, B. pantherinus, B. bleekeri, B. myriaster, B. ovalis, B. tricirrhatus, B. ypsigrammus and B. assimilis from the Indo-West-Pacific. Thus the genus Bothus is one of the most widely distributed genera of Pleuronectiformes. NORMAN (1934) has explained this unusually wide distribution pattern of the genus by a prolonged early pelagic life adherent to the larval stage. Schwarzhans: Pleuronectiformes 159 305c 305a 306c 306a 305b 306b Fig. 305: Bothus (Bothus) podas (DELAROCHE 1809) – 15 × Figs. 306-307: Bothus (Bothus) pantherinus (RÜPPEL 1830) – 15 × Bothus (Bothus) podas (DELAROCHE 1809) Fig. 305 syn. Pleuronectes argus RISSO 1810 syn. Bothus rumulo RAFINESQUE 1810 syn. Solea rhomboides RAFINESQUE 1810 syn. Bothus diaphanus RAFINESQUE 1814 ?syn. Rhombus candidissimus RISSO 1820 syn. Rhombus gesneri RISSO 1826 syn. Rhombus heterophthalmus BENNETT 1831 syn. Rhombus rhomboides BONAPARTE 1833 syn. Rhombus maderensis LOWE 1834 syn. Rhombus serratus VALENCIENNES 1843 syn. Peloria heckelii COCCO 1844 ?syn. Coccolus annectens BONAPARTE 1846 Investigated otoliths: 2 otoliths (right and left side) from off Zanzibar, ZMH Ot. 16.5.1994.2-3 (leg. ZMH 19925). Discussion: Otoliths of B. pantherinus are quite similar to those of B. podas, but are more elongate and thin. Distribution: Indian Ocean from East Africa and the Red Sea to Indonesia, Australia and the Pacific. Bothus (Bothus) ocellatus (AGASSIZ 1831) Figs. 308-309 Investigated otoliths: 1 otolith (right side) from off Calabria, Italy, ZMH Ot. 16.5.1994.1 (leg. ZMH 19932). syn. Rhombus bahianus CASTELNAU 1855 syn. Platophrys nebularis JORDAN & GILBERT 1885 ?syn. Bothus atlanticus KYLE 1913 Discussion: Otoliths of B. podas are more compressed and more regularly rounded than those of the other species investigated. Investigated otoliths: 2 otoliths (right and left side) from off Georgia, USA, ZMH Ot. 16.5.1994.45 (leg. Fitch). Distribution: Mediterranean and East Atlantic, from Portugal to Angola and westward to Madeira and the Canaries. Discussion: B. ocellatus is easily recognized by its anteriorly pronounced dorsal rim and the somewhat reduced ostial opening. Bothus (Bothus) pantherinus (RÜPPEL 1830) Figs. 306-307 syn. Rhombus parvimanus BENNETT 1832 syn. Rhombus sumatranus BLEEKER 1851 ?syn. Passer marchionessarum VALENCIENNES 1855 syn. Pleuronectes lunulatus JOUAN 1861 ?syn. Citharichthys aureus DAY 1877 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Atlantic coast of America, from New York to Rio de Janeiro. Bothus (Bothus) constellatus (JORDAN & GOSS 1889) Figs. 310-313 Investigated otoliths: 4 otoliths (3 right and one left) from the Galapagos Isl., ZMH Ot. 2.1.1995.1315 (leg. BMNH 1938.12.12.163-5) and BMNH 1938.12.12.163-5. 160 309a 309c 308 309b 310 311 312a 312c 312b 313 Figs. 308-309: Bothus (Bothus) ocellatus (AGASSIZ 1831) – 15 × Figs. 310-313: Bothus (Bothus) constellatus (JORDAN & GOSS 1889) – 15 × Discussion: Quite similar to B. podas but more elongate. Otoliths of B. pantherinus are more thin and less regularly rounded in outline. Those of B. ocellatus from the Atlantic coast of North America are somewhat narrowed posteriorly. NORMAN (1934) doubted B. constellatus to be distinct from B. leopardinus (GÜNTHER 1862) from the Pacific coast of tropical America. Of the latter species otoliths so far are missing for comparison. Distribution: Panama Bay (Pacific) and Galapagos Islands. Bothus (Bothus) lunatus (LINNAEUS 1758) Fig. 314 syn. Pleuronectes argus BLOCH 1783 ?syn. Pleuronectes surinamensis SCHNEIDER 1801 syn. Platotichthys chartes NICHOLS 1921 a b c Fig. 314: Bothus (Bothus) lunatus (LINNAEUS 1758) – 15 × Investigated otoliths: 1 otolith (right side) from off St. Thomas, Caribbean, ZMH Ot. 16.5.1994.6 (leg. ZMH 19894). Schwarzhans: Pleuronectiformes 161 316a 315 316c 317 316b Figs. 315-316: Bothus (Rhomboidichthys) myriaster (TEMMINCK & SCHLEGEL 1846) – 15 × Fig. 317: Bothus (Rhomboidichthys) mancus (BROUSSONET 1782) – 15 × Discussion: The otolith of B. lunatus is very thin and fragile, with a rather strongly convex inner face, a deep excisura and a rather pronounced postdorsal angle. have been quite similar to those of B. myriaster, may be slightly more elongate. NORMAN (1934) regarded both species as closely related, probably synonymous. Distribution: Atlantic coast of America, from Florida to northern Brazil and eastward to Fernando Noronha Isl. Distribution: Coasts of India to Burma and Amirantes Islands. Bothus (Rhomboidichthys) myriaster (TEMMINCK & SCHLEGEL 1846) Figs. 315-316 syn. Platophrys circularis FRANZ 1910 Investigated otoliths: 2 otoliths (left and right) from off Formosa, ZMH Ot. 2.1.1994.17 (leg. BMNH 1933.6.12.4) and BMNH 1933.6.12.4. Discussion: A small, easily recognized thin otolith with almost circular outline, convex inner face and concave outer face. All rims are intensely crenulated. Distribution: Coasts of China, Japan, Formosa and Indo-China. Bothus (Rhomboidichthys) ovalis (REGAN 1908) Remarks: The only otolith extracted from a fish caught off India (BMNH 1928.3.20.135) was too much eroded by formalin to warrant a figure. Nevertheless, it was apparent that the otolith must Piscium Catalogus, Part Otolithi piscium, Vol. 2 Bothus (Rhomboidichthys) mancus (BROUSSONET 1782) Fig. 317 syn. Pleuronectes spinosus SCHNEIDER 1801 syn. Rhombus macropterus QUOY & GAIMARD 1824 syn. Pleuronectes pictus FORSTER 1844 syn. Rhombus pavo BLEEKER 1855 syn. Platophrys smithi RENDAHL 1921 Investigated otoliths: 1 otolith (right side) from the Tarawa lagoon, Gilbert & Ellice Islands, Polynesia, BMNH 1969.8.26.239-302. Discussion: The only otolith available is somewhat eroded, in particular the sulcal portion of the inner face. It is characterized by its extremely small size compared to the size of the fish. B. mancus differs from B. myriaster in the rather flat ventral rim and the lack of marginal crenulation. Distribution: Widely distributed in the IndoWest-Pacific from China to the Micronesian and Polynesian Islands to the Maldives. 162 319a 318 319c 320 319b Figs. 318-320: Parabothus chlorospilus (GILBERT 1905) – 15 × Parabothus NORMAN 1931 Type-species: Arnoglossus polylepis ALCOCK 1889 being more elongate and always showing a clear sulcus opening. Diagnosis: Moderately thin, small otoliths with an irregular oval shape; ventral rim gently curving, dorsal rim with rounded predorsal and pronounced postdorsal angles, straight and horizontal in between, posterior tip blunt or faintly pointed, anterior rim rounded or blunt, without marked rostrum, nor excisura; index l:h about 1.5. Otolith size probably not exceeding 3 mm. Ostium longer than cauda and slightly wider too. Sulcus moderately narrow, deep, with slightly reduced opening. Cauda terminating not very far from posterior tip of otolith. Colliculi separated, distinction usually well marked. Dorsal and ventral depressions rather deep and well marked, indistinctly connected around caudal tip to form a circumsulcal depression. Inner face slightly convex, not very smooth; outer face flat, with little ornamentation. Rims moderately sharp, smooth. Species and distribution: NORMAN (1934) and MASUDA et al. (1984) reported 4 species – P. polylepis, P. chlorospilus, P. coarctus, P. kiensis – plus 4 somewhat problematical additional species which were based on unique holotypes – P. amaokai, P. taiwanensis, P. violaceus, P. malhensis. All species are from the Indo-Pacific. Otoliths are only known from a single species, P. chlorospilus. Parabothus chlorospilus (GILBERT 1905) Figs. 318-320 syn. Platophrys inermis GILBERT 1905 Investigated otoliths: 3 otoliths (two right side and one left side) from off Hawaii, ZMH Ot. 16.5.1994.7-9 (leg. Fitch). Discussion: See entry to genus. Measurements: chlorospilus l:h 1.45-1.50 h:t 2.5 ol:cl 1.3-1.6 oh:ch 1.1-1.3 con.i 3.5 Side dimorphism: Like in the related genus Bothus side dimorphism is very indistinct. It so seems that the reduction of the sulcus opening is stronger in right hand than in left hand otoliths. Variability: Some of the proportions can be quite variable, particularly as far as the sulcus is concerned. Also the posterior tip of the otolith can be pointed or blunt and nearly vertically cut. Discussion: Close to Bothus (see respective entry) and Grammatobothus. The latter differs in Distribution: Hawaiian Islands. Grammatobothus NORMAN 1926 Type-species: Platophrys polyophthalmus BLEEKER 1866 Diagnosis: Moderately thin, small to medium sized otoliths with an elongated rectangular shape; ventral rim shallow, gently curving, dorsal rim straight, horizontal, with marked pre- and postdorsal angles, posterior tip blunt, anterior rim blunt, with faint excisura and short rostrum; index l:h about 1.7. Otolith size up to 4 mm and possibly more. Schwarzhans: Pleuronectiformes 163 322a 322c 321 322b Figs. 321-322: Grammatobothus polyophthalmus (BLEEKER 1866) – 15 × Ostium slightly longer than cauda and slightly wider too. Sulcus moderately narrow, deep, with clear ostial opening. Cauda terminating not very far from posterior tip of otolith. Colliculi separated, but distinction of ostium and cauda often very indistinct. Dorsal and ventral depressions narrow, but rather deep and well marked, more or less connected around caudal tip to form a circumsulcal depression. Inner face slightly convex, not very smooth; outer face flat, with little ornamentation. Rims moderately sharp, usually smooth, sometimes slightly undulating. Measurements: l:h polyophthalmus 1.70 †radwanskae 1.70-1.75 †awamoaensis 1.80 h:t 2.8 2.8 2.9 ol:cl 1.5-1.8 0.8-1.0 1.45 oh:ch 1.2-1.3 1.1-1.2 1.1 con.i 5 4 4 Side dimorphism: Not apparent. Variability: Variations concern details of the expression of the dorsal rim, development of the rostrum and proportions of the sulcus. Discussion: Close to Bothus and Parabothus (see respective entries). Species and distribution: Grammatobothus is known from 3 recent species from the Indo-Pacific – G. polyophthalmus, G. pennatus, G. krempfi – and two fossil species, one from the Middle Miocene of Poland (Paratethys) – G. radwanskae – the other from the Lower Miocene of New Zealand – G. awamoaensis. Grammatobothus polyophthalmus (BLEEKER 1866) Figs. 321-322 syn. Rhomboidichthys angustifrons GÜNTHER 1880 Investigated otoliths: 2 otoliths (right and left side) from Pukhet, Thailand, ZMH Ot. 16.5. 1994.10-11 (leg. ZMUC P 853412). Discussion: The otoliths of G. polyophthalmus are somewhat smaller than those of the fossil G. radwanskae, but otherwise are quite similar except for the sulcus proportions. Distribution: From the Indian Ocean through the Malay Peninsula and Indonesia to Australia. Grammatobothus radwanskae n.sp. Figs. 323-325 syn. genus Bothidarum sp. – RADWANSKA 1992: fig. 159, pl. 36, fig. 11-12 Name: In honor to Mrs. U. Radwanska (Warsaw) and her outstanding monograph on otoliths from the Polish Miocene. Holotype: Fig. , ZPalUW/Rak-441. Type locality: Korytnica, southern Holy Cross Mountains, southern Poland. Age: Korytnica Clay, Badenian, Middle Miocene. Paratypes: 2 otoliths, topo-and stratitypic, ZPalUW/Rak-442. Diagnosis: Elongate, moderately thickset otoliths with roughly rectangular outline. Excisura and short rostrum present. Sulcus deep, long, with Piscium Catalogus, Part Otolithi piscium, Vol. 2 164 323a 323c 323b 325 324 Figs. 323-325: Grammatobothus radwanskae n.sp. – 15 × clear ostial opening. Dorsal and ventral depression distinct, deep. may be smaller in right hand otoliths than in left hand otoliths. Description: Outline: Rather elongate, moderately large and massive otoliths with roughly rectangular outline. Dorsal rim straight, horizontal, somewhat undulating, with rounded predorsal and prominent postdorsal angles. Ventral rim shallow, gently curving. Posterior tip blunt, nearly vertically cut. Anterior rim blunt, with excisura and short rostrum. Inner face: Moderately convex and not very smooth. Sulcus long, median, deep, clearly opening anteriorly, posteriorly terminating not very far from posterior tip of otolith. Partition into ostium and cauda indistinct, but ostium usually not longer than cauda, sometimes considerably shorter. Dorsal and ventral depressions narrow, deep, well marked, more or less connected around caudal tip. Other views: Rims moderately sharp and mostly smooth. Outer face smooth, flat to very slightly concave. Variability: Ornamentation of the otolith rims and proportions of the sulcus seem to be somewhat variable. Side dimorphism: Not apparent, but index ol:cl Discussion: Otoliths of G. radwanskae are quite similar to those of the recent G. polyophthalmus. The most obvious character to distinguish the two species is the proportion of ostium to cauda length. In G. polyophthalmus the ostium is much longer than the cauda, whereas in G. radwanskae it is either shorter or of about the same length. Grammatobothus awamoaensis n.sp. Figs. 326 Name: Named after the type location – Awamoa Creek – in New Zealand. Holotype: Fig. 326, NZGS. Type locality: Awamoa Creek, Otago, New Zealand South Island. Age: Altonian, Lower Miocene. Schwarzhans: Pleuronectiformes 165 Diagnosis: Elongate, rather thin otolith with rounded rectangular outline. No excisura, short rostrum present. Sulcus moderately deep, long, with slightly reduced ostial opening. Dorsal and ventral depression distinct, deep. Description: Outline: Rather elongate, moderately large and rather thin otolith with rounded rectangular outline. Dorsal rim straight, horizontal, with rounded predorsal and prominent postdorsal angles. Ventral rim more deeply, gently curving. Posterior tip rounded. Anterior rim ventrally pointed, with short rostrum. Inner face: Moderately convex and not very smooth. Sulcus long, slightly supramedian, moderately deep, anterior opening somewhat reduced. Partition into ostium and cauda distinct, ostium somewhat longer than cauda. Dorsal and ventral depressions narrow, deep, well marked, more or less connected around caudal tip. Other views: Rims sharp and smooth. Outer face smooth, flat to very slightly concave. Discussion: The otolith of G. awamoaensis is more elongate than those of the two other species and also characterized by its somewhat reduced sulcus opening and the thin appearance. 7.6.6 Arnoglossus Group Genera: In this group I have tentatively placed 6 genera – Neolaeops, Arnoglossus, Caulopsetta, Lophonectes, Psettina and Taeniopsetta. Most of these genera are concentrated in the Indo-Pacific, but the very large genus Arnoglossus is also well known from the East Atlantic and the Mediterranean. It is not reported from the shores of the Americas. Otoliths are known from all genera. Fossil records of Arnoglossus are common in Europe, NW-Africa and New Zealand and date well back into Eocene times. Caulopsetta and Taeniopsetta are also known from the Miocene of New Zealand. Definition and relationship: Otoliths of the Arnoglossus Group are rather compact and small, compressed to moderately elongate and rectangular to rounded rectangular in outline. The sulcus typically is deep and somewhat inclined. Its opening is slightly reduced in most instances. Dorsal and ventral depressions are deep and more or less well connected around the caudal tip. The Piscium Catalogus, Part Otolithi piscium, Vol. 2 c a b Fig. 326: Grammatobothus awamoaensis n.sp. – 15 × inner face in most instances is rather flat, but there are few cases where it is markedly convex. The somewhat inclined sulcus in combination with the usually relatively flat inner face and the more or less rectangular outline are the main characters that distinguish otoliths of the Arnoglossus Group from the supposed related groups. The other extreme is found in the Bothus Group with its more gently curving outline, the horizontal sulcus (often with a clear ostial opening) and the markedly convex inner face. Otoliths of the Monolene-Laeops Group are similar to those of the Arnoglossus Group in their compact and compressed appearance, including the flat inner face. Differing, however, these otoliths do not show much of an inclined sulcus and also the outline is more trapezoidal than rectangular. Otoliths of the Engyprosopon Group finally exhibit a combination of characters of the Arnoglossus and the Bothus Groups. With the latter they share the strongly convex, often rather smooth inner face, with the Arnoglossus Group the compact appearance and the (rounded) rectangular outline. Also the sulcus sometimes is slightly inclined. However, as already stated in the introductory note to the Bothus Group, otoliths of all four groups are characterized by certain trends in reduction of the morphology. Therefore, definition and delimitation of these groups is somewhat fluent and much less certain than for the other bothid otolith groups. As it stands now, the differentiation of the Bothus, Arnoglossus, Monolene-Laeops and the Engyprosopon Groups must be viewed as a very tentative one. It should be noted, however, that NORMAN in his analysis of the bothids also assumed the genera here included in the Arnoglossus Group to be closely related, but except for Taeniopsetta. 166 inclination of the sulcus and the presence of a very small rostrum. In fact, Neolaeops could also be regarded as a plesiomorphic representative of the Monolene-Laeops Group. Morphologically, it bridges between the two groups. Species and distribution: Neolaeops contains but a single recent species – N. microphthalmus – which is widely distributed throughout the Indo-WestPacific, from South Africa to Japan. NORMAN (1934) tentatively included N. microphthalmus within the genus Arnoglossus as well as A. intermedius, which is now placed in the monospecific genus Asterorhombus. a c b Fig. 327: Neolaeops microphthalmus (VON BONDE 1922) – 15 × Neolaeops AMAOKA 1969 Type-species: Laeops microphthalmus VON BONDE 1922 Diagnosis: Relatively thick, small otoliths with a rounded rectangular outline; ventral rim shallow, gently curved, dorsal rim flat, horizontal, with rounded pre-and postdorsal angles, posterior tip blunt, nearly vertically cut, anterior rim blunt, with incipient short rostrum, but without excisura; index l:h about 1.4. Otolith size about 3 mm. Ostium longer than cauda and slightly wider too. Sulcus narrow, moderately deep, very slightly inclined, with a slightly reduced ostial opening. Cauda terminating at some distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions moderately deep and well marked, connected around caudal tip to form a circumsulcal depression. Inner face almost flat in horizontal direction and only slightly convex in vertical direction, rather smooth; outer face convex, smooth. Rims moderately sharp, slightly and irregularly undulating. Measurements: microphthalmus l:h 1.45 h:t 2.7 ol:cl 1.3 oh:ch 1.3 s.i.a. 5° con.i 6 Side dimorphism: Not known. Discussion: Within the Arnoglossus Group the otolith of Neolaeops probably represents the most plesiomorphic morphology. This is indicated by the rounded rectangular outline, the very feeble Neolaeops microphthalmus (VON BONDE 1922) Fig. 327 Investigated otoliths: 1 otolith (right side) from off Kochi, Japan, ZMH Ot. 16.5.1994.12 (leg. Sasaki). Discussion and distribution: See entry to genus (monospecific genus). Arnoglossus BLEEKER 1862 Type-species: Pleuronectes arnoglossus SCHNEIDER 1801 (syn. A. laterna) syn. Bascanius SCHIODTE 1868 (type-species: Bascanius taedifer, syn. A. rueppellii) syn. Anticitharus GÜNTHER 1880 (type-species: Anticitharus polyspilus) syn. Charybdia FACCIOLA 1885 (type-species: Peloria rueppellii) syn. Scidorhombus TANAKA 1915 (type-species: Scidorhombus pallidus) syn. Kyleia CHABANAUD 1931 (type-species: Arnoglossus thori) syn. Dollfusiana CHABANAUD 1933 (type-species: Peloria rueppellii) syn. Dollfusetta WHITLEY 1950 (substitute for Dollfusiana) Diagnosis: Mostly thickset, small and compact otoliths with a rectangular or rounded rectangular outline; ventral rim shallow, gently curved to almost straight and horizontal, dorsal rim flat, horizontal, with rounded pre-and postdorsal angles, postdorsal angle usually more strongly Schwarzhans: Pleuronectiformes 167 pronounced, posterior tip blunt, nearly vertically cut, anterior rim blunt, without rostrum; index l:h 1.1 to 1.7. Otolith size up to 3.5 – 4 mm. Ostium longer than cauda and slightly wider too. Sulcus narrow, deep to very deep, inclined, usually with a slightly reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated, deepened. Dorsal and ventral depressions deep to very deep, well marked, connected around caudal tip to form a circumsulcal depression. Inner face almost flat to slightly convex in horizontal direction and only slightly convex in vertical direction, not smooth; outer face flat to convex, mostly smooth. Rims moderately sharp or thickened, smooth to slightly and irregularly undulating. Measurements: laterna macrostoma thori grohmanni imperialis †holleri †taureri †kokeni †quadratus capensis rueppellii tapeinosoma waitei aspilos †lapierrei †prudhommae †extremus †novus †longus †grenfelli debilis dalgleishi l:h 1.20-1.40 1.50-1.60 1.45-1.65 1.70-1.85 1.55-1.75 1.15-1.30 1.10-1.30 1.10-1.20 1.25-1.30 1.65 1.45 1.25-1.35 1.35 1.20 1.35 1.10 1.50 1.15-1.20 1.35-1.55 1.35-1.45 1.30 1.30-1.40 h:t 2.8 2.0-2.6 2.5 2.5 2.3 2.6-2.8 2.5-2.6 2.4-2.7 2.0-2.3 2.0 nd 2.5 2.7 2.7 2.0 3.2 nd 2.2 2.2 2.5-2.6 3.4 3.2 ol:cl 1.8-2.2 1.5-1.8 1.5-1.7 1.1-1.5 1.4-1.5 1.4-1.7 1.5-2.0 1.8-2.2 1.3-1.7 1.6 2.2 1.8-2.0 1.7 1.6 1.5 1.8 1.0 1.6-2.0 1.4-1.9 1.4-1.5 1.4 1.5-1.8 oh:ch 1.2-1.3 1.0-1.3 1.1-1.3 1.2-1.3 1.0-1.1 1.2-1.4 1.2-1.4 1.2-1.3 1.3-1.5 1.1 1.2 1.1 1.5 1.3 1.1 1.2 1.0 1.1-1.2 1.1 1.1-1.2 1.2 1.1 s.i.a. con.i 10° 5.5 5° 5.5 5-10° 4 5° nm 5° 4 10° 3 10-15° 5 10-15° -5 5-10° 5-6 5° 2.5 20° nd 20° 3.5 10° 3.5 15° 4.5 25° 2.8 25° 4 25° nd 25° 2.8 10° 3.5 10° 4-5 10° 6 10° 5.5 Side dimorphism: Not apparent. Ontogeny and variability: Ontogenetic changes in the otoliths of this genus are quite considerable and so is intraspecific variability. Due to the somewhat “reduced” morphological habitus of the otoliths relatively few features are left for diagnosis and differentiation of species. Many of them concern outline and proportions of the otoliths, and these are the very characters most strongly affected by intraspecific variations. In several instances relatively large series of specimens will be needed to reliably distinguish between otoliths of related species (see for instance entries to A. laterna or A. imperialis). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Likewise, ontogenetic effects need to be dealt with in great care. Small otoliths of less than 1.5 mm (sometimes 2 mm) of length are often so much generalized in appearance that related species can not be distinguished (see entries to A. longus and A. novus). Again it is mostly the outline that is affected. There are also few cases, where juvenile otoliths look quite different from adults due to additional changes in the marginal ornamentation (see entry to A. quadratus). Unfortunately, ontogenetic (and erosive) effects have not always been taken into consideration in the descriptions of the many fossil species. This has led to a rather chaotic taxonomic situation in fossils, particularly as far as secondary references are concerned. I was not able to check all the various secondary references in literature and therefore have restricted myself to reviewing mainly primary references plus a certain selection of secondary references when available and important for faunal reconstructions. The aim was to establish diagnoses for each fossil species based on type material and make them as detailed and reliable as possible. I hope that this will help to more accurate secondary references in future investigations. Discussion: The otolith morphologies found in the genus Arnoglossus are quite diverse. According to NORMAN (1934) this also seems to be the case for the fishes themselves which in the past has led some authors to subdivide Arnoglossus into more genera or subgenera. NORMAN stated that “the genus Arnoglossus still remains a somewhat heterogenous group, but I (NORMAN) am unable to find any valid reasons for its further subdivision”. Results from otolith analyses are similar. Some species morphologically are more different from the “core” of the genus, such as A. rueppellii, A. capensis, A. tapeinosoma or A. dalgleishi, but overall the patterns are to mosaic in nature to warrant their separation from Arnoglossus based on otoliths alone. It seems, however, that the European and East Atlantic species (except for A. rueppellii) form a cluster of species and the Indo-Pacific ones one or two other clusters (for discussions see entries to species). In differentiating the two main clusters the degree of sulcal inclination could become a valuable character. Otoliths of Arnoglossus resemble those of the other genera in the group and differentiation on the generic level is not always easy, even to gen- 168 329 328a 328c 328b 330a 330b 331 332 Figs. 328-332: Arnoglossus laterna (WALBAUM 1792) – 15 × era of presumably related otolith groups such as Trichopsetta or Monolene of the Monolene-Laeops Group. The most useful character for recognition of Arnoglossus otoliths probably is the combination of the rather regularly rectangular outline and the inclined sulcus. Species and distribution: According to NORMAN (1934) and HENSLEY (1986) there may be some 19 to 24 recent species in the genus (excluding the species placed in the genera Neolaeops, Asterorhombus and Caulopsetta). The following list containing 29 species may not be complete. 7 species are recorded from European and African waters – A. capensis, A. grohmanni, A. imperialis, A. laterna, A. macrostoma, A. rueppellii and A. thori – and 22 from the Indo-West-Pacific and Southern Ocean – A.andrewsi, A. arabicus, A. armstrongi, A. aspilos, A. bassensis, A. dalgleishi, A. debilis, A. elongatus, A. fisoni, A. japonicus, A. kotthausi, A. maculipinnis, A. marisrubri, A. muelleri, A. multirastris, A. oxyrhynchus, A. polyspilus, A. profundus, A. sayaensis, A. tapeinosoma, A. tenuis and A. waitei. Otoliths are known from 12 species. 2 recent species are also known as fossils from the Pliocene of the North Sea Basin – A. laterna and A. imperialis. In addition there are 10 valid otolith based fossil species of Arnoglossus ranging in age from Eocene to Pliocene – 6 species from Europe and North Africa (A. kokeni, A. lapierrei, A. holleri, A. prudhommae, A. quadratus, A. taureri) and 4 from New Zealand (A. extremus, A. grenfelli, A. longus, A. novus). Arnoglossus laterna (WALBAUM 1792) Figs. 328-332 syn. syn. syn. syn. syn. syn. Pleuronectes arnoglossus SCHNEIDER 1801 Pleuronectes diaphanus SHAW 1803 Pleuronectes leotardi RISSO 1810 Rhombus nudus CUVIER 1817 Pleuronectes conspersus CANESTRINI 1862 Arnoglossus laterna microstoma KYLE 1913 Investigated otoliths: 5 otoliths, 2 otoliths (right and left side, figs. 328-329) from the North Sea, ZMH Ot. 16.5.1994.13-14 (coll. Schwarzhans), 1 otolith (right side, fig. 330) Bretagne, France, ZMH Ot. 16.5.1994.15 (leg. FBH), 2 otoliths (right and left side) from the Mediterranean, SMF 7620, 2 otoliths (figs. 331-332) from the Lower Pliocene (Katendijkian) of Antwerp, Belgium, coll. SCHWARZHANS. Variability: Otoliths of A. laterna have been figured during several occasions, the most complete Schwarzhans: Pleuronectiformes 169 333a 334a 333b 334b Figs. 333-334: Arnoglossus macrostoma KYLE 1913 – 15 × series being the one of CHAINE (1936). The species is well known for its rather large degree of intraspecific variations. Features of the outline and otolith proportions are heavily affected. Extreme phenotypes, when isolated, may not always be distinguishable from those of related species such as A. thori or A. imperialis. However, the lack of differentiation between A. laterna and A. macrostoma in many collections and in literature as well may well play a part in what seems to be an overly variability spectrum. In any case, the range of variations seen in such a well known species as A. laterna should be kept in mind when dealing with fossil otoliths of this genus. Discussion: Otoliths of A. laterna exactly look like “the average Arnoglossus otolith” to which many of the other species, particularly from Europe and North Africa, are traditionally being compared to. Distribution: Eastern Atlantic, from Middle Norway to Cape Blanc (Mauritania) and throughout the Mediterranean. Also known as fossils from the Pliocene of Belgium. Variability: One of the two specimens is more thickset, the other one shows a slightly undulating ventral rim. Discussion: In most ichthyological literature A. macrostoma is regarded as a junior synonym of A. laterna. NORMAN (1934) discussed this aspect and gave his reasoning why he selected to regard it as a separate species. After having extracted otoliths from specimens identified by him as A. macrostoma it seems that otoliths are somewhat different from those of “typical” A. laterna specimens as well. They are somewhat more elongate and more rounded in outline. It appears that part of the unusually high degree of intraspecific variability reported for otoliths of A. laterna may be due to lack of differentiation of the two species. Distribution: Restricted to the Mediterranean. Arnoglossus thori KYLE 1913 Fig. 335 syn. Arnoglossus moltoni TORCHIO 1961 Arnoglossus macrostoma KYLE 1913 Figs. 333-334 Investigated otoliths: 2 otoliths (right side) from off Dalmatian, Mediterranean, ZMH Ot. 16.5.1994.16 (leg. BMNH 93.2.28.29-30) and BMNH 93.2.28.29-30. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 6 otoliths (4 right and 2 left) from the Adriatic coast of Italy, ZMH Ot. 2.1.1995.18 (leg. BMNH 90.1.21.69-78) and BMNH 90.1.21.69-78. Discussion: From the specimens extracted from the BMNH collection only the one figured is well preserved. Also judging from BAUZA-RUL- 170 LAN’s (1957) figures otoliths of A. thori are quite similar to those of A. grohmanni or A. imperialis, all three being species with rather elongate otoliths. Those of A. thori usually show some kind of an irregularly undulating dorsal rim, often with a notch at the posterior tip of the otolith, and an obtuse midventral angle. However, I doubt that the three species can always be distinguished reliably by means of otoliths. Distribution: Western Mediterranean and East Atlantic, from Ireland to southernmost Morocco. Arnoglossus grohmanni (BONAPARTE 1837) Fig. 336 syn. Arnoglossus kessleri SCHMIDT 1915 Investigated otoliths: 1 otolith (right side) from the Adria, Yugoslavia, SMF 13100. Discussion: Larger series of this species have been figured by CHAINE (1936) and BAUZARULLAN (1957). From this it seems that the otoliths of A. grohmanni are the most elongate to be found in Arnoglossus. However, this remains the only character to distinguish the species from A. imperialis. A certain degree of overlap apparently exists and I doubt that the two species will always be distinguishable by means of otoliths. Distribution: Mediterranean and Black Sea. Arnoglossus imperialis RAFINESQUE 1810 Figs. 337-339 syn. Arnoglossus lophotes GÜNTHER 1862 ?syn. Arnoglossus blachei STAUCH 1965 (acc. to HENSLEY, 1986) Investigated otoliths: 6 otoliths, 3 otoliths (right side, fig. 337-338) from Great Britain, ZMH Ot. 16.5.1994.17-18 (leg. BMNH 92.10.11.3-5) and BMNH 92.10.11.3-5, 2 otoliths (right and left side) from the Scyllies, ZMH Ot. 16.5.1994.19 (leg. SMF 15885) and SMF 15885, 1 eroded otolith (ident. as A. blachei), 07°29’N/13°38’W, BMNH 1962.6.18. 36-45; 1 otolith (fig. 339) from the Lower Pliocene (Katendijkian) of Antwerp, Belgium. Ontogeny and variability: The outline of the otoliths of this species is rather constant, but the length to height ratio seems to be quite variable. Also larger specimens are continuously becoming more elongate. Discussion: A. imperialis is one of the European species of Arnoglossus with rather elongate otoliths, like A. macrostoma, A. thori and A. grohmanni. Seemingly they are the ones with the most regular rectangular outline and they do not seem to become as elongate as the ones of A. grohmanni. Nevertheless, distinction of otoliths of these species may not always be possible, in particular when dealing with isolated specimens. A single eroded specimen extracted from a fish identified as A. blachei was too much eroded to be figured. Its general appearance, however, confirms HENSLEY’s (1986, in SMITH & HEEMSTRA) view of this species representing a junior synonym of A. imperialis. Together with the three species mentioned above and A. laterna A. imperialis seems to form a cluster of species within the genus Arnoglossus. All these species are remarkable for their relatively flat inner face and the rather low degree of inclination of the sulcus. In addition, there are certain fossil species from the same geographic area which also seem to fit within this cluster. They are described in the following – A. holleri, A. taureri, A. kokeni and A. quadratus. Distribution: Western Mediterranean and East Atlantic, from Scotland southward to Angola. Arnoglossus holleri WEINFURTER 1952 Figs. 341-352 syn. Arnoglossus holleri WEINFURTER 1952 – WEINFURTER 1952: pl. 4, fig. 4 syn. Arnoglossus miocenicus WEILER 1962 – WEILER 1962: fig. 1, 18a-20 syn. Arnoglossus miocenicus – STEURBAUT 1979: pl. 11, fig. 12-14 ?syn. Arnoglossus sp. – NOLF & CAPPETTA 1980: pl. 3, fig. 15-16 syn. Arnoglossus sp. STEURBAUT & JONET 1981: pl. 4, fig. 6 syn. Arnoglossus sp. – STEURBAUT 1984: pl. 34, fig. 17-22 syn. Arnoglossus sp.2 – RADWANSKA 1992: fig. 158, pl. 38, fig. 1-3 Schwarzhans: Pleuronectiformes 171 335a 336 335b 337a 338 337b 339a 339b 340a 340b 340c Fig. 335: Arnoglossus thori KYLE 1913 – 15 × Fig. 336: Arnoglossus grohmanni (BONAPARTE 1837) – 15 × Figs. 337-339: Arnoglossus imperialis RAFINESQUE 1810 – 15 × Fig. 340: Arnoglossus capensis BOULANGER 1898 – 15 × Investigated otoliths: About 50 otoliths, figured specimens are: holotype of A. holleri (fig. 341), Badenian, Middle Miocene, Wetzelsdorf in Graz Basin, Austria (LMJ); 1 otolith (fig. 342), Badenian of Sooß, Vienna Basin, Austria (coll. Schwarzhans); 5 otoliths (figs. 343-346), Badenian, Middle Miocene, Korytnica, Poland Piscium Catalogus, Part Otolithi piscium, Vol. 2 (ZPalUW/Rak 434, 435, 437); 6 otoliths (figs. 347349), Burdigalian, Lower Miocene, Costa di Caparica near Lisbon, Portugal (coll. Schwarzhans); 3 otoliths (figs. 350-352), Hemmoorian and Reinbekian, Lower to Middle Miocene, well Lüllingen, NW-Germany (coll. Wienrich). 172 Ontogeny and variability: This is a relatively small species. Diagnostic maturity seems to be reached with otoliths of about 1.5 mm length. Smaller otoliths are extremely generalized and can only be identified in the context of sufficient ontogenetical sequences. Variability is rather moderate, mainly concerning details of the outline and otolith proportions. Discussion: These small otoliths are relatively compressed and somewhat “roundish” in outline. Otherwise they are similar to the recent A. laterna and the parallelly occurring A. taureri. The indistinct, roundish appearance and the small size of the otoliths has led otolith specialists in previous publications to regard them as some kind of unidentifiable juvenile forms. This interpretation is tempting, of course, but now that a large series of specimens is available it becomes obvious that they rather represent a small species. Nevertheless, it may at times become difficult to distinguish A. holleri from juveniles of other species, particularly so in isolated findings. – The typespecimens of WEILER’s A. miocenicus from the Middle Miocene of the North Sea Basin has not been available for review. However, newly collected material from the same area and strata (figs. 350-352) prove that this nominal species should be regarded as a junior synonym of A. holleri. Distribution: Lower and Middle Miocene of the Paratethys (Poland and Austria), the European Atlantic Basins (Portugal and western France) and the North Sea Basin (NW-Germany). Arnoglossus taureri (WEINFURTER 1952) Figs. 353-359 syn. Solea taureri WEINFURTER 1952 – WEINFURTER 1952: pl. 2, fig. 12-13 syn. Solea aff. taureri – SMIGIELSKA 1966: pl. 15, fig. 10-11 syn. Arnoglossus inconspectus SMIGIELSKA 1973 – SMIGIELSKA 1973: pl. 5, fig. 10 syn. Arnoglossus sp. – STEURBAUT & JONET 1981: pl. 4, fig. 5 syn. Arnoglossus aff. laterna – RADWANSKA 1992: fig. 156, pl. 36, fig. 8-10 syn. Arnoglossus sp.1 – RADWANSKA 1992: fig. 157, pl. 36, fig. 11 Investigated otoliths: About 30 otoliths, figured specimens are: 3 otoliths (figs. 353-355), Badenian, Middle Miocene, Niskowa, southern Poland (ZPalUW/RaNi 430, 431, 432); 5 otoliths (figs. 356359), Burdigalian, Lower Miocene, Costa di Caparica near Lisbon, Portugal (coll. Schwarzhans). Ontogeny and variability: Like A. holleri, A. taureri too is a rather small species with compressed otoliths. But in this case even very small specimens of about 1.2 to 1.5 mm can be identified due to their characteristic outline. Variability too is moderate in this species, however, erosive effects need to be taken into account as well. Discussion: A. taureri is rather easily recognized by its pronounced rectangular outline. Characteristically, the posterior portion of the otolith is much higher than the anterior portion. This effect is caused by the very strong and sharp postdorsal and postventral angles. Distribution: A. taureri occurs parallelly to A. holleri in the Lower and Middle Miocene of the Paratethys (Poland and Austria) and the European Atlantic Basins (Portugal and possibly also western France). It is missing from the North Sea Basin. Arnoglossus kokeni (BASSOLI 1906) Figs. 360-364 syn. Solea kokeni BASSOLI 1906 – BASSOLI 1906: pl. 2, fig. 3 syn. Arnoglossus bauzai SANZ ECHEVERRIA 1950 – SANZ ECHEVERRIA 1950: pl. 55, fig. 1.3 syn. Arnoglossus bauzai – BAUZA-RULLAN 1964: pl. 4, fig. 4 syn. Arnoglossus laterna – ANFOSSI & MOSNA 1973: pl. 12, fig. 11-13 syn. Arnoglossus bauzai – NOLF & MARTINELL 1980: pl. 5, fig. 26-29 syn. Arnoglossus kokeni – NOLF & STEURBAUT 1983: pl. 7, fig. 24 Investigated otoliths: 10 otoliths; the holotype of A. kokeni (fig. 360), Tortonian, Upper Miocene, Montegibbio, Toscana, Italy (IPUM 16628); 9 otoliths (figs. 361-364), Lower Pliocene, Dar Bel Hamri, NW-Morocco (coll. Schwarzhans). Schwarzhans: Pleuronectiformes 173 342 341a 341c 343a 343c 341b 343b 344 345 346 349 347 350a 350c 348 352 351 350b 353a 355c 355a 354 355b 353b 357 358 356 359 Figs. 341-352: Arnoglossus holleri WEINFURTER 1952 – 15 × Figs. 353-359: Arnoglossus taureri (WEINFURTER 1952) – 15 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 174 360c 360a 360b 362 361c 361a 361b 363 364a 364b Figs. 360-364: Arnoglossus kokeni (BASSOLI 1906) – 15 × Ontogeny and variability: Specimens smaller than 1.5 mm are more roundish in outline than those up to 2.2 mm. Otherwise, the otoliths of this species seem to be rather constant, even as far as the outline is concerned. Discussion: This are typical compact otoliths with a regular rectangular outline. In many ways they are similar to the recent A. laterna. However, otoliths of A. kokeni are almost always more compressed and more thickset. (It is interesting to note that the recent A. laterna occurred simultaneously in the Lower Pliocene of the North Sea Basin.) However, separation of the two species may not be possible in all instances. In the Lower Pliocene of NW-Morocco a second Arnoglossus species occurs parallelly – A. quadratus – which is similar in outline and habitus, but more elongate and even more thickset. Distribution: Upper Miocene of Italy, Lower Pliocene of Morocco, southern France and Spain. Arnoglossus quadratus n.sp. Figs. 365-373 Name: quadratus (lat.) = rectangular, referring to the outline of the otolith. Holotype: Fig. 365, SMF P 9317. Type-locality: Right river banks of the Oued Beth, ca. 1 km south of Dar Bel Hamri, NW-Morocco. Age: Lumachelle at the base of the Sands of Dar Bel Hamri, Lower Pliocene. Paratypes: 11 otoliths (figs. 366-373), topo- and stratitypic, SMF P 9318. Diagnosis: Moderately elongate, very massive and thickset otoliths up to 2.5 mm, with a regular rectangular outline. Inner face flat in adults, convex in juveniles. Sulcus moderately wide and deep, inclined at an angle of about 5 to 10°. Description (of adults): Outline: Moderately elongate, massive and very thickset otoliths with a regularly rectangular outline. Dorsal and ventral rims nearly straight, flat and horizontal. Anterior and posterior tips vertically cut. All rims smooth. Inner face: Flat in the horizontal and slightly convex in the vertical direction, rather smooth. Sulcus rather wide, moderately deep and anteriorly inclined at an angle of 5 to 10°. Sulcus opening somewhat reduced. Ostium and cauda clearly separated, ostium considerably longer and wider than cauda. Dorsal and ventral depressions wide, moderately deep, with indistinct boundaries, more or less connected around the caudal tip. Schwarzhans: Pleuronectiformes 175 365c 366a 365a 365b 366b 367 368 370 369 372a 372b 371a 371a 373 371b Figs. 365-373: Arnoglossus quadratus n.sp. – 15 × Other views: Otolith rims rather thickset, smooth. Outer face convex, smooth. Ontogeny and Variability: A. quadratus shows a very pronounced allometric ontogenetic change. Otoliths smaller than 1.8 mm in length are more compressed, show a more regularly rounded, somewhat undulating outline, a much more convex inner face and a narrower sulcus. Few specimens are intermediate in size and morphology (figs. 367-369) proving that both morphotypes indeed represent ontogenetic stages of a single species and not two separate species which could also have been assumed. This fact once more exemplifies that specific identification based on juvenile or subadult otoliths alone can be quite misleading and that establishing of new fossil species should be avoided to be based on such forms. Intraspecific variability on the other hand is much less prominent within the two ontogenetic categories. The smaller otoliths, however, are more apt to slight variations in the expression of the outline. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Side dimorphism: Not apparent. Discussion: A, quadratus is quite similar to A. kokeni with which it occurs simultaneously in northern Morocco (but not elsewhere). It differs in being somewhat more elongate and considerably more thickset. Also the index ol:cl is lesser and in adults the ostium is more widened as compared to the cauda. A. laterna, which is similar too, has much more thin otoliths and a higher index ol:cl (just like A. kokeni). Arnoglossus capensis BOULANGER 1898 Fig. 340 ?syn. Arnoglossus entomorhynchus STAUCH 1967 (acc. to HENSLEY, 1986) Investigated otoliths: 1 otolith (left side) from Gough Island, Central South Atlantic, west of South Africa, BMNH 1957.9.4.1. 176 376a 375 376c 374a 376a 377a 378a 377b 378b Fig. 374: Arnoglossus rueppellii (COCCO 1844) – 15 × Figs. 375-376: Arnoglossus tapeinosoma (BLEEKER 1866) – 15 × Fig. 377: Arnoglossus waitei NORMAN 1926 – 15 × Fig. 378: Arnoglossus aspilos (BLEEKER 1851) – 15 × Discussion: A. capensis differs from the other European and African species at the genus in the more regularly rounded elongate shape, the distinctly convex inner face and the ostial opening of the very deep sulcus. With this pattern it stands somewhat apart from all the other species of the genus. In fact, the general appearance is more like the species of the closely related genus Caulopsetta, an endemic New Zealandian genus. Distribution: Coasts of South Africa. The specimen from which the otolith was extracted originates from the Gough Island, an isolated central South Atlantic Island located at considerable distance from the African continent. Discussion: A. rueppellii is the first of a series of species with strongly inclined sulci. Sulcus inclination is in the order of 20-25°. Within this group it is the only one from the East Atlantic/Mediterranean, all the others originating from the IndoPacific. A. rueppellii is remarkable for its very short cauda and the oblique, dorsally projecting posterior rim. Distribution: Western Mediterranean and Adriatic and East Atlantic, from the Strait of Gibraltar to southern Morocco, in rather deep water (200550 m). Arnoglossus tapeinosoma (BLEEKER 1866) Figs. 375-376 Arnoglossus rueppellii (COCCO 1844) Fig. 374 syn. Bascanius taedifer SCHIODTE 1868 Investigated otoliths: 3 otoliths (2 right side; 1 left side, fig. ) from off Sardinia, Mediterranean, ZMH Ot. 17.6.1994.1-3 (leg. ZMUC 853172-76). syn. Arnoglossus macrolophus ALCOCK 1889 Investigated otoliths: 3 otoliths (2 right side and 1 left side) from the Gulf of Oman, ZMH Ot. 17.5.1994.4-5 (leg. BMNH 1939.5.24.1718-20) and BMNH 1939.5.24.1718-20. Discussion: Similar to A. rueppellii in many aspects, including the oblique, dorsally projecting Schwarzhans: Pleuronectiformes 177 380c 379a 379c 380a 380b 379b 381a 381b 381c 382 Fig. 379: Arnoglossus lapierri (NOLF 1988) – 15 × Fig. 380: Arnoglossus prudhommae (STEURBAUT 1984) – 15 × Figs. 381-382: Pleuroenctiformes indet. (Paratypes of Arnoglossus lapierri) – 15 × posterior rim. However, otoliths of A. tapeinosoma are more compressed and show a distinctive middorsal concavity. Distribution: Indo-West-Pacific, from the Persian Gulf to the Malay Peninsula and Indonesia. Arnoglossus aspilos (BLEEKER 1851) Fig. 378 Investigated otoliths: 1 otolith ( right side) from Singapore, ZMH Ot. 17.5.1994.6 (leg. ZMH 19883). Discussion: Similar to A. waitei, but more compressed. Arnoglossus waitei NORMAN 1926 Fig. 377 Investigated otoliths: 1 otolith (right side) from the Arafura Sea, Indonesia, BMNH 79.5.14.59-60. Discussion: A. waitei shows a more regular rectangular outline than A. rueppellii or A. tapeinosoma and the sulcus is less steeply inclined (about 10°). More similar in this respect is A. aspilos, but these otoliths are more compressed. Distribution: Arafura Sea and east coast of Queensland. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Malay Peninsula and Indonesia. Arnoglossus lapierrei (NOLF 1988) Fig. 379 (381-382) syn. genus Bothidarum lapierrei NOLF 1988 – NOLF 1988: pl. 14, fig. 9 (non figs. 10-11). Investigated otoliths: NOLF’s holotype (fig. 379; IRSNB P 4522) and his 2 paratypes (figs. 381-382; IRSNB P 4523-4524) from the tuillerie de Gan near Pau, Aquitaine Basin, SW-France, Clays of Gan, Ypresian, Lower Eocene, IRSNB. 178 Discussion: A. prudhommae is very similar to A. lapierrei, but considerably more compressed. The strong inclination of the sulcus (25°) characterize both species as representatives of the genus Arnoglossus. Distribution: Lower Oligocene of the Aquitaine Basin, SW-France. Fig. 383: Arnoglossus extremus SCHWARZHANS 1980 – 25 × Discussion: A. lapierrei is one of the fossil species with a steeply inclined sulcus and it is the oldest record of the genus. Otoliths are moderately compressed, rather thickset, with a rectangular outline and a clear sulcus opening. Remarks: NOLF (1988) also placed two additional specimens in this species (as paratypes). A review of those specimens (see figs. 381-382) indicates that they represent quite a different species and may be genus altogether (possibly a plesiomorphic fossil genus of some Bothidae). These otoliths are more thin, with a very characteristic and quite different outline and dorsal and ventral depressions (the latter with a very special outline) are clearly disconnected behind the cauda. Nolf has informed me that more material from this location is being expected soon. Therefore, I have refrained from establishing a new species based on this little material. Anyway, only the unique holotype is at present regarded as a valid record of A. lapierrei. Distribution: Lower Eocene of SW-France. Arnoglossus prudhommae (STEURBAUT 1984) Fig. 380 syn. Monolene prudhommae STEURBAUT 1984 – STEURBAUT 1984: pl. 34, fig. 26-27. Investigated otoliths: 1 paratype from Moulin d’Yrieu, Aquitaine Basin, SW-France, Sands of Yrieu, Lower Oligocene, IRSNB P 4240. Variability: According to the figures of STEURBAUT (1984) the holotype is slightly larger and shows some faint crenulation of the dorsal rim. Arnoglossus extremus SCHWARZHANS 1980 Fig. 383 syn. Arnoglossus extremus SCHWARZHANS 1980 – SCHWARZHANS 1980: fig. 576 Investigated otoliths: The unique holotype from McCullough’s Bridge (GS 9508), Canterbury, New Zealand South Island, Kaiatan, Upper Eocene, NZGS. Discussion: A. extremus closely resembles the two Early Tertiary species of Europe – A. lapierrei and A. prudhommae. It is recognized by its slightly more elongate shape and an index ol:cl of about 1.0. Distribution: Upper Eocene of New Zealand. Arnoglossus longus SCHWARZHANS 1980 Figs. 384-394 syn. Arnoglossus longus SCHWARZHANS 1980 – SCHWARZHANS 1980: fig. 577-578 syn. Arnoglossus novus – GRENFELL 1984: fig. 107-108, 214-216 Investigated otoliths: 69 otoliths, the holotype (fig. 386) and 1 paratype (fig. 385) from Pukeuri (GS 9685), Otago, New Zealand South Island, Altonian, Lower Miocene; 1 paratype from Waiau river (GS 1228), Clifden, Southland, New Zealand South Island, Altonian, Lower Miocene; 1 paratype from Otekaike (GS 9517), Otago, New Zealand South Island, Waitakian, Upper Oligocene, all NZGS; 2 otoliths (fig. 384) from Sutherland, Otago and 1 otolith from Pukeuri, both Altonian, Lower Miocene, coll. Richardson; 57 otoliths (figs. 387-392) from the Pareora River, Otago, Waitakian, Upper Oligocene and 5 otoliths (figs. 393-394) from Chatton, Otago, Duntroonian, Middle Oligocene, coll. Maxwell. Schwarzhans: Pleuronectiformes 179 385 384a 386 384b 388a 388c 387 389 388b 393 390 391 392 394 Figs. 384-394: Arnoglossus longus SCHWARZHANS 1980 – figs. 384-385, 387-394 = 15 ×; fig. 386 = 25 × Ontogeny and variability: Small otoliths (>1.2 mm) may not always be distinguishable from those of A. novus, whereas in adult otoliths this is not at all problematical. A series of small otoliths collected from the Upper and Middle Oligocene, a time when only A. longus was present, show a more compressed and rounded outline with somewhat undulating rims (figs. 387394). Juveniles of A. novus seem to have a more regular, smooth outline. Large otoliths show a certain variation in otolith and sulcus proportions and details of the outline. Discussion: See entry to A. novus. Distribution: Middle Oligocene to Lower Miocene of New Zealand. Arnoglossus novus SCHWARZHANS 1980 Figs. 395-397 syn. Arnoglossus novus SCHWARZHANS 1980 – SCHWARZHANS 1980: fig. 579-580 Investigated otoliths: 11 otoliths, the holotype (fig. 395) and 4 paratypes (fig. 396) from Pukeuri (GS 9685), Otago, New Zealand South Island, Altonian, Lower Miocene; 1 paratype from Weka Creek (GS 9567), Canterbury, New Zealand South Island, Altonian, Lower Miocene; 4 paratypes from Masterton near Wellington, New Zealand North Island, Waiauan, Middle Miocene, all NZGS; 1 otolith (fig. 397) from Pukeuri, coll. Richardson. Ontogeny and variability: Small otoliths of less than 1.0 to 1.5 mm show a much more rounded outline and in fact are so generalized that they Piscium Catalogus, Part Otolithi piscium, Vol. 2 180 396 395 397a 397c 397b 399a 398a 398b 399b 398c Figs. 395-397: Arnoglossus novus SCHWARZHANS 1980 – figs. 395-396 = 25 ×; fig. 397 = 15 × Figs. 398-399: Arnoglossus grenfelli n.sp. – 15 × can not be reliably distinguished from the parallelly occurring A. longus. Adult otoliths do not show much variability at all, except for some variations of the sulcus proportions. Discussion: A rather compressed, massive otolith with a rectangular outline and very deep sulcus and dorsal and ventral depressions. The inclination of the sulcus is steep, about 25°. From the parallelly occurring A. longus it is easily distinguished by its more compressed shape, the steeply inclined sulcus and the deep morphology of the inner face. Distribution: Lower and Middle Miocene of New Zealand. Arnoglossus grenfelli n.sp. Figs. 398-399 Name: In honor of H. Grenfell (Auckland) and his fine work on fossil otoliths from the North Island of New Zealand. Holotype: Fig. 398, BSP 1984 X 114. Type-locality: Martinborough, New Zealand North Island. Age: Wanganuian, Lower Pliocene. Paratypes: 1 otolith (fig. 399), topo- and stratitypic, BSP 1984 X 115. Diagnosis: Moderately elongate and massive otoliths with rectangular outline. Anteriorly with incipient rostrum. Otolith rims slightly undulating. Inclination of sulcus moderate (10°). Schwarzhans: Pleuronectiformes 181 c b a Fig. 400: Arnoglossus debilis (GILBERT 1905) – 15 × Description: Outline: Moderately elongate and massive otoliths with a typical rectangular outline. Dorsal rim straight, horizontal, with prominent pre-and postdorsal angles, the latter being more pronounced. Ventral rim flat, slightly curving. Posterior rim vertically cut to slightly oblique, then dorsally projecting. Anterior tip oblique, with incipient rostrum. All rims slightly undulating. Inner face: Slightly to moderately convex, with a narrow, moderately deep, slightly inclined sulcus (10°). Sulcus opening ostial to very slightly reduced. Ostium and cauda clearly separated, ostium longer, but not much wider than cauda. Dorsal and ventral depressions wide, moderately deep, connected around the caudal tip. Other views: Otolith rims moderately thickset, slightly undulating. Outer face slightly to moderately convex, rather smooth. Discussion: The otoliths of A. debilis are quite inconspicuous morphologically. They show a compressed, rounded rectangular shape and a not very steeply inclined sulcus (10°). The inner face is relatively flat and the otolith rather thin. In these aspects A. debilis resembles closest A. dalgleishi. Side dimorphism: An incipient side dimorphism seems to be present in this species. The left hand otolith shows a more convex inner face than the right hand otolith. Variability: The otoliths of this species seem to be quite constant morphologically. Discussion: A. grenfelli resembles the European A. laterna, but is more thickset and shows a smaller index ol:cl. Other Arnoglossus species of the region, fossil or recent, do not much resemble A. grenfelli. Arnoglossus debilis (GILBERT 1905) Fig. 400 Distribution: Hawaiian Islands, in rather deep water. Arnoglossus dalgleishi (VON BONDE 1922) Figs. 401-402 Investigated otoliths: 4 otoliths (3 right side and 1 left side) from off Zanzibar, ZMH Ot. 17.5.1994.79 (leg. BMNH 1939.5.24.1731-34) and BMNH 1939.5.24.1731-34. Discussion: A. dalgleishi resembles A. debilis in the rather thin appearance, the flat inner face and the low inclination angle of the sulcus. These two species probably form the core of still another cluster of Arnoglossus species to which NORMAN (1934) has assigned the name Anticitharus in subgeneric ranking. A. dalgleishi differs from A. debilis in the more rounded and conspicuously undulated otolith rims and in the reduction of the anterior part of the ostial colliculum. Distribution: South and East Africa. Investigated otoliths: 1 otolith (right side) from Hawaii, BMNH 1931.8.19.3. Piscium Catalogus, Part Otolithi piscium, Vol. 2 182 402a 401 402b Figs. 401-402: Arnoglossus dalgleishi (VON BONDE 1922) – 15 × Caulopsetta GILL 1893 Type-species: Pleuronectes scapha SCHNEIDER 1801 Diagnosis: Moderately thick and relatively large otoliths with a rounded rectangular outline; ventral rim shallow, gently curved, dorsal rim shallow too, with rounded pre-and postdorsal angles, posterior tip blunt, nearly vertically cut, sometimes with deep notch, anterior rim blunt, with incipient short rostrum, but without excisura; index l:h 1.4 to 1.6. Otolith size up to 6 mm. Ostium much longer than cauda and slightly wider too. Sulcus narrow, moderately deep, very slightly inclined, with a slightly reduced ostial opening. Cauda terminating relatively close to posterior tip of otolith. Separation of colliculi variable. Dorsal and ventral depressions deep, sharp and well marked, not completely connected around caudal tip to form a circumsulcal depression. Inner face moderately convex, not smooth; outer face flat to slightly convex, usually smooth. Rims sharp, sometimes slightly undulating. Measurements: l:h h:t ol:cl oh:ch s.i.a. con.i scapha 1.40-1.60 2.7 1.45-1.65 1.1-1.4 5° 5.5 +arnoglossoides 1.15-1.30 3.0 1.7-1.9 1.0-1.3 5-10° 3.0 Side dimorphism: The recent C. scapha exhibits some obvious side dimorphism in the morphology of the posterior rim of the otolith. In left hand specimens it is blunt, vertically cut. In right hand specimens the posterior rim is distinctly concave, sometimes deeply incised, with the postdorsal part being expanded and the postventral part projecting backwards. In the fossil C. arnoglossoides side dimorphism is similarly developed, but less pronounced. Ontogeny: Smaller specimens tend to be more compressed than adult ones, sometimes also being crenulated along the rims. Discussion: Caulopsetta no doubt is closely related to Arnoglossus. In fact, NORMAN (1934) did place Caulopsetta in the synonymy of the latter. Otoliths, however, differ in certain aspects from “typical” Arnoglossus species, thus warranting in my opinion the separation of the genus. Caulopsetta otoliths are larger, show a more regularly elongate outline, a low inclination angle of the sulcus and an incomplete connection of the dorsal and ventral depressions around the cauda. In a way this otolith pattern could be interpreted as plesiomorphic in comparison to the one found in Arnoglossus. Within Arnoglossus there is one species that stands somewhat apart from the rest Schwarzhans: Pleuronectiformes 183 403a 404 403c 403b 406 405 Figs. 403-406: Caulopsetta scapha (BLOCH & SCHNEIDER 1801) – 10 × and resembles Caulopsetta most – A. capensis (see also respective entry). May be this indicates that the dividing line between Arnoglossus and Caulopsetta needs to be revised somewhat. Species and distribution: Two recent species endemic to New Zealand – C. scapha and C. boops– and one fossil species from the Lower Miocene of New Zealand – C. arnoglossoides. Caulopsetta scapha Figs. 403-406 syn. Pseudorhombus hectoris GÜNTHER 1887 Investigated otoliths: 6 otoliths, 4 otoliths (2 right side and 2 left side, figs. 403-404) from off Christchurch, New Zealand, ZMH Ot. 23.5.1994.13 (leg. BMNH 1930.12.30.1-3) and BMNH 1930.12.30.1-3, 2 otoliths from the paratypes of C. hectoris (right side, figs. 405-406), Challenger stat. 167, BMNH 90.2.26.155-6. Side dimorphism: See entry to genus. Discussion: The two otoliths from the paratypes of C. hectoris perfectly fit with the other specimens of C. scapha supporting NORMAN’s synonymisation of the two species. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Endemic to the coasts of New Zealand. Caulopsetta arnoglossoides n.sp. Figs. 407-411 Name: Referring to the similarity of these otoliths (particularly the juvenile ones) to the genus Arnoglossus. Holotype: Fig. 410, NZGS. Type-locality: Ardgowan Shell Bed, Black Bridge, Otago, New Zealand South Island. Age: Altonian, Lower Miocene. Paratypes: 1 otolith (fig. 411), topo- and stratitypic; 3 otoliths (figs. 407-409) from Sutherlands Cliffs, Lower Tengawai River, Canterbury, New Zealand South Island; 2 otoliths from Clifden, Waiau River, Southland, Altonian; 1 otolith from Clelland road bridge, Tengawai River, Canterbury, Otaian, Lower Miocene; all NZGS. Diagnosis: Compressed, relatively thin otoliths with deeply curved ventral and flat dorsal rim. Posterior rim vertically cut or concave. Sulcus slightly inclined, deep and long. Dorsal and ventral depressions deep, well marked, incompletely connected around caudal tip. 184 409 408 407c 407a 407b 410a 410c 411 410b Figs. 407-411: Caulopsetta arnoglossoides n.sp. – 15 × Description (of adults): Outline: Compressed, rather thin otoliths, with deeply curved ventral rim and rather flat, horizontal dorsal rim, with rounded pre- and pronounced postdorsal angles. Posterior tip concave (in right hand otoliths) or vertically cut. Anterior tip blunt, but somewhat pointed. All rims smooth. Inner face: Moderately convex, not smooth. Sulcus narrow, long, terminating close to the posterior tip of the otolith, slightly inclined, deep. Sulcus opening very slightly reduced. Ostium and cauda separated, ostium considerably longer than cauda, but only slightly wider. Dorsal and ventral depressions deep, sharp, well marked, incompletely connected around caudal tip. Other views: Otolith rims sharp, smooth. Outer face flat to slightly convex, practically smooth. Ontogeny: Most specimens are of relatively small size and represent juvenile to subadult stages except for the holotype and two paratypes which are fully mature morphologically. The smaller specimens (less than 2 mm) are more compressed due to a more bluntly developed anterior tip and also the sulcus sometimes is more steeply inclined. The very smallest specimen of about 1.2 mm (fig. 409) shows some marginal crenulation. Side dimorphism: Like in the recent species, otoliths of the right side exhibit a concave posterior rim in adults, whereas in those of the left side it is vertically cut. Discussion: This is a “typical” species of the genus Caulopsetta, differing from the recent C. scapha in being more compressed and showing a more deeply curved ventral rim. Juveniles, however, bear some resemblance to Arnoglossus otoliths in outline due to the more bluntly developed anterior tip. Two parallelly occurring species of Arnoglossus – A. longus and A. novus – are much more thickset with a rectangular outline of the otolith. A. longus is also more elongate. Even juveniles of C. arnoglossoides can reliably been differentiated from these two species. Schwarzhans: Pleuronectiformes 185 413a 413c 412 413b 414-A 414-B Figs. 412-414-A, 414-B: Lophonectes gallus GÜNTHER 1880 – 15 × Lophonectes GÜNTHER 1880 Type-species: Lophonectes gallus Measurements: gallus syn. Lophorhombus MACLEAY 1883 (type-species: Lophorhombus cristatus, syn. L. gallus) Diagnosis: Relatively thickset otoliths with an elongated, rounded outline; ventral rim shallow, gently curved, dorsal rim also regularly curved, with a faint and strongly rounded predorsal angle, posterior tip rounded, anterior rim rounded, with incipient short rostrum, but without excisura; index l:h 1.55-1.65. Otolith size slightly over 3 mm. Ostium longer than cauda and slightly wider too. Sulcus rather deep, very slightly inclined, with a slightly reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions moderately deep and well marked, more or less connected around caudal tip to form a circumsulcal depression. Inner face moderately convex, not very smooth; outer face flat, rather smooth. Rims moderately sharp, smooth. Piscium Catalogus, Part Otolithi piscium, Vol. 2 l:h 1.55-1.65 h:t 2.5 ol:cl 1.2-1.8 oh:ch 1.2-1.5 s.i.a. 5° con.i 3.2 Side dimorphism: Not apparent. Variability: Variability within this species is moderate, restricted to variations of the proportions of the sulcus, expression of the predorsal angle and thickness of the rims. Discussion: The elongate otoliths of Lophonectes with their regularly rounded outline and the rather deep sulcus which is only slightly inclined definitely resembles otoliths of the genus Caulopsetta and of the species Arnoglossus capensis. Species and distribution: Lophonectes is a monospecific genus with a single species – L. gallus – from SE-Australia, Tasmania and New Zealand. Lophonectes gallus GÜNTHER 1880 Fig. 412-414-A, 414-B syn. Lophorhombus cristatus MACLEAY 1883 syn. Arnoglossus mongonuiensis REGAN 1914 186 415 416a 416c 416b Figs. 415-416: Psettina iijimae (JORDAN & STARKS 1904) – 15 × Investigated otoliths: 5 otoliths (4 right side and 1 left side) from Port Jackson, New South Wales, Australia, ZMH Ot. 25.5.1994.2-5 (leg. BMNH 90.9.23.46-51) and BMNH 90.9.23.46-51. Inner face slightly to moderately convex, not very smooth; outer face slightly convex, smooth. Rims thickset, smooth to slightly undulating. Measurements: Discussion and distribution: See entry to genus (monospecific genus). Psettina HUBBS 1915 Type-species: Engyprosopon iijimae JORDAN & STARKS 1904 syn. Crossolepis NORMAN 1927 (type-species: Arnoglossus brevirictis) syn. Crossobothus FOWLER 1934 (type-species: Bothus (Crossobothus) variegatus) syn. Psettinella FEDOROV & FOROSHCHUK 1988 (type-species: N.N.) Diagnosis: Relatively thick, massive, small otoliths with a rounded outline; ventral rim shallow, regularly curved, dorsal rim curved or flat, then with rounded pre-and postdorsal angles, posterior tip blunt, rounded, anterior rim blunt, sometimes with incipient short rostrum, but without excisura; index l:h 1.1-1.4. Otolith size up to 3 mm. Ostium longer than cauda and considerably wider. Sulcus wide, moderately deep, slightly inclined, with a slightly reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions moderately deep and well marked, connected around caudal tip to form a circumsulcal depression. iijimae brevirictis l:h 1.15-1.25 1.40 h:t 2.2 2.4 ol:cl 1.3-1.5 1.4 oh:ch 1.3-1.5 1.4 s.i.a. 5° 5° con.i 2.8 3.7 Side dimorphism: Otoliths of the left side seem to be more rounded in outline, which is particularly relevant for the expression of the dorsal rim. Also the colliculi are less well separated. Discussion: Psettina is very close to Arnoglossus (in accordance with NORMAN, 1934). In fact, differentiation of the two genera based on otoliths alone may not always be possible. Psettina otoliths are characterized by their roundish shape and the rather wide ostium. Species and distribution: At least 6 species from the Indo-West-Pacific, usually in rather deep water. Two species are known from India to the Indo-Australian Archipelago – P. brevirictis and P. profunda – and three species from Japan – P. iijimae, P. gigantea, P. tosana and P. variegata. Otoliths are known from P. brevirictis and P. iijimae. Psettina brevirictis (ALCOCK 1890) Fig. 417 Investigated otoliths: 1 otolith (right side) from the Madras coast, India, BMNH 1927.1.6.30-32. Schwarzhans: Pleuronectiformes 187 Discussion: Otoliths of P. iijimae are considerably more compressed. Distribution: SE-India and Indonesia. Psettina iijimae (JORDAN & STARKS 1904) Figs. 415-416 Investigated otoliths: 2 otoliths (right and left side) from Okishima, Japan, ZMH Ot. 25.5.1994.1 (leg. BMNH 1931.8.19.4) and BMNH 1931.8.19.4. Discussion: More compressed than P. brevirictis. Distribution: Southern Japan. Taeniopsetta GILBERT 1905 Type-species: Taeniopsetta radula GILBERT 1905 Diagnosis: Moderately thick and rather large otoliths with a more or less rectangular outline; ventral rim shallow, postventrally pronounced, dorsal rim flat, horizontal, with marked pre-and postdorsal angles, posterior tip blunt, oblique, its tip shifted ventrally, anterior rim blunt, rarely with incipient short rostrum, but without excisura; index l:h 1.3-1.4. Otolith size up to 3.5-4 mm. Ostium longer than cauda and very slightly wider. Sulcus very narrow, moderately deep, slightly inclined, with somewhat reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions moderately deep, wide and well marked, connected around caudal tip to form a circumsulcal depression. Inner face rather flat and rather smooth; outer face convex, smooth to slightly ornamented. Rims moderately sharp, usually somewhat undulating. Measurements: ocellata radula †dorsolobata l:h 1.30-1.40 1.40 1.30-1.45 h:t 2.5 2.2 nm ol:cl 1.5-1.6 1.45 1.0-1.1 oh:ch 1.1-1.2 1.25 1.3-1.4 s.i.a. 5° 0° 0° con.i 4 4.5 nm Side dimorphism: Not apparent. Variability: Variability of otoliths in this genus is very much restricted to details of the expression of the dorsal rim. Piscium Catalogus, Part Otolithi piscium, Vol. 2 a c b Fig. 417: Psettina brevirictis (ALCOCK 1890) – 15 × Discussion: NORMAN (1934) placed Taeniopsetta in his Paralichthyinae, in a systematic position quite distant to the genera here included in the Arnoglossus-Group. Its otoliths, however, show considerable resemblance to those of the other genera in this group, particularly as far as outline and inclination of the sulcus is concerned. I have therefore tentatively included Taeniopsetta in the Arnoglossus-Group. Species and distribution: Two recent species with rather restricted distribution patterns – T. ocellata from the Indian Ocean and T. radula from Hawaii. In addition I have tentatively placed in this genus the fossil T. dorsolobata from the Lower Miocene of New Zealand. Taeniopsetta ocellata (GÜNTHER 1880) Figs. 418-421 Investigated otoliths: 4 otoliths (3 right side and 1 left side) from Saya de Molha Bank, Indian Ocean, ZMH Ot. 25.5.1994.6-8 (leg. BMNH 1908.3.23.123-5) and BMNH 1908.3.23.123-5. Variability: The expression of the predorsal angle seems to be the only character of a certain variance. Discussion: See entry to T. dorsolobata and to T. radula. Distribution: NORMAN (1934) reported this species from two very distant locations. One location is the Admirality Islands near New Guinea (holotype), the other the Saya de Molha Bank north of Mauritius in the Indian Ocean (investigated specimens). 188 419 418c 418a 418b 421 420 422c 422b 422a Figs. 418-421: Taeniopsetta ocellata (GÜNTHER 1880) – 10 × Fig. 422: Taeniopsetta radula GILBERT 1905 – 15 × Investigated otoliths: 1 otolith (right side), paratype, from Hawaii, BMNH 1931.8.19.1-2. from Pukeuri, Otago, New Zealand South Island, Altonian, Lower Miocene, NZGS, and 1 otolith (fig. 426) from Awamoa Creek, Otago, New Zealand South Island, Altonian, Lower Miocene, coll. Richardson. Discussion: The otolith of T. radula is slightly more thickset than those of T. ocellata, its sulcus somewhat wider and the postdorsal angle is more strongly developed than the predorsal angle. Ontogeny and variability: The smallest specimen (fig. 425) is more elongate than the larger ones. One specimen (fig. 424) shows a slightly stronger rostrum. Distribution: Restricted to the Hawaiian Islands. Discussion: T. dorsolobata is placed provisionally in this genus. It differs from the two recent species in a number of aspects. These are the index ol:cl, the somewhat wider sulcus, the incipient rostrum, the strongly pronounced medio- to postdorsal angle (in T. ocellata it is the predorsal angle, in T. radula it is the postdorsal angle) and the rather flat inner face. However, there is no other recent genus, which would show similar features, but it may eventually turn out that T. dorsolobata represents an extinct genus altogether. Taeniopsetta radula GILBERT 1905 Fig. 422 Taeniopsetta dorsolobata (SCHWARZHANS 1980) Figs. 423-426 syn. Bothidarum dorsolobatus SCHWARZHANS 1980 – SCHWARZHANS 1980: fig. 582-584 Investigated otoliths: 4 otoliths, the holotype (fig. 423) and the two paratypes (figs. 424-425) Schwarzhans: Pleuronectiformes 189 425 424 423 426a 426b 426c Figs. 423-426: Taeniopsetta dorsolobata (SCHWARZHANS 1980) – 25 × Distribution: Lower Miocene of the southeastern part of the South Island of New Zealand. 7.6.7 Monolene-Laeops Group Genera: In this group I have tentatively placed 6 genera – Trichopsetta, Engyophrys, Perissias, Laeops, Japanolaeops and Monolene. The first three genera are confined to the tropical coasts of America, Monolene occurs along the coasts of America and West Africa, and Laeops and Japanolaeops are distributed in the Indo-Pacific. Otoliths are unknown from Perissias and Japanolaeops. Perissias is placed here, because of NORMAN’s correlation with Trichopsetta and Engyophrys, Japanolaeops because of its apparent relationship to Laeops. There are also few fossil records – one possible species of Monolene from the Upper Oligocene of the North Sea Basin and two species of Laeops, one from the Middle Miocene of the Paratethys and one from the Lower Pliocene of Morocco. Definition and relationship: Otoliths of the Monolene-Laeops Group closely resemble those of the Arnoglossus Group. They are compact and small and compressed in outline. The sulcus opening is not much reduced. Dorsal and ventral depressions are well marked and connected around the caudal tip. The inner face is rather flat, sometimes almost completely flat. Differing from the Arnoglossus Group is the more trapezoidal than rectangular outline of the otoliths and in many (but not all) instances the almost horizon- Piscium Catalogus, Part Otolithi piscium, Vol. 2 tal orientation of the sulcus. The inner face is usually “more” flat and some genera show a pronounced side dimorphism. However, there exist a number of intermediate morphologies, which in several instances does not allow to draw a very definite boundary between the members of the two groups. In NORMAN’s (1934) concept most of the genera placed in the Monolene-Laeops Group where not regarded to be particularly related to the genera of the Arnoglossus Group. In fact, he placed all genera in his Paralichthyinae except for Laeops (and Japanolaeops, which was described later). NORMAN used three characters to differentiate among the two subfamilies Paralichthynae and Bothinae – placement of the ventral fin in relation to each other, location of the cleithra in relation to the most anterior of the ventral fins and presence or absence of the processus transversus on the caudal vertebrae. The implications of these three characters for the distinction of the two genera Monolene and Laeops has been discussed at length by NIELSEN (1961) in his description of Monolene mertensi, a species originally described as belonging to Laeops. Interestingly, the fishes of these two genera not only resemble each other in habitus but also there otoliths can hardly be differentiated. It may be possible that the latter is due the “very reduced” morphology of the otoliths which leaves few diagnostically valid characters. On the other hand, such tendencies or otolith patterns are not observed in any of the other Paralichthynae genera (Paralichthys, Pseudorhombus, Syacium and Citharichthys Groups). The only exceptions from this are the two genera Trichopsetta and 190 Engyophrys. – These are the principal reasons, why I have united the 6 genera listed above in the Monolene-Laeops Group and placed them in the vicinity of the Arnoglossus Group, well aware, of course, that this classification contradicts the ichthyological concept of NORMAN. In recent literature, however, (HENSLEY & AHLSTROM, 1984, NELSON, 1994) these genera in question are included with the Bothidae, very similar indeed to the otolith grouping as proposed here. Trichopsetta GILL 1889 Type-species: Citharichthys ventralis GOODE & BEAN 1886 Diagnosis: Relatively thick, small otoliths with a more or less trapezoidal outline; ventral rim shallow, almost straight, dorsal rim flat, with marked pre-and postdorsal angles, posterior tip blunt, slightly oblique and ventrally pronounced, anterior rim oblique, with incipient short rostrum, but without excisura; index l:h 1.45-1.55. Otolith size about 3 mm. Ostium longer than cauda and slightly wider too. Sulcus moderately deep, slightly inclined, with a somewhat reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions wide, well marked towards the sulcus, more or less connected around caudal tip to form a circumsulcal depression. Inner face almost flat except for the somewhat elevated area around the sulcus, rather smooth; outer face convex, smooth. Rims moderately sharp, smooth. Measurements: l:h ventralis (right) 1.45 ventralis (left) 1.55 melasma (right) 1.60 h:t 2.3 nm 2.9 ol:cl 1.2 2.2 1.3 oh:ch 1.0 1.3 1.0 s.i.a. con.o 10° 2.7 0° nm 10° 5 Side dimorphism: Trichopsetta belongs to the genera within this group with a rather pronounced side dimorphism. This is most obvious in the outline of the otolith – the right hand otolith shows the typical trapezoidal outline, whereas the left hand otolith is much more rounded. Also the right hand otolith shows an inclined sulcus, the left hand otolith a nearly horizontal orientation. Separation of colliculi is much less developed in the left hand otolith, the sulcus more narrow and the index ol:cl is much larger. Discussion: Trichopsetta apparently is closely related to Engyophrys. With otoliths of more species of the two genera becoming available I would expect differentiation of the two genera to become very difficult, if at all possible. In fact, the separation of the two genera appears to be somewhat artificial judging from otoliths alone. Species and distribution: Trichopsetta includes 4 recent species – T. caribbaea, T. melasma, T. orbisculus and T. ventralis – all endemic to the deeper water of the Gulf of Mexico and the Caribbean. Trichopsetta ventralis (GOODE & BEAN 1886) Figs. 427-428, 16 Investigated otoliths: 2 otoliths (right and left side) from off Florida (29°14’N/88°09’W), BMNH 96.2.10.74. Discussion: Otoliths of T. ventralis are more compressed than those of T. melasma. Distribution: In deeper water throughout the Gulf of Mexico. Trichopsetta melasma ANDERSON & GUTHERZ 1967 Fig. 429 Investigated otoliths: 1 otolith (right side), paratype, Andros Isl., 24°34’N/79°6’W, BMNH 1966.6.13.3. Discussion: More elongate than T. ventralis and with pointed posterior tip. In appearance T. melasma is very similar to Engyophrys sanctilaurenti (see respective entry). The separation of the two genera, at least by means of otoliths, seems rather artificial Engyophrys JORDAN & BOLLMAN 1890 Type-species: Engyophrys sanctilaurenti JORDAN & BOLLMAN 1890 Diagnosis: Relatively thick, small otoliths with a rounded trapezoidal outline; ventral rim shallow, almost straight, dorsal rim flat, with rounded pre-and postdorsal angles, posterior tip venSchwarzhans: Pleuronectiformes 191 428 427 427a 427b 429a 429b Figs. 427-428: Trichopsetta ventralis (GOODE & BEAN 1886) – 15 × Fig. 429: Trichopsetta melasma ANDERSON & GUTHERZ 1967 – 15 × trally pointed in right hand otoliths, rounded in left hand otoliths, anterior rim blunt, without rostrum; index l:h about 1.55. Otolith size about 3 mm. Ostium longer than cauda and slightly wider too. Sulcus moderately deep, horizontal, with a somewhat reduced ostial opening. Cauda terminating at some distance from posterior tip of otolith. Colliculi indistinctly separated. Dorsal and ventral depressions wide, not well marked, more or less connected around caudal tip to form a circumsulcal depression. Inner face almost flat, rather smooth; outer face convex, smooth. Rims moderately sharp, smooth. Discussion: Engyophrys apparently is loosely related to Trichopsetta. Main difference is the development of the posterior tip of the otolith and the lack of a sulcus inclination. Species and distribution: Three species, one from the Pacific coast of Panama and Columbia – E. sanctilaurenti – and one from the Atlantic coast off Florida – E. sentus (acc. to NORMAN only known from the single holotype) – and one from Brazil – E. ciliaris. Engyophrys sanctilaurenti JORDAN & BOLLMAN 1890 Figs. 430-431 Measurements: sanctilaurenti l:h 1.55 h:t 2.4 ol:cl 1.6-1.7 oh:ch 1.3 s.i.a. 0° con.o 3 Side dimorphism: Side dimorphism in Engyophrys is somewhat less developed than in Trichopsetta. The right hand otolith shows a pointed posterior tip, the left hand otolith a rounded posterior tip. Also the sulcus is narrower and deeper in left hand otoliths. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 2 otoliths (right and left side) from the Pacific coast of Mexico, off Mazatlan (23°6’N/107°9’W), ZMH Ot. 26.5.1994.1-2 (leg. ZMUC ex SIO 59-262-64A). Discussion and distribution: See entry to genus. 192 430c 430a 431 430b Figs. 430-431: Engyophrys sanctilaurenti JORDAN & BOLLMAN 1890 – 15 × Perissias JORDAN & EVERMANN 1898 Type-species: Platophrys taeniopterus GILBERT 1890 Remarks: A specimen of P. taeniopterus in the ZMUC collection was x-rayed and revealed that otoliths have been dissolved (by formalin). According to NORMAN (1934) Perissias is closely related to Trichopsetta and Engyophrys. Species and distribution: Perissias is a monospecific genus with P. taeniopterus known from the Pacific coast of California to Panama. Laeops GÜNTHER 1880 Type-species: Laeops parviceps GÜNTHER 1880 syn. Scianectes ALCOCK 1889 (type-species: Scianectes macrophthalmus) syn. Lambdopsetta SMITH & POPE 1906 (typespecies: Lambdopsetta kitaharae) syn. Laeoptichthys HUBBS 1915 (type-species: Laeoptichthys fragilis, ?syn. L. kitaharae) syn. Leptolaeops FOWLER 1934 (type-species: Leptolaeops clarus) Diagnosis: Relatively thick, small and compressed otoliths with a more or less trapezoidal outline; ventral rim shallow, almost straight, dorsal rim flat, with marked pre-and postdorsal angles, posterior tip blunt, slightly oblique and ventrally pronounced, anterior rim oblique, with incipient short rostrum, but without excisura; index l:h 1.10-1.40. Otolith size up to 3 mm. Ostium longer than cauda and usually wider. Sulcus moderately deep, sometimes inclined, with a somewhat reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions wide, well marked towards the sulcus, connected around caudal tip to form a circumsulcal depression. Inner face almost flat except for the somewhat elevated area around the sulcus, rather smooth; outer face convex, smooth. Rims moderately sharp to thickset, smooth. Measurements: guentheri nigrescens macrophthalmus nigromaculatus †splendens †rharbensis l:h h:t 1.35-1.40 2.6 1.20-1.30 2.8 1.15-1.20 2.8 1.10 nm 1.20 3.0 1.00-1.10 3.0-3.3 ol:cl oh:ch s.i.a. con.o 1.6-1.8 1.6 0° 3.5 1.3-1.5 1.2-1.3 5-10° 2.5 1.1-1.4 1.5 5-10° 2.7 2.0 1.1 0° nm 1.3-1.4 1.2 10-15° 3.0 1.9-2.2 1.6-1.7 10° 3.0 Side dimorphism: Generally not apparent. In the fossil L. splendens the right hand otolith is more rounded in outline and lacks a rostrum. However, since this is an extremely small otolith these apparent differences could at least partially be due to allometric ontogenetic growth. Ontogeny and variability: Except for the possible case in the fossil L. splendens no remarkable ontogenetic changes have been observed. Otoliths of about 1.5 mm usually have developed all pertinent diagnostic features. Variability too in most species seems to be moderate, mainly restricted to details of the outline. Discussion: Otoliths of Laeops are extremely similar to those of the genus Monolene, which in ichthyological literature are not regarded as particSchwarzhans: Pleuronectiformes 193 433 432c 432b 432a Figs. 432-433: Laeops guentheri ALCOCK 1890 – 15 × ularly related (see NORMAN 1934 and general remarks to the Monolene-Laeops Group). In fact I can not find a single otolith character that would allow a safe distinction of the two. Both genera are quite specious and so far only a limited number of species are known from otoliths. Once our knowledge increases I would expect even more uncertainty in telling the species of the two genera apart by means of otoliths. This implies, of course, that the allocation of fossil otoliths to the one or other genus probably will always remain somewhat questionable (see entries to the fossil species). In rare instances even the distinction to certain species of the genus Arnoglossus may become problematical. The single most reliable character to distinguish otoliths of Monolene and Laeops from those genera of the Arnoglossus Group probably is the trapezoidal outline of the former. Species and distribution: There are about 15 nominally valid species in the genus Laeops: L. clarus, L. cypho and L. gracilis (all described by FOWLER, 1933 from the Philippines), L. guentheri, L. kitaharae, L. lanceolata, L. variegata (the two latter likely synonyms of L. kitaharae), L. macrophthalmus, L. natalensis, L. nigrescens, L. nigromaculatus, L. parviceps, L. pectoralis, L. sinusarabici, L. tungkongensis. Judging from the comments and listings of NORMAN (1934) and CHABANAUD (1939) the genus is in need of revision and may be less than 10 species may finally prove to be valid. Otoliths of four recent species are figured here. Otoliths of a fifth species – L. pectoralis – are figured in SMALE et al. (1995). They resemble those of L. guentheri with the predorsal lobe. Laeops is widely distributed in the Indo-WestPacific, from South Africa to Japan and the Philippines. In addition there are two fossil records tentatively placed in this genus (regarding Monolene as an alternative allocation) – L. splendens from the Middle Miocene of the Paratethys (AusPiscium Catalogus, Part Otolithi piscium, Vol. 2 tria) and L. rharbensis from the Lower Pliocene of NW-Morocco. Laeops guentheri ALCOCK 1890 Figs. 432-433 Investigated otoliths: 3 otoliths (2 right side and 1 left side) from off Calcutta, India, ZMH Ot. 26.5.1994.3-4 (leg. BMNH 1928.3.29.3-4) and BMNH 1928.3.29.3-4. Discussion: The otoliths of L. guentheri are characterized by their rather elongate shape, the lack of a sulcal inclination and a conspicuous middorsal concavity. Distribution: Persian Gulf and along the coasts of Pakistan and India to Burma. Laeops nigrescens LLOYD 1907 Figs. 434-437 Investigated otoliths: 14 otoliths (9 right side and 5 left side) from the Gulf of Aden, ZMH Ot. 26.5.1994.5-12 (leg. BMNH 1939.5.24.1739-73) and BMNH 1939.5.24.1739-73. Ontogeny and variability: Both ontogenetic changes and variability in this species is relatively small and restricted to minor variations in the outline of the otolith. Discussion: Otoliths of L. nigrescens are compact, compressed and show the typical trapezoidal outline. They are very similar to L. macrophthalmus. Distribution: Gulf of Aden, in relatively deep water. 194 435 434a 434c 434b 436 439 437 438a 438c 440 438b Figs. 434-437: Laeops nigrescens LLOYD 1907 – 15 × Figs. 438-439: Laeops macrophthalmus (ALCOCK 1889) – 15 × Fig. 440: Laeops nigromaculatus VON BONDE 1922 – 15 × Laeops macrophthalmus (ALCOCK 1889) Figs. 438-439 Distribution: From the Gulf of Oman through the Indian Ocean to Burma. syn. Scianectes lophoptera ALCOCK 1889 Investigated otoliths: 5 otoliths, 2 otoliths (right and left side, fig. 438-439) from the bay of Bengal, BMNH 1927.1.6.59-60, 3 otoliths (2 right side, 1 left side) from the Sea of Oman, ZMH Ot. 26.5.1994.13-15 (leg. BMNH 1904.5.25.2-5). Discussion: L. macrophthalmus is very similar to L. nigrescens. However, the otoliths seem to be just slightly more compressed and the predorsal angle more pronounced. Laeops nigromaculatus VON BONDE 1922 Fig. 440 Investigated otoliths: 1 slightly eroded otolith (right side), paratype, off Natal, South Africa, BMNH 1922.3.27.13-14. Discussion: A very compressed, roundish otolith with an anisole narrow sulcus, including a very narrow ostium. Schwarzhans: Pleuronectiformes 195 443a 441a 441c 443c 442 441b 443b Figs. 441-443: Laeops splendens (SCHUBERT 1906) – 15 × Distribution: Off Natal coast and Delagoa Bay, South Africa. distinguish these otoliths from those of the known recent species. In all other characters it perfectly fits into this genus. Laeops splendens (SCHUBERT 1906) Figs. 441-443 Distribution: Middle Miocene of the Vienna Basin (Paratethys). syn. Ot. Pleuronectidarum splendens SCHUBERT 1906 – SCHUBERT 1906: pl. 6, fig. 10-11 syn. Solea tenuis SCHUBERT 1906 – SCHUBERT 1906: pl. 6, fig. 9 syn. Hippoglossoides splendens – NOLF 1981: pl. 3, fig. 11 syn. genus Pleuronectiformorum tenuis – NOLF 1981: no fig. Investigated otoliths: 3 otoliths, the lectotype (GBW 1906/1/57a; fig. 441) and paralectotype (GBW 1906/1/57b; fig. 442) of Ot. Pleuronectidarum splendens from the Badenian, Middle Miocene of Bad Vöslau, Vienna Basin, Austria and the holotype (GBW 1906/1/56; fig. 443) of Solea tenuis from the Badenian of Neudorf an der Merch, Vienna Basin, Slowakia. Side dimorphism: The two types of Ot. Pleuronectidarum splendens are left hand otoliths, whereas the holotype of Solea tenuis is a very small right hand otolith. The latter differs in the more roundish shape and the complete lack of a rostrum. This may indicate some degree of side dimorphism, but at least part of the morphological difference may better be explained by allometric ontogenetic growth. Because of these uncertainties, this specimen was not used for measurements (see entry to genus). Discussion: The shape of the dorsal and posterior rims and the rather strongly inclined sulcus Piscium Catalogus, Part Otolithi piscium, Vol. 2 Laeops rharbensis n.sp. Figs. 444-447 Name: Referring to the Rharb province of NWMorocco, where these otoliths were found. Holotype: Fig. 444, SMF P 9319. Type-locality: Right river banks of the Oued Beth, ca. 1 km south of Dar Bel Hamri, NW-Morocco. Age: Lumachelle at the base of the Sands of Dar Bel Hamri, Lower Pliocene. Paratypes: 6 otoliths (figs. 445-447), topo- and stratitypic., SMF P 9320. Diagnosis: Very compressed otoliths with an index l:h of about 1.0. Outline trapezoidal, somewhat undulating. Inner face rather flat and smooth, with slightly inclined sulcus. Ostium much longer and wider than cauda. Description: Outline: Massive, compressed otoliths, about as long as high, with somewhat undulating trapezoidal outline. Ventral rim flat, dorsal rim almost straight, with pre- and postdorsal angles. Anterior and posterior rims oblique, anterior rim with incipient rostrum, posterior rim often with small notch. Inner face: Relatively flat and smooth, with inclined and rather short sulcus. Sulcus opening somewhat reduced. Ostium much longer and wider than cauda, the latter terminating at moderate distance from the posterior rim of the oto- 196 444c 444a 445a 444b 445b 447a 446b 446a 446c 447b Figs. 444-447: Laeops rharbensis n.sp. – 15 × lith. Colliculi well separated, caudal colliculum very small. Dorsal and ventral depressions wide, rather shallow, but well marked towards the sulcus, connected around the caudal tip. Other views: Otolith rim rather thickset, smooth. Outer face convex, smooth. Ontogeny and Variability: In smaller specimens the marginal crenulation is more strongly developed. Also otoliths seem to grow more thickset with size. Variability is minor, in principal restricted to details of the outline. Side dimorphism: Not apparent. Discussion: L. rharbensis is a typical example of a species that based on isolated otoliths could either be placed in the genus Laeops or Monolene. In Laeops it closely resembles L. nigrescens and L. macrophthalmus except for the somewhat more compressed outline and the very tiny cauda. In Monolene it resembles M. microstoma, Recent from the West African coast. This rather variable species has even more thickset otoliths, a deep sulcus and dorsal and ventral depressions and again a larger cauda. Of course, it is tempting to place the fossil species from Morocco in Monolene because a recent species is known from the same area at large, but the recent species (M. microstoma) somewhat departs from the “typical” otolith morphology to be found in the genus. In general, the trapezoidal outline seems to be more common in Laeops and this is the main reason, why I have placed L. rharbensis here. Japanolaeops AMAOKA 1969 Type-species: Japanolaeops dentatus AMAOKA 1969 Remarks: Otoliths of Japanolaeops have not been available for identification. Specimens kindly dissected by K. Sasaki were found to had their otoliths dissolved due to formalin. Japanolaeops was tentatively included in the Monolene-Laeops Group because of its apparent affinities to Laeops. Species and distribution: Japanolaeops is a monospecific genus with J. dentatus being endemic to Japan. Schwarzhans: Pleuronectiformes 197 Monolene GOODE 1881 Type-species: Monolene sessilicauda GOODE 1881 syn. Thyris GOODE 1881 (preoccupied; type-species: Thyris pellucidus, syn. M. sessilicauda) syn. Delothyris GOODE 1884 (substitute for Thyris) Diagnosis: Moderately thick to thick, small otoliths with an irregular roundish to rectangular to trapezoidal outline; ventral rim usually deeper than dorsal rim, the latter flat, often with marked pre-and postdorsal angles, posterior tip blunt, slightly oblique and dorsally pronounced or vertically cut, anterior rim blunt or rounded, without rostrum; index l:h 1.1-1.6. Otolith size rarely reaching 3 mm. Ostium longer than cauda and slightly wider too. Sulcus moderately deep to deep, sometimes slightly inclined, with a somewhat reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions wide, usually deep, well marked towards the sulcus, connected around caudal tip to form a circumsulcal depression. Inner face rather flat except for the somewhat elevated area around the sulcus, moderately smooth; outer face convex, smooth. Rims moderately sharp to thickset, smooth. Measurements: antillarum sessilicauda microstoma maculipinna †priscus l:h h:t 1.15-1.40 2.8 1.25 2.3 1.10-1.35 1.8 1.60 nm 1.20-1.30 2.5-3.0 ol:cl 1.4-1.7 1.4 1.5-2.0 1.6 1.2-1.4 oh:ch s.i.a. con.o 1.0-1.3 0-5° 4.5 1.1 5° 3.5 1.0-1.2 0-5° 1.5 1.2 0° nm 1.0-1.3 0° 3.8 Side dimorphism: Side dimorphism in the otoliths of this genus is not very obvious and may not occur in all species. Sometimes the sulcus of left hand specimens seems to be more deepened and they can also be more roundish in outline. Ontogeny and variability: Due to the rather reduced morphology of the otoliths, ontogenetic changes are strong. Even small otoliths of less than 2 mm in size generally seem to be morphologically mature. Variability on the other hand often is very considerable, in particular concerning the outline of the otoliths. This character can be become so variable in some species that specific identification can be seriously hampered. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Otoliths of Monolene very closely resemble those of Laeops (see respective entry) and sometimes it is difficult, if at all possible, to distinguish amongst the two by means of otoliths alone. Species and distribution: According to NIELSEN (1961) the genus Monolene contains 10 species, 3 from the Pacific coast of America (M. dubiosa, M. asaedae, M. maculipinna), 5 from the Atlantic coast of America (M. sessilicauda, M. antillarum, M. atrimana, M. danae, M. megalepis) and 2 from West Africa (M. microstoma, M. mertensi). In addition, I have tentatively placed a fossil record from the Upper Oligocene of Germany (North Sea Basin) in this genus (M. priscus). Monolene antillarum NORMAN 1933 Figs. 448-451 Investigated otoliths: 8 otoliths (6 right side and 2 left side) from off Dry Tortugas, Florida, ZMH Ot. 26.5.1994.16-21 (leg. BMNH 1933.10.12.137143) and BMNH 1933.10.12.137-143. Variability: The figured specimens exemplify the rather large degree of variations found in the otoliths of this species, in particular as far as outline and proportions of otoliths are concerned. One of the otoliths (fig. 451) is much more compressed than the others Discussion: Otoliths of M. antillarum are amongst the least characteristic ones to be found in this genus. In general they seem to be more rounded in outline than those of the other recent species investigated. Distribution: Off the coasts of Florida and the west Indies. Monolene sessilicauda GOODE 1881 Figs. 452 syn. Thyris pellucidus GOODE 1881 Investigated otoliths: 1 otolith (right side) from off Newport, Rhode Island, Atlantic coast of the USA, ZMH Ot. 26.5.1994.22 (leg. ZMUC, ex USNM). 198 448 450 449a 449c 449b 451 452a 452c 453 452b Figs. 448-451: Monolene antillarum NORMAN 1933 – 15 × Fig. 452: Monolene sessilicauda GOODE 1881 – 15 × Fig. 453: Monolene maculipinna GARMAN 1899 – 15 × Discussion: The single otolith of M. sessilicauda differs from those of the apparently related M. antillarum in the rectangular outline. Distribution: Off the coast of southern New England, Atlantic coast of the USA. Monolene microstoma (CADENAT 1937) Figs. 454-457 Investigated otoliths: 8 otoliths (4 right side and 4 left side) from the Atlantide Stat. 120 off Rio Muni, West Africa (02°9’N/09°7’E), ZMH Ot. 26.5.1994.23-26 (leg. BMNH 1962.6.18.13-19) and BMNH 1962.6.18.13-19. Ontogeny and variability: The otoliths of this species too show a large degree of intraspecific variability. In particularly the outline is quite variable ranging from almost rounded to round- ed with distinct pre- and postdorsal angles to trapezoidal. Sometimes an incipient rostrum is being developed. Also proportions of the otoliths are quite variable. Ontogenetic changes sort of submerge under the high degree of variability. However, smaller specimens tend to be less thickset than the larger specimens. Discussion: Due to the high degree of intraspecific variability it is very difficult to reliably define this species by means of otoliths alone. Otoliths with a trapezoidal outline bear a lot of resemblance with certain species of the genus Laeops. If found isolated they might well be mistaken as representatives of that genus. In this respect it is interesting to not that prior to the revision of NIELSEN (1961) M. microstoma was indeed regarded as a representative of Laeops. Distribution: Tropical coasts of West Africa. Schwarzhans: Pleuronectiformes 199 455 454c 454a 454b 456 457 Figs. 454-457: Monolene microstoma (CADENAT 1937) – 15 × Monolene maculipinna GARMAN 1899 Fig. 453 and absence or presence of a faint marginal crenulation. Investigated otoliths: 2 otoliths (right and left side) from the Pacific coast of Columbia (07°7’N/ 78°7’W), ZMH Ot. 27-28 (leg. SMF). Discussion: Otoliths of M. priscus are rather inconspicuous. They differ from the known recent species of the genus in their rather regularly rounded outline. The inclusion of the species in the genus Monolene has a somewhat tentative character. Discussion: The otoliths of M. maculipinna are readily recognized by their rectangular outline and their elongate shape. Distribution: Off the Pacific coast of Panama and Columbia in rather deep water. Distribution: Upper Oligocene of the Lower Rhine Valley, North Sea Basin. 7.6.8 Engyprosopon Group Monolene priscus SCHWARZHANS 1994 Figs. 458-461 syn. Monolene priscus SCHWARZHANS 1994 – SCHWARZHANS 1994: fig. 507-511 Investigated otoliths: 5 otoliths, the holotype (GPIM-M 2908, fig. 460) and 4 paratypes (GPIMM 2909-2911 and SMF P 8724, figs. 458, 459, 461) from wells in the Lower Rhine Valley near Krefeld and Erkrath, Chattian, Upper Oligocene. Ontogeny and variability: Ontogenetic changes and intraspecific variability are relatively small in this species, confined to details of the outline Piscium Catalogus, Part Otolithi piscium, Vol. 2 Genera: Four genera – Asterorhombus, Engyprosopon, Crossorhombus and Tosarhombus – distributed in the Indo-Pacific. Otoliths of Tosarhombus are not known. The genus is included in the group, because MACHIDA et al. (1984) placed it near Crossorhombus. Definition and relationship: Otoliths of the Engyprosopon Group closely resemble to those of the Arnoglossus Group. They are rather small, compact and rounded rectangular in outline. The sulcus opening is somewhat reduced. Differing from the Arnoglossus Group is the rather strongly convex and smooth inner face. In this respect 200 460a 458 460c 459 460b 461 Figs. 458-461: Monolene priscus SCHWARZHANS 1994 – 15 × otoliths of the Engyprosopon Group look morphologically intermediate between those of the Bothus Group and the Arnoglossus Group. However, unlike in the Bothus Group the sulcus is rather shallow and so are the dorsal and ventral depressions. NORMAN (1934) placed the genera of this group in the subfamily Bothinae close to Bothus. In this genera, like in the Bothus Group as well, the interorbital region is wider in males than in females. It is possible that this kind of sexual dimorphism has some impact on otolith morphology as well, as was demonstrated in the case of Syacium ovale (see entry to genus Syacium), but the few otoliths available do not allow for such investigations. In any case, NORMAN’s concept of relating the genera to Bothus is understandable and to some degree also supported by otolith morphology. However, as discussed above, the otolith pattern found in the Engyprosopon Group shows some peculiarities morphologically intermediate between the Bothus and Arnoglossus Group and thus in my opinion warrants their separation in a group of their own. Asterorhombus TANAKA 1915 Type-species: Platophrys (Arnoglossus) intermedius BLEEKER 1866 Diagnosis: Small, elongate, moderately thickset otoliths; ventral rim rather shallow, somewhat undulating, dorsal rim slightly more rounded, undulating, without prominent angles, posterior tip oblique or with slight projection, anterior rim blunt, rounded, sometimes with incipient, ventrally shifted short rostrum, but without excisura; index l:h 1.55-1.65. Otolith size probably not much exceeding 2 mm. Ostium slightly longer than cauda and slightly wider. Sulcus rather deep, narrow, anteriorly inclined, with a somewhat reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi deep, separated. Dorsal and ventral depressions narrow, not very deep, well marked towards the sulcus, more or less connected around caudal tip to form a circumsulcal depression. Inner face strongly convex in both directions, not smooth; outer face slightly concave, rather smooth. Rims moderately sharp. Measurements: intermedius l:h 1.55-1.65 h:t 2.8 ol:cl 1.1-1.5 oh:ch s.i.a. con.i 1.4-1.6 5-10° 2.4 Side dimorphism: Not apparent. Discussion: Asterorhombus probably represents the most plesiomorphic genus in the Engyprosopon Group. Its otoliths are morphologically intermediate between those of the Arnoglossus Group and the more advanced Engyprosopon Group. With the former it shares the deep and inclined sulcus, with the latter the strongly convex inner face and the very small size. Interestingly, the two species now placed in this genus had been placed in Arnoglossus (A. intermedius) and Engyprosopon (A. fijiensis) by NORMAN (1934). Species and distribution: Two species – A. intermedius, widely distributed throughout the Indian Ocean, from East Africa and the Red Sea to Australia and the Solomon Islands and A. fijiensis, from the Fiji Islands and northeastern Australia. Schwarzhans: Pleuronectiformes 201 463a 462a 463b 463c 462b Figs. 462-463: Asterorhombus intermedius (BLEEKER 1866) – 25 × Asterorhombus intermedius (BLEEKER 1866) Figs. 462-463 Investigated otoliths: 3 otoliths (two left and one right), from Lizard Island, Great Barrier Reef, Queensland, Australia, AMS I.20753-022. Discussion: An otolith from the second species – A. fijiensis – also from the Great Barrier Reef off Queensland (AMS I.22579-018) was found to be strongly affected by formalin and therefore is not figured. Anyway, it is very similar to A. intermedius, may be just slightly more compressed. Distribution: Throughout the Indian Ocean from East Africa and the Red Sea to Australia. Engyprosopon GÜNTHER 1862 Type-species: Rhombus mogkii BLEEKER 1854 syn. Scaeops JORDAN & STARKS 1904 (type-species: Rhombus grandisquama) Diagnosis: Small, thickset otoliths with a rounded, oval outline; ventral rim gently and moderately deep curving, dorsal rim less curving, usually with a rounded predorsal angle, posterior tip rounded or oblique, then with its tip shifted dorsally, anterior rim blunt, rounded, sometimes with incipient short rostrum, but without excisura; index l:h 1.2-1.7. Otolith size rarely up to 3 mm. Ostium considerably longer than cauda and slightly wider. Sulcus rather shallow, sometimes slightly inclined, with a somewhat reduced ostial opening. Cauda terminating at moderate distance Piscium Catalogus, Part Otolithi piscium, Vol. 2 from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions narrow, rather shallow, but well marked towards the sulcus, more or less connected around caudal tip to form a circumsulcal depression. Inner face rather strongly convex and relatively smooth; outer face flat, smooth. Rims moderately sharp, smooth. Measurements: xenandrus (right) xenandrus (left) filimanus (right) cocosensis (right) grandisquama (r) bleekeri (right) l:h 1.35 1.50-1.70 1.30 1.25 1.20 1.20 h:t ol:cl oh:ch s.i.a. 2.6 1.4 1.1 5° 2.6 1.6-1.8 1.1-1.2 5-10° nm 1.6 1.1 5° 2.5 0.8 1.1 20° 2.4 1.3 1.0 0-5° 3.2 1.5 1.0 0-5° con.i 3.0 3.0 nm 3.2 2.0 3.7 Side dimorphism: Left hand otoliths usually are considerably more elongate than right hand otoliths. This is mainly due to the development of an incipient rostrum and a somewhat more pointed posterior tip. This is particularly obvious in E. xenandrus, the only species from which a larger series of otoliths is available. Apart from this, the index ol:cl is also larger in left hand otoliths. Variability: Variability is less conspicuous due to the relatively high degree of side dimorphism. Discussion: Engyprosopon apparently is related to Crossorhombus. Generally it seems, that otoliths of Engyprosopon are somewhat more thickset. However, only few species have been investigated and with more knowledge it may become difficult to reliably differentiate between otoliths of the two genera. 202 464a 465 464c 466 467 464b 468c 468a 468b Figs. 464-466: Engyprosopon ×enandrus GILBERT 1905 – 15 × Fig. 467: Engyprosopon filimanus (REGAN 1908) – 15 × Fig. 468: Engyprosopon cocosensis (BLEEKER 1855) – 15 × Species and distribution: Engyprosopon is a specious genus with some 27 species reported and widely distributed throughout the Indo-Pacific, from South Africa into the Red Sea, to Hawaii and the Easter Islands. They are (listing possibly not complete) – E. arenicola, E. bellonaensis, E. bleekeri, E. borneensis, E. cocosensis, E. filimanus, E. grandisquama, E. hawaiiensis, E. hensleyi, E. hureaui, E. latifrons, E. longipelvis, E. longipterum, E. macrolepis, , E. macroptera, E. maldivensis, E. mogkii, E. multisquama, E. natalensis, E. raoulensis, E. regani, E. rostratum, E. sechellensis, E. septempes, E.smithi, E. xenandrus, E. xystrias. Several of these species are known only from the holotype or else very few specimens. Otoliths are only known from five species, namely E. xenandrus, E. filimanus, E. cocosensis, E. bleekeri and E. grandisquama. Engyprosopon xenandrus GILBERT 1905 Figs. 464-466 Investigated otoliths: 6 otoliths (3 right side and 3 left side) from Hawaii, ZMH Ot. 27.5.1994.1-6 (leg. Fitch). Discussion: Otoliths of E. xenandrus are more elongate than those of the other two investigated species. Distribution: Hawaiian Islands, in rather deep water. Engyprosopon filimanus (REGAN 1908) Fig. 467 Investigated otoliths: 3 otoliths (right side) from off Muscat, Sea of Oman, ZMH Ot. 27.5.1994.7-8 (leg. BMNH 1904.5.25.78-80) and BMNH 1904. 5.25.78-80. Discussion: Otoliths of E. filimanus are rather compressed with a conspicuous rectangular outline. Distribution: The types of E. filimanus have been collected from the Maldives Islands. The otoliths have been extracted from fishes collected in the Sea of Oman. Their specific identification was marked with a question mark by NORMAN (1934). Schwarzhans: Pleuronectiformes 203 469c 469a 470a 470c 470b 469b Fig. 469: Engyprosopon grandisquama (TEMMINCK & SCHLEGEL 1846) – 15 × Fig. 470: Engyprosopon bleekeri (MACLEAY 1882) – 15 × Engyprosopon cocosensis (BLEEKER 1855) Fig. 468 Investigated otoliths: 1 otolith (right side) from the Nicobar Islands, BMNH 1927.1.6.33-37. Discussion: In its compressed rectangular outline this otolith resembles E. filimanus. Very characteristic is the steeply inclined sulcus and the unusually short ostium (see index ol:cl). Distribution: Nicobar Islands and coasts of India and Burma. Engyprosopon grandisquama (TEMMINCK & SCHLEGEL 1846) Fig. 469 syn. Rhombus poecilurus BLEEKER 1852 syn. Rhomboidichthys spilurus GÜNTHER 1880 syn. Scaeops orbicularis JORDAN & SEALE 1907 Investigated otoliths: 2 otoliths (right and left side) from the Gulf of Manaar, Ceylon, ZMH Ot.910 (leg. ZMH 19950). Distribution: E. grandisquama is a widely distributed and apparently rather common species known from South Africa through the Indian Ocean to Indonesia, Australia and Japan. Engyprosopon bleekeri (MACLEAY 1882) Fig. 470 Investigated otoliths: 1 otolith (right side) from Nagasaki, Japan, BMNH 1933.6.12.3. Discussion: Very similar in habitus to E. grandisquama, but with a deeper ventral rim and a shallower dorsal rim with pronounced postdorsal angle. Distribution: NE Australia to southern Japan. Tosarhombus AMAOKA 1969 Type-species: Tosarhombus octoculatus AMAOKA 1969 Side dimorphism: Side dimorphism in this species is much less apparent than in E. xenandrus. Remarks: Otoliths of Tosarhombus have not been available for investigation. The genus is placed in the Engyprosopon Group because of its close allocation with Engyprosopon and Crossorhombus in MASUDA et al. (1984). Discussion: Otoliths of E. grandisquama are relatively well rounded in outline, but with a rather prominent predorsal angle, and very compressed. Species and distribution: Tosarhombus is a monospecific genus with T. octoculatus restricted to the coasts of Japan. Piscium Catalogus, Part Otolithi piscium, Vol. 2 204 Crossorhombus REGAN 1920 Type-species: Platophrys dimorphus GILCHRIST 1905 (syn. C. valderostratus) Crossorhombus valderostratus (ALCOCK 1890) Figs. 471-472 Diagnosis: Small, thin to moderately thickset otoliths with a rounded, oval outline; ventral rim rather shallow, dorsal rim shallow too, variably with a rounded pre- and/or postdorsal angles, posterior tip rounded or cut, anterior rim rounded, sometimes with incipient short rostrum, but without excisura; index l:h 1.4-1.5. Otolith size rarely up to 3 mm. Ostium considerably longer than cauda and slightly wider. Sulcus rather shallow to moderately deep, not inclined, with a somewhat reduced ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi well separated. Dorsal and ventral depressions narrow, usually rather shallow, but well marked towards the sulcus, more or less connected around caudal tip to form a circumsulcal depression. Inner face moderately convex and relatively smooth; outer face flat to slightly convex, smooth. Rims moderately sharp, smooth. syn. Platophrys dimorphus GILCHRIST 1905 syn. Scaeops kobensis JORDAN & STARKS 1906 syn. Scaeops ui TANAKA 1918 Measurements: Investigated otoliths: 1 otolith (left side) from off Hongkong, IRSNB (coll. Nolf, leg. Stinton). Discussion: This relatively thin otolith is characterized by its incipient rostrum. l:h valderostratus 1.35-1.50 azureus 1.50 kanekonis 1.35-1.40 h:t 2.3 3.1 2.6 ol:cl 1.5-1.7 1.7 1.8 oh:ch 1.3-1.4 1.4 1.1 s.i.a. 0° 0-5° 0° con.i 2.7 3.8 4.3 Investigated otoliths: 2 otoliths (right and left side) from the Mikawa Bay, Japan, coll. Ohe #79815-43. Discussion: Otoliths of C. valderostratus are rather thickset and show a rounded rectangular outline. Distribution: C. valderostratus is widely distributed throughout the Indo-Pacific, from East Africa to China and Japan. Crossorhombus azureus (ALCOCK 1889) Fig. 473 syn. Platophrys microstoma WEBER 1913 Side dimorphism: Side dimorphism is moderately developed in C. valderostratus, but absent in C. kanekonis. When developed, left hand otoliths are slightly more elongate than right hand otoliths, separation of colliculi is less obvious and the otolith is slightly less thickset. Distribution: SE-India, Ceylon, Indo-China, China and Aru Islands. Ontogeny: The investigated otoliths of C. kanekonis are somewhat smaller than those of the two other species (2 mm versus 3 mm) and show some delicate marginal crenulation. It is quite possible that this reflects ontogeny. Investigated otoliths: 2 otoliths (right and left side) from Enshu Nada, Central Japan, coll. Ohe #78726-32. Discussion: Crossorhombus is closely related to Engyprosopon (see respective entry for detailed discussion). Species and distribution: Crossorhombus contains four recent species from the Indo-Pacific – C. valderostratus, C. azureus, C. kanekonis, C. howensis. Crossorhombus kanekonis (TANAKA 1918) Figs. 474-475 Discussion: These small and rather thin otoliths are characterized by their rather regularly rounded outline and the delicate marginal crenulation. The latter, however, could well represent an ontogenetic effect. Distribution: Japan and Taiwan. Schwarzhans: Pleuronectiformes 205 472a 471a 471d 471c 472b 471b 473a 472c 473b 475 474c 474b 473c 474a Figs. 471-472: Crossorhombus valderostratus (ALCOCK 1890) – 15 × Fig. 473: Crossorhombus azureus (ALCOCK 1889) – 15 × Figs. 474-475: Crossorhombus kanekonis (TANAKA 1918) – 15 × 7.6.9 Thysanopsetta Group Genera: Thysanopsetta. Definition and relationship: The small, compact otoliths of the genus Thysanopsetta are unique in several aspects. They exhibit a deep excisura and a relatively strong rostrum and antirostrum. The sulcus is deeply cut and so are the narrow dorsal and ventral depressions which are perfectly connected around the caudal tip. The portion around the sulcus is strongly elevated against the rest of Piscium Catalogus, Part Otolithi piscium, Vol. 2 the inner face. Thus the otoliths do not resemble any of the other Bothidae. Only a certain overall resemblance to the Bothus or the Mancopsetta Groups could be thought of, but this may as well be purely accidental. As it stands now, Thysanopsetta is somewhat isolated from the rest of the Bothidae and its relationship is obscure. I have therefore selected to place it into an otolith group of its own. Apparently NORMAN (1934) felt similar. He stated that “the relationships of this genus (Thysanopsetta) are somewhat obscure, but it may 206 477 476c 476a 476b Figs. 476-477: Thysanopsetta naresi GÜNTHER 1880 – 15 × conveniently be placed near Tephrinectes”. Otolith morphology, however, strongly contradicts any relationship with Tephrinectes (see respective entry). Thysanopsetta GÜNTHER 1880 Type-species: Thysanopsetta naresi GÜNTHER 1880 Diagnosis: Small, rather thickset and compact otoliths with a rounded, oval outline; all rims gently curving, except for the anterior rim, which shows a deep excisura and marked rostrum and antirostrum; index l:h about 1.4. Otolith size less than 3 mm. Ostium longer than cauda and wider too. Sulcus very deep, with a clear ostial opening. Cauda terminating at moderate distance from posterior tip of otolith. Colliculi separated, deepened. Dorsal and ventral depressions narrow, very deep and sharp, well connected around caudal tip to form a circumsulcal depression. Inner face markedly convex, area around sulcus considerably elevated; outer face slightly convex, smooth. Rims moderately sharp, smooth. Measurements: naresi l:h 1.40-1.50 h:t 2.0 ol:cl 1.8 oh:ch 1.2-1.3 con.i 2.0 Side dimorphism: The left hand otolith is slightly more elongate than the right hand otolith. Species and distribution: A single species – T. naresi – from the Magellan-Falkland Islands region of south-eastern South America. Thysanopsetta naresi GÜNTHER 1880 Figs. 476-477 Investigated otoliths: 3 otoliths, 2 otoliths (right and left side) from off Cape Virgins, Argentina, ZMH Ot. 28.5.1994.1 (leg. BMNH 90.2.26.161) and BMNH 90.2.26.161, 1 otolith (right side) from off Punta Arenas, Argentina, ZMH Ot. 28.5.1994.2 (leg. ZMH Ot. 20006). Discussion and distribution: See entries to genus and group. 7.6.10 Chascanopsetta Group Genera: Three genera – Chascanopsetta, Pelecanichthys, Kamoharaia – from the deep waters of the Indo-Pacific. Otoliths are only known from the genus Chascanopsetta. Definition and relationship: The fishes of the three genera placed in this group are readily recognized by their extremely enlarged mouth. This character has also been used to separate the two monospecific genera Pelecanichthys and Kamoharaia from Chascanopsetta. CHABANAUD (1939) has questioned the value of this single character, which is typical (autapomorphic) for the group as such, to be used in this sense. He regarded Pelecanichthys as synonym of Chascanopsetta (Kamoharaia was not erected then). I find his argumentation quite convincing, but without additional otolith material it can not be tested. Otoliths of Chascanopsetta show an extraordinary strong side dimorphism affecting almost all possible characters. The left hand otolith differs from the right hand otolith in the longer sulcus, the clear ostial opening, the outline of the otolith (in particular the presence of a massive rostrum), the presence of a faint excisura (but no antiros- Schwarzhans: Pleuronectiformes 207 478 479c 479a 479b Figs. 478-479: Chascanopsetta lugubris ALCOCK 1894 – 15 × trum) and the more narrow circumsulcal depression. Taking the left hand otolith as the more typical, which reflects an inversion of the usual type of side dimorphism, the otoliths are further characterized by their small, compressed size and the rather flat inner face. They do not particularly resemble any of the other bothid otolith groups and that is the reason why I have placed these genera in an otolith group by themselves. Chascanopsetta ALCOCK 1894 Type-species: Chascanopsetta lugubris ALCOCK 1894 syn. Trachypterophrys FRANZ 1910 (type-species: T. raptator, syn. C. lugubris) Diagnosis: Small, moderately thickset otoliths with aa irregularly rounded outline; ventral rim shallow, gently curving, dorsal rim much higher, somewhat irregularly undulating, sometimes with faint pre- and postdorsal angles, posterior tip blunt, rounded to slightly pointed inframedianly, anterior tip blunt in right hand otoliths, with massive rostrum and faint excisura in left hand otoliths; index l:h 1.25. Otolith size less than 3 mm. Ostium longer than cauda and slightly wider. Sulcus moderately deep, with a clear ostial opening in left hand otoliths and somewhat reduced opening in right hand otoliths. Cauda terminating at some distance from posterior tip of otolith. Colliculi separated, deepened. Dorsal and ventral depressions moderately deep, well marked towards the sulcus and well connected around caudal tip to form a circumsulcal depression. Inner face almost flat, area around sulcus slightly elevated; outer face slightly convex, smooth. Rims moderately sharp, smooth. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Measurements: lugubris (right) lugubris (left) l:h 1.25 1.25 h:t 3.0 3.0 ol:cl 1.6 2.1 oh:ch 1.1 1.8 con.o 3.0 3.0 Side dimorphism: See diagnosis to genus and discussion to group. Discussion: See discussion to group. Species and distribution: There are 8 nominally valid species in this genus from the deeper waters of the Indo-Pacific – C. lugubris, C. normani, C. megagnatha C. microstoma, C. prognathus, C. prorigera, C. galathaea, C. micrognathus. Chascanopsetta lugubris ALCOCK 1894 Figs. 478-479, 17 syn. Trachypterophrys raptator FRANZ 1910 syn. Chascanopsetta gilchristi VON BONDE 1922 syn. Chascanopsetta maculata VON BONDE 1922 Investigated otoliths: 2 otoliths (right and left side) from W off Ceylon, ZMH Ot. 28.5.1994.3 (leg. BMNH 1927.1.6.53) and BMNH 1927.1.6.53. Side dimorphism: See entry to genus and group. Distribution: C. lugubris is the most common and most widely distributed species of the genus, the other species known from very few specimens or types only. It is known from SE-Africa through the Indo-Pacific to Japan. Pelecanichthys GILBERT & CRAMER 1897 Remarks: Otoliths of Pelecanichthys are not known. Paratypes kept in the BMNH were found with completely dissolved otoliths. 208 481a 480 481c 481b 482 Figs. 480-482: Mancopsetta milfordi PENRITH 1965 – 10 × Species and distribution: Pelecanichthys is a monospecific genus with P. crumenalis restricted to the deep water around the Hawaiian Islands. Kamoharaia KURONAMA 1940 Type-species: Chascanopsetta megastoma KAMOHARA 1936 Species and distribution: The single species – K. megastoma – is known from the unique holotype from off Japan and a small postlarval taken in the Philippine Sea (NIELSEN, 1963). Otoliths have not been available for investigation. Likewise, the relationship of these fishes based on ichthyological analyses has been disputed in recent literature. EVSEENKO (1984) has proposed the family Achiropsettidae for these two genera based on a number of unique characters found in the fishes. These are the median position of the vent in front of the anal fin, the position of the tip of the dorsal fin behind the posterior nostril of the blind side and the loss of pectoral fins. Although otolith analysis supports the concept of Mancopsetta and Achiropsetta to be somewhat separated from the main body of the Bothidae, I do not feel for the necessity to put them in a separate family altogether. The general appearance of the otoliths still is in line with a number of other aberrant Bothidae (see above). 7.6.11 Mancopsetta Group Genera: Two genera from the Subantarctic and Antarctic waters – Mancopsetta and Achiropsetta. Otoliths are only known from Mancopsetta. Mancopsetta GILL 1881 Type-species: Lepidopsetta maculata GÜNTHER 1880 Definition and relationship: Otoliths of Mancopsetta are easily recognized by their high, rounded, almost circular outline, the strong rostrum and the marked excisura. The ostium is only slightly longer than the cauda. The colliculi are well separated and deepened. Superficially, Mancopsetta otoliths somewhat resemble Chascanopsetta and even Thysanopsetta otoliths, but most of the characters listed above exemplify their separate position. In fact the relationships of these otoliths to other Bothidae remains obscure. syn. Lepidopsetta GÜNTHER 1880 (preoccupied by Lepidopsetta GILL 1864, a genus of Pleuronectidae, type-species: L. maculata) syn. Apterygopectus OJEDA 1978 (type-species: A. avilesi, syn. M. milfordi) syn. Neachiropsetta KOTLYAR 1978 (type-species: Mancopsetta milfordi) ?syn. Pseudomancopsetta EVSEENKO 1984 (typespecies: P. andriashevi) Schwarzhans: Pleuronectiformes 209 484 483c 483b 483a Figs. 483-484: Mancopsetta maculata (GÜNTHER 1880) – 10 × Diagnosis: Moderately large and not very thickset otoliths with a high, rounded, nearly circular outline, from which only the massive rostrum sticks out; all rims gently curving, usually somewhat undulating; the massive rostrum accompanied by a marked excisura; index l:h 1.05-1.35. Otolith size up to 4 mm. Ostium slightly longer than cauda, not wider. Sulcus deep, with a clear ostial opening. Cauda terminating at some distance from posterior tip of otolith. Colliculi well separated, strongly deepened. Dorsal and ventral depressions narrow, often indistinct, but well connected around caudal tip to form a circumsulcal depression. Inner face flat to slightly convex, rather smooth; outer face slightly convex, smooth to slightly undulating. Rims moderately sharp, smooth to undulating. l:h 1.05-1.10 1.30-1.35 syn. Apterygopectus avilesi OJEDA 1978 Investigated otoliths: 3 otoliths (2 right side and 1 left side) from off southern New Zealand, ZMH Ot. 28.5.1994.4-6 (coll. Schwarzhans). Discussion: Otoliths of M. milfordi are more compressed, higher than those of M. maculata. Distribution: On the continental shelf and upper slope off southern New Zealand and the southern tip of South America and Islands and Seamounts in the Subantarctic. Mancopsetta maculata (GÜNTHER 1880) Figs. 483-484 Measurements: milfordi maculata Mancopsetta milfordi PENRITH 1965 Figs. 480-482, 18 h:t 2.9 3.4 ol:cl 1.2-1.5 1.1-1.3 oh:ch 0.85-1.0 0.95-1.0 con.i 4.5 5.0 Side dimorphism: Side dimorphism is moderate in the species of Mancopsetta. In left hand otoliths the excisura is usually deeper, the shape may be slightly more elongate or more regularly rounded. Variability: Intraspecific variations are moderate too, mainly restricted to details of the outline. Discussion: See entry to group. Species and distribution: There are 2, possibly 3 species from Antarctic and Subantarctic waters – M. maculata, M. milfordi and M. andriashevi (the latter when accepting Pseudomancopsetta as a synonym). Piscium Catalogus, Part Otolithi piscium, Vol. 2 syn. Achiropsetta slavae ANDRIASHEV 1960 syn. Mancopsetta antarctica KOTLYAR 1978 Investigated otoliths: 2 otoliths (right and left side) from off Falkland Islands, ZMH Ot. 28.5.1994.7 (leg. BMNH 1930.5.6.41) and BMNH 1930.5.6.41. Discussion: Otoliths more elongate than in M. milfordi. Distribution: Shelf and slope off southernmost North America, Islands and Seamounts of the Subantarctic and coasts of Antarctica. This is the only flatfish caught at the Antarctic coasts. 210 Achiropsetta NORMAN 1930 Type-species: Achiropsetta tricholepis NORMAN 1930 Species and distribution: Achiropsetta apparently is closely related to Mancopsetta. It is a monospecific genus with A. tricholepis known from the upper slope off the southernmost tip of South America, off southern New Zealand and Islands and Seamounts of the Subantarctic. Otoliths have not been available for investigation. The type specimen in the BMNH collection apparently represents a postlarval form. It is nearly translucent and upon close examination it seemed that otoliths were dissolved. 7.7 Pleuronectidae Genera: The Pleuronectidae contain some 37 recent genera in the limits as presented here. In alphabetical order they are the following: Acanthopsetta, Atherestes, Azygopus, Cleisthenes, Clidoderma, Dexistes, Embassichthys, Eopsetta, Glyptocephalus, Hippoglossoides, Hippoglossus, Hypsopsetta, Inopsetta, Isopsetta, Kareius, Lepidopsetta, Limanda, Liopsetta, Lyopsetta, Marleyella, Microstomus, Nematops, Parophrys, Pelotretis, Plagiopsetta, Platichthys, Pleuronectes, Pleuronichthys, Poecilopsetta, Psettichthys, Pseudopleuronectes, Reinhardtius, Rhombosolea, Samaris, Samariscus, Tanakius, Verasper. In addition, there are three monotypic genera, which need revision and their generic status verified: Pluviopsetta TANAKA 1916, Pseudoplatichthys HIKITA 1934 and Neoetropus HILDEBRAND & SCHRÖDER 1928. Definition and relationship: NORMAN (1934) understood the Pleuronectidae as an assemblage containing all left eyed Pleuronectoidei, including the Brachypleuridae, as well as the genera which I have placed here in the Paralichthodes and Ammotretis Groups of uncertain familial relationship. He distinguished 5 subfamilies – Pleuronectinae, containing more than half of the total number of genera, Poecilopsettinae, Paralichthodinae, Samarinae and Rhombosoleinae – based on a variety of characters such as symmetry of pelvic fins, anterior origin of dorsal fin, status of lateral line on blind side and other characters. HUBBS (1945) excluded Brachypleura and Lepidoblepharon from the Samarinae (where they were placed by NORMAN) and included them in the Citharidae (in the present study they are thought to represent a separate family). NORMAN’S monogeneric Paralichthodinae are here excluded as well (see Paralithodes Group). Similar views have also been discussed by HENSLEY & AHLSTROM (1984) and CHAPLEAU (1993). Based on otoliths, the Rhombosoleinae sensu NORMAN are not thought to represent a natural group. The genera of NORMAN’s Rhombosoleinae are divisible into: three groups within the Pleuronectidae (Pelotretis Group, Rhombosolea Group and the genus Azygopus with the Samaris Group), one group of uncertain relationship (the Ammotretis Group with several genera) and one genus (Peltorhamphus) excluded from the Pleuronectoidei and placed in the Soleidae (Heteromycteris Group, see respective entry). Only the Pelotretis and Rhombosolea Groups may remain in the much reduced subfamily Rhombosoleinae. The reasoning behind splitting the Rhombosoleinae is given in detail in chapter 5.3.2. NORMAN (1934) roughly subdivided his Pleuronectinae into two generic groups. One was to be characterized by a large and symmetrical mouth (tribe Hippoglossini in NELSON 1994) and it included genera placed here in the Hippoglossus and the Hippoglossoides Groups as well as Psettichthys of the Isopsetta Group. The other group was characterized by a small mouth with asymmetrical jaws and dentition (tribe Pleuronectini in NELSON 1994) and it included genera placed in the Glyptocephalus, Pleuronectes-Limanda, Isopsetta and Microstomus-Pleuronichthys Groups. The two genera of the Verasper Group were thought to be somehow intermediate between the two groups. Following the analysis of the otolith morphology I find this bipartition of the Pleuronectinae phylogentically not sound. No doubt the genera with a large and symmetrical mouth represent a plesiomorphic condition, but the various fishes found in NORMAN’s group with a small and asymmetrical mouth are seemingly the result of several different lineages of specialization not necessarily related to each other and probably derived separately from plesiomorphic groups (further details will be discussed in the general entries to the various groups). Otoliths of the Pleuronectidae exhibit a wide range of morphological patterns that do not allow for a simple definition of the family. With the Bothidae, the Pleuronectidae share most of the advanced pleuronectiform otolith patterns such as the completely developed circumsulcal depresSchwarzhans: Pleuronectiformes 211 sion and the rather short cauda. In fact, in comparison with the ostium the cauda is often more strongly reduced in Pleuronectidae than in Bothidae. Also, most genera constituting the core of the Pleuronectidae (Pleuronectinae in NORMAN 1934) are characterized by a strong reduction of the ostial opening. However, well developed ostial openings, sometimes even with an excisura, are also found (Microstomus-Pleuronichthys, Samaris and Poecilopsetta Groups). Except for these latter groups the sulcus is shallow to very shallow and the otoliths are thin with a slightly convex inner face and a concave to flat outer face. In the three groups already mentioned the sulcus is deep to extremely deep and the otoliths are robust. As a result, there is considerable morphological overlap in the otoliths of the two families Pleuronectidae and Bothidae and the appropriate placement of otoliths in the one or other family will often depend very much on correlation at generic or group level. Then, however, the taxonomic problem can be solved quite reliably in most cases. The degree of side dimorphism in pleuronectid otoliths is often considerably and affects a large variety of characters. With the possible exception of Azygopus, there is not a single genus in this family without more or less well developed side dimorphism in the otoliths. Those of Reinhardtius are amongst the most extreme examples of side dimorphism found in any otoliths. In this treatise the 37 genera of the Pleuronectidae are organized in 12 informal genus groups exhibiting similar otolith morphologies. These genus groups are assigned to 4 informal subfamilies. The groups are: Hippoglossus, Hippoglossoides, Glyptocephalus, Pleuronectes-Limanda, Isopsetta, Verasper, Microstomus-Pleuronichthys, Samaris, Marleyella, Poecilopsetta, Pelotretis and Rhombosolea Groups. The first five (Hippoglossus, Hippoglossoides, Glyptocephalus, PleuronectesLimanda and Isopsetta Groups) represent the core of NORMAN’s Pleuronectinae and could be described as the “typical” forms to be found within Pleuronectidae. They are all characterized by a reduced ostial opening, a very small cauda, a shallow sulcus and thin otoliths with a flat to slightly concave outer face. Also the Pelotretis and Rhombosolea Groups (making up the Rhombosoleinae) are quite similar except for the ostial opening which is less reduced. The Verasper and Microstomus-Pleuronichthys Groups (also from NORMAN’s Pleuronectinae) stand somewhat apart Piscium Catalogus, Part Otolithi piscium, Vol. 2 from this cluster of groups in possessing a deep sulcus with a clear ostial opening. In the otoliths of the Samaris Group (sole group of the Samarinae) this trend is taken to its extremes. Here, we find the deepest sulci within the Pleuronectiformes, a deeply cut excisura where the ostium opens anteriorly and very robust otoliths. Finally, the Marleyella and Poecilopsetta Groups constitute a small cluster of more distantly related genera. Marleyella probably represents the most plesiomorphic morphology within this cluster and the otoliths show a remarkable resemblance to those of certain citharids. This indicates, that the two groups either represent a very early divergence from the main branch of the Pleuronectidae or are of pre-pleuronectid origin altogether. Following the traditional classification they are here placed under Poecilopsettinae in the Pleuronectidae. Based on osteological investigations, such as the hypural patterns, HENSLEY & AHLSTROM (1984) have questioned the monophyly of Pleuronectidae. Furthermore, they concluded that Pleuronectinae are more closely related to Bothidae (s.l., here Paralichthyinae) and that Samarinae and Poecilopsettinae might be of different origin. CHAPLEAU (1993) even proposed raising Samarinae to family status. In conclusion, several genus groups or clusters of pleuronectid genus groups can be well defined by means of otoliths, as for instance the core of NORMAN’s Pleuronectinae or his Samarinae (Samaris Group), whereas others are not so obvious (Verasper, Microstomus-Pleuronichthys and Marleyella Groups). Also, there is no single character found in otoliths to define Pleuronectidae as a whole and therefore assignment of a certain otolith to this family has to rely on careful correlation at generic or group level. Even after the exclusion of Paralichthodes and several genera of the former Rhombosoleinae from the Pleuronectidae the family is probably still polyphyletic (see above). Samarinae and Poecilopsettinae are likely further candidates for exclusion. The remainder, the Pleuronectinae (auctt.), indeed could be allocated more closely to the Paralichthyinae in the sense of HENSLEY & AHLSTROM (1984). Distribution: Except for the tropical Samaris, Marleyella and Poecilopsetta Groups the Pleuronectidae show a distinct antitropical distribution pattern. The pleuronectine groups are restrict- 212 ed to the temperate and subtropical waters of the North Atlantic and North Pacific and the Pelotretis and Rhombosolea Groups (Rhombosoleinae) are endemic to the temperate seas of New Zealand and southern Australia. Fishes of the Poecilopsetta Group occur in deeper water. Pleuronectinae 7.7.1 Hippoglossus Group Genera: This group contains the two genera Eopsetta and Hippoglossus. Definition and relationship: Within the cluster of groups representing the core of the Pleuronectinae (NORMAN, 1934) otoliths of this group probably represent the most plesiomorphic character status. This is mainly evident from a not yet so strongly reduced ostial opening and the lack of specialized sulcus development as observed in the following groups (see respective entries). The cauda is short and small, the otoliths thin, with a slightly convex inner face and a slightly concave outer face. Otoliths are rather elongate in shape. The sulcus is relatively long, reaching close to the posterior tip of the otolith, thus leaving little space for the connection of the circumsulcal depression around the tip of the cauda. The degree of side dimorphism is moderate. It concerns details of outline and ornamentation of the otolith and loss of clear separation of the colliculi in otoliths of the eyed side. As do the fishes of this group (Hippoglossus is the largest Pleuronectiform) otoliths grow fairly big reaching up to 15 m. The Hippoglossus Group falls in NORMAN’s category of Pleuronectinae with a large and symmetrical mouth. The Hippoglossoides Group seems to be closely related to the Hippoglossus Group and probably has developed from it. Otoliths of the Hippoglossoides Group differ in the somewhat shortened sulcus, the flat inner face and the individually deepened colliculi. Also, the PleuronectesLimanda Group may have evolved from near the Hippoglossus Group and merely differs in the somewhat more reduced ostial opening and the shorter sulcus. Eopsetta JORDAN & GOSS 1887 Type-species: Hippoglossoides jordani LOCKINGTON 1880 syn. Xystrias JORDAN & STARKS 1904 (typespecies: Hippoglossus grigorjewi) Diagnosis: Thin, elongate otoliths; ventral rim shallow, gently curving, deepest behind the middle, dorsal rim with postdorsal angle, somewhat undulating, posterior tip blunt to irregularly rounded, anterior tip strongly projecting like a rostrum, rounded. Index l:h 1.6 to 1.8. Otolith size at least 7 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 1.7 to 2.0. Ostial opening pseudoostial. Cauda short, with rounded termination at some distance from the posterior rim of the otolith. Sulcus relatively shallow. Circumsulcal depression completely connected but rather shallow. Inner face flat in the horizontal direction and slightly convex in the vertical direction; outer face slightly concave and rather smooth. Rims sharp, ventrally smooth, dorsally somewhat undulating. Measurements: jordani l:h 1.60-1.80 h:t 3.5 ol:cl 1.70-2.00 oh:ch 1.1-1.2 con.i about 10 Side dimorphism: Otoliths of the eyed side show smoother dorsal and posterior rims but a much more strongly developed postdorsal angle. Ostium and cauda are less clearly differentiated, almost completely fused, and the sulcus as such is deeper. The circumsulcal depression is less clearly developed, particularly so its ventral portion. Discussion: Otoliths of the genus Eopsetta differ from those of Hippoglossus in the shorter sulcus and some details of the outline. They also closely resemble certain genera of the Pleuronectes-Limanda Group, thus indicating a close relationship. Species and distribution: Two species – E. jordani from the Pacific coast of North America and E. grigorjewi from Japan, Korea and Taiwan. Schwarzhans: Pleuronectiformes 213 485a 486 485c 485b 487 488 Figs. 485-488: Eopsetta jordani (LOCKINGTON 1880) – 6 × Eopsetta jordani (LOCKINGTON 1880) Figs. 485-488 Investigated otoliths: 4 otoliths (left and right) from off Acapulco, Mexico, Pacific coast, ZMH Ot. 21.1.1995.1-4 (leg. Fitch). Distribution: Pacific coast of North America, USA and northern Mexico, also recorded as fossil from the Pleistocene of California. Hippoglossus CUVIER 1817 Type-species: Pleuronectes hippoglossus LINNAEUS 1758 Diagnosis: Thin, elongate otoliths; ventral rim very shallow, gently curving, deepest behind the middle, dorsal rim with postdorsal and predorsal angles, posterior tip blunt, anterior tip moderately projecting like a rostrum, blunt, rounded. Index l:h 1.6 to 1.7. Otolith size at least 15 mm. Ostium wider than cauda and much longer. Index ol:cl 1.8 to 2.0. Ostial opening pseudoostial. Cauda short, with rounded termination not very far from the posterior rim of the otolith. Sulcus relatively shallow. Circumsulcal depression not completely connected behind caudal tip and rather shallow. Inner face flat in the horizontal direction and slightly convex in the vertical direction; outer face slightly concave and with fine radial furrows. Rims sharp, moderately to intensely crenulated. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Measurements: hippoglossus stenolepis l:h 1.60-1.65 1.70-1.80 h:t 5.4 4.0 ol:cl 1.80 1.85 oh:ch 1.2-1.4 1.0-1.2 con.i about 10 about 10 Side dimorphism: Side dimorphism is moderately developed. Otoliths of the eyed side show slightly smoother rims, ostium and cauda are less clearly differentiated, almost completely fused, and the sulcus as such is deeper. The circumsulcal depression is less clearly developed, particularly so its ventral portion. Discussion: Otoliths of the genus Hippoglossus are easily recognized by their long sulcus, which reaches rather closely to the posterior tip of the otolith. Species and distribution: Two species – H. hippoglossus from the North Atlantic and H. stenolepis from the North Pacific. Fishes of the genus Hippoglossus are active predators often caught in midwater. Hippoglossus hippoglossus (LINNAEUS 1758) Figs. 489-490 syn. syn. syn. syn. syn. syn. syn. Hippoglossus Hippoglossus Hippoglossus Hippoglossus Hippoglossus Hippoglossus Hippoglossus vulgaris FLEMING 1828 septentrionalis THON 1831 maximus GOTTSCHE 1835 gigas SWAINSON 1839 ponticus BONAPARTE 1846 americanus GILL 1864 linnei MALM 1877 214 490a 489a 489b 490b 492a 491a 492b 491b Figs. 489-490: Hippoglossus hippoglossus (LINNAEUS 1758) – 4 × Figs. 491-492: Hippoglossus stenolepis SCHMIDT 1904 – 4 × Investigated otoliths: 2 otoliths (left and right) from the North Atlantic, Meteor St. 814, ZMH Ot. 21.1.1995.5-6 (leg. W. Schmidt). Discussion: H. hipoglossus differs from H. stenolepis in the more massive predorsal angle and the shorter and blunter rostrum. Discussion: See entry to H. hippoglossus. Distribution: North Pacific, Bering Sea, Okhotsk Sea, and Alaska to California (there also as fossil from the Pleistocene). 7.7.2 Hippoglossoides Group Distribution: North Atlantic as far north as Spitzbergen and Greenland. Hippoglossus stenolepis SCHMIDT 1904 Figs. 491-492 Investigated otoliths: 2 otoliths (left and right) from the Bering Sea, ZMH Ot. 21.1.1995.7-8 (leg. Fitch). Genera: 6 genera are placed in this group – Atherestes, Cleisthenes, Lyopsetta, Acanthopsetta, Hippoglossoides and Reinhardtius from the North Atlantic and the North Pacific. Definition and relationship: The otoliths of the genera combined in the Hippoglossoides Group are relatively easily recognized by their extremely flat and smooth inner face, the rather short sulcus with its individually deepened and well separatSchwarzhans: Pleuronectiformes 215 ed colliculi and the very wide and well developed circumsulcal depression. Side dimorphism is developed variably, from feeble as in Atherestes to one of the most prominent expressions as in Reinhardtius (see entries to genera). The Hippoglossoides Group represents a morphologically well defined and dense cluster of genera probably having descended from near the Hippoglossus Group. Like this group, the Hippoglossoides Group belongs to NORMAN’s category of Pleuronectinae with a large and symmetrical mouth. Also closely related probably is the Glyptocephalus Group, which differs merely in showing more compressed otolith shapes. Side dimorphism: Side dimorphism in otoliths of Atherestes is only mildly developed. Otoliths of the eyed side are slightly more compressed. Ostium and cauda are less clearly differentiated, almost completely fused. Atherestes JORDAN & GILBERT 1881 Type-species: Platisomatichthys stomias JORDAN & GILBERT 1881 Species and distribution: Two species – A. stomias from the Pacific coast of North America, from the Bering Sea to San Francisco, and A. evermanni from Japan. Diagnosis: Thin, moderately elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with postdorsal and somewhat more prominent predorsal angle, sometimes finely crenulated, posterior tip blunt to irregularly rounded, anterior tip projecting like a rostrum, rounded. Index l:h 1.5 to 1.9. Otolith size at least 9 mm. Otoliths below a size of 6.5 mm may not have developed all pertinent diagnostic features. Ostium wider than cauda and much longer. Index ol:cl 1.6 to 2.2. Ostial opening strongly reduced. Cauda short, with rounded termination at considerable distance from the posterior rim of the otolith. Sulcus well divided into ostium and cauda, its respective colliculi deepened (only in otoliths of the blind, left side). Circumsulcal depression completely connected, wide and rather deep. Inner face almost completely flat and rather smooth; outer face also practically flat, with little ornamentation. Rims sharp, ventrally smooth, dorsally and posteriorly sometimes finely crenulated. Measurements: stomias (left) stomias (right) evermanni (left) evermanni (right) l:h 1.60-1.90 1.50-1.60 1.50-1.65 1.50 h:t 4.5 nm 4.5 nm ol:cl 1.60-2.00 1.75-2.25 2.2 2.2 oh:ch con.i 1.3-1.4 nm 1.1-1.2 nm 1.2-1.5 nm 1.25 nm Ontogeny and variability: Smaller specimens below 6.5 to 7 mm length are more rounded in outline and the otolith rims are more densely crenulated. Variability on the other hand seems to be restricted to very minor details only. Discussion: Otoliths of the genus Atherestes probably show the most elongate otoliths in this group with the least side dimorphism. Atherestes stomias (JORDAN & GILBERT 1881) Figs. 493-497 Investigated otoliths: 6 otoliths (left and right) from off California, ZMH Ot. 21.1.1995.9-14 (leg. Fitch). Discussion: Otoliths of A. stomias do not differ greatly from those of A. evermanni. They are slightly more elongate and the proportions of the sulcus are slightly different. Distribution: North America, Bering Sea to San Francisco, fossil from the Pleistocene of California. Atherestes evermanni JORDAN & STARKS 1904 Figs. 498-500 Investigated otoliths: 3 otoliths (2 left side and 1 right side) from Japan, ZMH Ot. 21.1.1995.1516 (leg. BMNH 1923.9.28.2-4) and BMNH 1923.9.28.2-4. Discussion: See entry to A. stomias. Distribution: Japan. Piscium Catalogus, Part Otolithi piscium, Vol. 2 216 493a 494 493c 493b 495 497 496 499 498a 498c 498b 500 Figs. 493-497: Atherestes stomias (JORDAN & GILBERT 1881) – 6 × Figs. 498-500: Atherestes evermanni JORDAN & STARKS 1904 – 6 × Cleisthenes JORDAN & STARKS 1904 Type-species: Cleisthenes pimetorum JORDAN & STARKS 1904 syn. Protopsetta Jordan & STARKS 1906 (typespecies: Hippoglossoides herzensteini) Diagnosis: Thin, rather compressed otoliths; ventral rim deeply and gently curving, deepest at about the middle, dorsal rim with prominent and somewhat projecting postdorsal and predorsal angles, faintly undulating, posterior tip blunt, ventrally rounded, dorsally concave, anterior tip slightly projecting like a rostrum, rounded. Index l:h 1.25 to 1.4. Otolith size at least 7 mm. Ostium wider than cauda and much longer. Index ol:cl 1.6 to 2.0. Ostial opening strongly reduced. Cauda short, with rounded termination at considerable distance from the posterior rim of the otolith. Colliculi well separated and somewhat deepened. Circumsulcal depression completely connected and rather wide. Inner face almost entirely flat, smooth; outer face flat, rather smooth. Rims sharp. Schwarzhans: Pleuronectiformes 217 501c 502 501a 501b 504 503 Figs. 501-504: Cleisthenes herzensteini (SCHMIDT 1904) – 6 × Measurements: herzensteini l:h 1.25-140 h:t 4.5 ol:cl oh:ch 1.70-2.00 1.25-1.45 con.i nm Side dimorphism: Rather inconspicuous. Otoliths of the eyed side show a less pronounced predorsal angle, and ostium and cauda are less clearly differentiated. Variability: Variability of otoliths of this genus is very low, restricted to details of the marginal ornamentation. Discussion: Otoliths of the genus Cleisthenes resemble those of Atherestes, but are more compressed and show a very typical development of the dorsal rim Species and distribution: Two species (sometimes regarded as subspecies of a single species only) – C. herzensteini from the Okhotsk Sea to Japan, Korea and northern China and C. pimetorum from Japan. Cleisthenes herzensteini (SCHMIDT 1904) Figs. 501-504 Investigated otoliths: 4 otoliths (3 left side and 1 right side) from Toyama, Japan, ZMH Ot. 22.1.1995.1-3 (leg BMNH 1933.6.12.7 and BMNH 1931.9.18.9-10) and BMNH 1931.9.18.9-10. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Okhotsk Sea, Japan, Korea and northern China. Lyopsetta JORDAN & GOSS 1887 Type-species: Hippoglossoides exilis JORDAN & GILBERT 1887 Diagnosis: Moderately thin and moderately elongate otoliths; ventral rim rather shallow, irregularly curving, deepest somewhat behind the middle, dorsal rim with postdorsal angle, slightly undulating, posteriorly irregularly rounded, anterior tip projecting like a rostrum, rounded. Index l:h 1.3 to 1.5. Otolith size at least 5 mm. The critical diagnostic size is reached with about 3.5 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 1.7 to 2.0. Ostial opening strongly reduced. Cauda short, with rounded termination at great distance from the posterior rim of the otolith. Ostial and caudal colliculi well separated and deepened. Sulcus relatively wide. Circumsulcal depression well developed and rather wide and deep. Inner face almost completely flat and rather smooth; outer face slightly convex and smooth. Rims sharp. Measurements: exilis l:h 1.30-1.50 h:t 3.0 ol:cl 1.70-2.00 oh:ch 1.0-1.2 con.i nm 218 506a 505c 505a 506b 505b 508 507 509 510 Figs. 505-510: Lyopsetta exilis JORDAN & GILBERT 1881) – 10 × Side dimorphism: Side dimorphism in otoliths of this genus again is not very strongly developed. Otoliths of the eyed side almost completely lack the differentiation of ostial and caudal colliculi and the ostium is narrower, about the width of the cauda only. Right hand otoliths are more convex in the vertical direction. Ontogeny and variability: Otoliths below 3.5 mm are more compressed and rounded in outline and show slightly more intense marginal crenulation, thus not exhibiting all the pertinent diagnostically important features. Variability on the other hand is low and restricted to details of the outline and the proportions. Discussion: Otoliths of the genus Lyopsetta are very similar to those of the genera Hippoglossoides and Acanthopsetta. Especially differentiation from Hippoglossoides is very feeble and judging from otolith morphology alone may not warrant separation of the two genera. Species and distribution: Lyopsetta is a monospecific genus with L. exilis restricted to the deeper water of the Pacific coast of North America. Lyopsetta exilis (JORDAN & GILBERT 1881) Figs. 505-510 Investigated otoliths: 6 otoliths (left and right side) from off California, ZMH Ot. 22.1.1995.4-9 (leg. Fitch). Distribution: Pacific coast of North America, from Alaska to San Francisco in rather deep water; fossil from the Upper Pliocene and Pleistocene of California. Schwarzhans: Pleuronectiformes 219 a c b Fig. 511: Acanthopsetta nadeshnyi SCHMIDT 1904 – 10 × Acanthopsetta SCHMIDT 1904 Type-species: Acanthopsetta nadeshnyi SCHMIDT 1904 Diagnosis: Thin, moderately elongate otoliths; ventral rim shallow, gently curving, deepest behind the middle, dorsal rim with rounded postdorsal angle, otherwise smooth and gently curving, posterior tip blunt, projecting strongest ventrally and with notch towards the postdorsal angle, anterior tip projecting like a rostrum, rounded. Index l:h about 1.4. Otolith size at least 6 mm. Ostium slightly wider than cauda and somewhat longer. Index ol:cl 1.3. Ostial opening strongly reduced. Cauda short, with rounded termination at considerable distance from the posterior rim of the otolith. Colliculi well separated and rather strongly deepened. Circumsulcal depression completely connected, rather deep and extremely wide, reaching close to the margins of the otolith. Inner face almost completely flat and rather smooth; outer face slightly convex and smooth. Rims sharp. Measurements: nadeshnyi l:h 1.40 h:t 3.1 ol:cl 1.30 oh:ch 1.25 con.i nm Side dimorphism: No data. Discussion: Otoliths of the genus Acanthopsetta closely resemble those of the genera Hippoglossoides and Lyopsetta but differ in the development of the posterior rim. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Species and distribution: Acanthopsetta is a monospecific genus with A. nadeshnyi known from the Okhotsk Sea to Japan and Korea. Acanthopsetta nadeshnyi SCHMIDT 1904 Fig. 511 Investigated otoliths: 1 otolith (left side) from Petropavlovsk, Kamchatka, BMNH 1923.11.21.6. Distribution: Sea of Okhotsk to Japan and Korea. Hippoglossoides GOTTSCHE 1835 Type-species: Hippoglossoides limanda GOTTSCHE 1835 (H. platessoides limandoides) syn. Drepanopsetta GILL 1861 (type-species: Pleuronectes platessoides platessoides) syn. Pomatopsetta GILL 1864 (type-species: Platessa dentata, syn. H. platessoides platessoides) syn. Cynopsetta JORDAN & STARKS 1906 (typespecies: Hippoglossoides dubius) Diagnosis: Thin, roundish to moderately elongate otoliths; ventral rim moderately deep, gently curving, deepest at or slightly behind the middle, dorsal rim with postdorsal angle, somewhat undulating, posterior tip blunt, sometimes slightly projecting ventrally, often irregularly undulating, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.25 to 1.5. Otolith size at least 9 mm. Otoliths smaller than 4 mm may not have developed all pertinent diagnostic features. 220 Ostium wider than cauda and much longer. Index ol:cl 1.9 to 2.2. Ostial opening strongly reduced. Cauda short, with rounded termination at considerable distance from the posterior rim of the otolith. Sulcus very short, relatively wide. Colliculi clearly separated and considerably deepened. Circumsulcal depression completely connected, moderately deep and very wide. Inner face almost completely flat and rather smooth; outer face slightly convex and smooth too. Rims sharp. tic, and H. elassodon, H. dubius and H. robustus in the North Pacific. Measurements: Investigated otoliths: 4 otoliths (left and right) from the North Sea, ZMH Ot. 22.1.1995.10-13 (coll. Schwarzhans). platessoides elassodon dubius (left) dubius (right) l:h 1.30-1.40 1.35-1.50 1.25-1.35 1.20 h:t 3.3 4.0 3.2 4.0 ol:cl 2.00-2.20 2.00-2.20 1.9-2.2 (2.5) oh:ch 1.1-1.3 1.1-1.5 1.5-1.8 1.1 con.i nm nm nm nm Side dimorphism: In H. platessoides and H. elassodon side dimorphism of the otoliths is rather inconspicuous. The only obvious dimorphism is the fact that otoliths of the eyed side show a less clear separation of ostium and cauda and a somewhat more narrow sulcus. In H. dubius these two characters are developed much more dimorphous. In addition, the shape of the otolith of the eyed side is more roundish and the anterior-ventral rim shows an intense crenulation. This kind of dimorphism resembles the extreme side dimorphism observed in the otoliths of the genus Reinhardtius (see respective entry). Ontogeny and variability: Otoliths smaller than 4 mm tend to be more roundish and less characteristic. Variability is moderate, mainly restricted to variations in the expression of dorsal and posterior rims and some of the otolith and sulcus proportions. Discussion: Otoliths of the genus Hippoglossoides closely resemble those of the related genera Acanthopsetta and Lyopsetta, and it must be doubted whether the few differences observed in otolith morphology are stable enough to support their separation in three different genera. The aberrant otoliths of Reinhardtius also resemble to a certain extent, in particular the otoliths of H. dubius (for detailed discussion see entry to Reinhardtius). Species and distribution: Four species and two subspecies – H. platessoides from the North Atlantic, with one subspecies along the North American shores and another in the North-East Atlan- Hippoglossoides platessoides FABRICIUS 1780 Figs. 512-515 syn. Pleuronectes limandoides BLOCH 1787 [subspecies] syn. Hippoglossoides limanda GOTTSCHE 1835 syn. Hippoglossoides dentatus STORER 1839 Discussion: Very similar to H. elassodon from the North Pacific but slightly more compressed and with a more massive anterior tip. Distribution: Two subspecies – H. p. platessoides (FABRICIUS 1780) from the northern Atlantic coast of the USA and H. p. limandoides (BLOCH 1787) from the coasts of north-western Europe. The investigated specimens from the North Sea belong to the latter subspecies. Also known as fossil from the Pleistocene of Belgium. Hippoglossoides elassodon JORDAN & GILBERT 1881 Figs. 516-519 Investigated otoliths: 4 otoliths (left and right) from Alaska, ZMH Ot. 22.1.1995.14-17 (leg. Fitch). Discussion: Closely related to H. platessoides (see respective entry). Distribution: Northern Pacific coast of North America and Sea of Okhotsk. Hippoglossoides dubius SCHMIDT 1904 Figs. 520-523 syn. Hippoglossoides katakurae SNYDER 1911 Investigated otoliths: 4 otoliths, 2 (left and right, figs. 520-521) from Wakkanai, Hokkaido, Japan, coll. Ohe No. 811212, and 2 (left and right, figs. 522-523) from Owase, Mie prefecture, Japan, coll. Ohe No. 760828. Schwarzhans: Pleuronectiformes 221 514 512a 512c 513 512b 515 518 516a 516c 516b 517 519 Figs. 512-515: Hippoglossoides platessoides FABRICIUS 1780 – 6 × Figs. 516-519: Hippoglossoides elassodon JORDAN & GILBERT 1881 – 6 × Discussion: Otoliths of this species are remarkable for their strong side dimorphism. Left otoliths (from the blind side) show a more elongate outline, a much wider sulcus and a clear separation of the two colliculi. Also the sulcus is extremely short. Distribution: Southern Okhotsk Sea to Japan and Korea. Reinhardtius GILL 1861 Type-species: Pleuronectes cynoglossus sensu FABRICIUS 1780 (syn. R. hippoglossoides) syn. Platysomatichthys BLEEKER 1862 (type-species: Pleuronectes pinguis, syn. R. hippoglossoides) Remarks: Otoliths of the genus Rheinhardtius are probably the ones with the most drastic side dimorphism. This necessitates a separate description of left (blind side) and right (eyed side) specPiscium Catalogus, Part Otolithi piscium, Vol. 2 imens (replacing the chapter on side dimorphism). Amazingly, Reinhardtius is one of two flatfishes known to be swimming in an upright position (the other one being the “primitive” Psettodes). In the case of Reinhardtius this is clearly an adaption to its role as an active predator in the open sea. Why this way of living has resulted in such an extreme development of side dimorphism in otoliths at this stage remains unresolved. Diagnosis (left, blind side): Very thin, moderately elongate otoliths; ventral rim deeply curving, with pronounced midventral angle, dorsal rim with pronounced postdorsal and slightly less pronounced predorsal angle, intensely furcate, posterior rim blunt, nearly vertically cut, with deeply serrated ornamentation, sometimes developed to form fenestrae, anterior tip strongly projecting like a rostrum, not much rounded. Index l:h 1.4 to 1.5. Otolith size at least 15 mm. Ostium very much wider than cauda and much longer, too. Index ol:cl about 3.0. Ostial opening reduced. Cauda extremely short, round- 222 520a 521a 520b 521b 520c 521c 522a 523 522b Figs. 520-523: Hippoglossoides dubius SCHMIDT 1904 – 6 × ish, terminating very far from the posterior rim of the otolith. Sulcus shallow, except for a small portion in the rear area of the ostium, which is slightly deepened. Circumsulcal depression well developed, very wide and somewhat deepened. Inner face completely flat, even slightly concave in cases, showing some concentrical growth furrows in the circumslucal depression and dorsally and posteriorly some radial furrows originating from the marginal ornamentation; outer face flat, with some radial furrows. Rims sharp. (Right, eyed side): Very thin, rather compressed otoliths; ventral rim deeply and regularly curving, deepest at about the middle, anterior-ventral portion strongly serrated, sometimes with development of fenestrae, dorsal rim with equally pronounced pre- and postdorsal angles, smooth, posterior rim blunt or broadly rounded, smooth, anterior tip strongly projecting like a rostrum, rounded. Index l:h 1.25 to 1.35. Otolith size at least 15 mm. Ostium and cauda practically completely fused, including the colliculi, which anteriorly are elevated and posteriorly somewhat deepened. Sulcus as a whole rather narrow, long, and except for the colliculi very poorly defined. Ostial opening reduced, but reaching relatively close to the anterior rim of the otolith. Cauda terminating not very far from the posterior rim of the otolith. Circumsulcal depression well developed only in the posterior portion, there very wide and somewhat deepened. Inner face flat, but with ventral portion somewhat bent outward, smooth except for few radial furrows originating from the marginal ornamentation; outer face flat to slightly concave, with some radial furrows. Rims sharp. Measurements: l:h h:t hippoglossoides (l.)1.40-1.50 5.5 hippoglossoides (r.)1.25-1.35 5.5 ol:cl oh:ch about 3.0 about 3.0 nm nm con.i nm nm Schwarzhans: Pleuronectiformes 223 Side dimorphism: See above (diagnosis and remarks). 7.7.3 Glyptocephalus Group Genera: Two genera – Tanakius and Glyptocephalus. Variability: Overall variability is moderate. The intensity of the ornamentation of the rims of the otoliths and the development of “fenestrae” are apt to some variations Discussion: NORMAN (1934) related Reinhardtius to Atherestes. Otoliths of the “less altered” blind side indeed suggest a relationship of Reinhardtius to the genera of the Hippoglossoides Group, in which I have also placed Atherestes. The high degree of otolith specialization, however, hampers any detailed interpretation. Nevertheless, it seems that in certain species of the genus Hippoglossoides (H. dubius, see respective entry) the kind of extreme side dimorphism of otoliths found in Reinhardtius is “foreshadowed” to a certain degree. I therefore tend to relate Reinhardtius closer to Hippoglossoides than to Atherestes. Species and distribution: Reinhardtius is a monospecific genus with R. hippoglossoides occurring pelagically in the Northern Atlantic and the Northern Pacific. Specimens caught in the Northern Pacific have originally been described as a distinct species (R. matsuurae), but NORMAN (1934) already suggested them to represent an identical species. Otoliths available from fishes of both regions clearly support his view. Reinhardtius hippoglossoides (WALBAUM 1792) Figs. 524-528, 20 syn. Pleuronectes cynoglossus (non LINNAEUS) sensu FABRICIUS 1780 syn. Pleuronectes pinguis FABRICIUS 1824 syn. Reinhardtius matsuurae JORDAN & SNYDER 1901 Investigated otoliths: 5 otoliths, 2 (left and right, figs. 526-527) from off Hokkaido, Japan, IRSNB (coll. Nolf), 1 (left, fig. 528) from of New Foundland, IRSNB (coll. Nolf), 2 (right, fig. 524-525) from off Greenland, ZMH Ot. 22.1.1995.18-19 (leg. Fitch). Distribution: Pelagic in deeper waters of the northern North Atlantic and the North Pacific. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Definition and relationship: The Glyptocephalus Group no doubt is closely related to the preceding Hippoglossoides Group and probably represents a specialized offshot from it. Its otoliths merely differ from those of the Hippoglossoides Group in its more gently curving outline and the more compressed appearance (particularly the genus Glyptocephalus). NORMAN (1934) related them instead to Limanda and related genera (e.g. Dexistes) based on the small and asymmetrical mouth which they share with these genera and which he used as one of the main features for grouping the various genera in his Pleuronectinae (see general discussion to Pleuronectidae). In this particular case, this characterization does not seem to hold and otoliths clearly point to a closer relationship with the Hippoglossoides Group. Tanakius HUBBS 1918 Type-species: Microstomus kitaharae JORDAN & STARKS 1904 Diagnosis: Moderately thin, ovale otoliths; ventral and dorsal rims shallow and gently curving, without prominent angles or ornamentation, posterior and anterior rims broadly rounded. Index l:h 1.6. Otolith size at least 4 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 2.0. Ostial opening reduced. Colliculi well separated and deepened. Cauda short, round, terminating at some distance from the posterior rim of the otolith. Sulcus rather wide, moderately short. Circumsulcal depression well developed, wide and somewhat deepened. Inner face flat, smooth; outer face slightly convex and smooth. Rims sharp. Measurements: kitaharae l:h 1.60 h:t 3.2 ol:cl 2.00 oh:ch 1.2 con.i 4 Side dimorphism: No data. Discussion: Otoliths of the genus Tanakius are readily distinguished of those of the related genus Glyptocephalus in being more elongate. They probably represent the more plesiomorphic character status. 224 524a 525 524c 524b 527a 526 527b 527c 528a 528c 528b Figs. 524-528: Reinhardtius hippoglossoides (WALBAUM 1792) – 6 × Species and distribution: Tanakius is a monospecific genus with T. kitaharae restricted to the waters of Japan and Korea. Tanakius kitaharae JORDAN & STARKS 1904 Fig. 529 Investigated otoliths: 1 otolith (left side) from Japan, BMNH 1923.11.21.19. Distribution: Southern Japan and Korea. Schwarzhans: Pleuronectiformes 225 Glyptocephalus GOTTSCHE 1835 Type-species: Pleuronectes saxicola FABER 1828 (syn. G. cynoglossus) syn. Errex JORDAN 1919 (type-species: Glyptocephalus zachirus) Diagnosis: Moderately thin, almost perfectly round otoliths; all rims gently curving, sometimes slightly undulating, otherwise smooth, postdorsal and sometimes also predorsal angle weekly developed. Index l:h 1.0 to 1.25. Otolith size at least 8 mm, but otoliths of about 4.5 mm already diagnostically mature. Ostium wider than cauda and somewhat longer. Index ol:cl 1.4 to 1.6. Ostial opening reduced. Cauda short, round, terminating at some distance from the posterior rim of the otolith. Colliculi well separated and deepened. Sulcus moderately wide and short. Circumsulcal depression well developed, wide, but not very deep.. Inner face practically flat, smooth, except for few thin radial furrows to be seen within the circumsulcal depression; outer face slightly convex, rather smooth. Rims sharp. a b Fig. 529: Tanakius kitaharae JORDAN & STARKS 1904 – 10 × Discussion: Otoliths of the genus Glyptocephalus are readily recognized by their compressed, roundish outline. Species and distribution: Three species from the North Atlantic and North Pacific – G. cynoglossus, G. zachirus and G. stelleri. Glyptocephalus cynoglossus (LINNAEUS 1758) Figs. 530-531 Measurements: cynoglossus zachirus l:h 1.00 1.10-1.25 h:t 4.0 3.3 ol:cl 1.5 1.4-1.5 oh:ch 1.2 1.1-1.4 con.o 3.2 2.8 Side dimorphism: Side dimorphism in otoliths of the genus Glyptocephalus is quite strongly developed. First of all, otoliths of the eyed side differ from those of the blind side in the completely fused colliculi (intrasulcal proportions listed above therefore are only valid for left hand otoliths). The sulcus is also narrower in otoliths from the eyed side and within the circumsulcal depression radial furrows are much more common. Also the rear part of the circumsulcal depression is more deepened, sometimes showing concentric growth lines. Ontogeny and variability: A single large specimen obtained from G. zachirus does not differ greatly from the smaller ones, except for being slightly more elongate and showing a more rounded outline than smaller specimens of the same species. Likewise, variability seems to be restricted to minor variations of the outline. Piscium Catalogus, Part Otolithi piscium, Vol. 2 syn. syn. syn. syn. Pleuronectes saxicola FABER 1828 Pleuronectes nigromanus NILSSON 1829 Platessa elongata YARELL 1839 Glyptocephalus acadianus GILL 1873 Investigated otoliths: 2 otoliths (left and right) from the North Atlantic, Meteor St. 2017, ZMH Ot. 23.1.1995.1-2 (leg. W. Schmidt). Discussion: Although otoliths of the Glyptocephalus species do not differ much from each other, those of G. cynoglossus may be recognized as the most compressed ones. Distribution: On both sides of the North Atlantic. Glyptocephalus zachirus LOCKINGTON 1878 Figs. 532-538, 22 Investigated otoliths: 5 otoliths (2 left and 3 right, figs. 532-536) from off California, ZMH Ot. 23.1.1995.3-7 (leg. Fitch), and 2 otoliths (left and right, figs. 537-538) as G. aff. zachirus (identified 226 530a 530c 531 530b 532a 532b 533 532c 534 535 536 Figs. 530-531: Glyptocephalus cynoglossus (LINNAEUS 1758) – 6 × Figs. 532-536: Glyptocephalus zachirus LOCKINGTON 1878 – 6 × as Brachypleura novaezeelandiae probably due to mistake in jar labels) from the ZMH collection, ZMH 20010. Discussion: Otoliths of G. zachirus are slightly more elongate than those of G. cynoglossus. Distribution: Pacific coast of North America, from the Bering Sea to San Francisco; fossil from the Pleistocene of California. 7.7.4 Pleuronectes-Limanda Group Genera: 9 genera – Limanda, Dexistes, Liopsetta, Parophrys, Pleuronectes, Platichthys, Kareius, Pseudopleuronectes, Lepidopsetta and Inopsetta – distributed in the northern Atlantic and the northern Pacific. Definition and relationship: This group combines the bulk of the genera placed by NORMAN (1934) in the category of Pleuronectinae with a small and asymmetrical mouth. Their otoliths are typically elongate and thin to very thin, usually with a pronounced postdorsal angle and a very smooth inner face. The sulcus is relatively long and shallow. The ostial opening is quite reduced. The cauda is much shorter than the ostium and terminates at considerable distance from the posterior rim of the otolith. Although forming a dense unit in respect to the otolith morphology this group could be subdivided into two smaller subgroups. One subgroup would cluster around Limanda (including Dexistes and Liopsetta). These otoliths are more gently curving in outline and their sulcus is more structured. In this respect they show a certain resemblance to otoliths of the Hippoglossoides and Schwarzhans: Pleuronectiformes 227 even the Glyptocephalus Groups. All the other genera clustering around Pleuronectes seem to be very closely related to each other and distinction of the genera by means of otoliths is not always easy. They show better resemblance to the Hippoglossus Group (in particular the genus Eopsetta). I assume the Pleuronectes-Limanda Group to be basically related to the Hippoglossus and may be also the Hippoglossoides Group. 538 537a 537b Limanda GOTTSCHE 1835 Type-species: Pleuronectes limanda LINNAEUS 1758 syn. Myzopsetta GILL 1864 (type-species: Platessa ferruginea STORER 1839) Diagnosis: Thin, moderately elongate to roundish otoliths; ventral rim gently curving, deepest at about the middle, dorsal rim with rounded postdorsal angle, often somewhat undulating, posterior tip blunt to irregularly rounded, anterior tip slightly projecting like a rostrum, rounded. Index l:h 1.25 to 1.6. Otolith size at least 5 mm. Diagnostic size reached at about 3 to 3.5 mm. Ostium not much wider than cauda, but considerably longer. Index ol:cl 1.9 to 2.4. Ostial opening reduced. Cauda short, rounded, terminating at some distance from the posterior rim of the otolith. Sulcus relatively shallow. Circumsulcal depression completely connected and wide, but rather shallow. Inner face rather flat and smooth; outer face completely flat, smooth or faintly ornamented. Rims sharp. Measurements: Figs. 537-538: Glyptocephalus aff. zachirus LOCKINGTON 1878 – 6 × Discussion: Otoliths of Limanda show the closest resemblance to those of Dexistes, the latter merely differing in a more elongate shape, an almost completely flat inner face and a somewhat deeper sulcus. Species and distribution: 6 recent species – L. limanda and L. ferruginea from the North Atlantic, and L. aspera, L. punctatissima, L. proboscidea and L. sakhalinensis from the North Pacific. Limanda is also one of the very few Pleuronectid genera known from a fossil otolith based species – L. ignobilis from the Upper Oligocene of northern Germany. Limanda limanda (LINNAEUS 1758) Figs. 539-541 syn. Pleuronectes limandula BONATERRE 1788 syn. Limanda vulgaris GOTTSCHE 1835 syn. Limanda oceanica BONAPARTE 1846 con.i about 9 about 5 3.5 about 5 Investigated otoliths: 3 otoliths, 2 (right side, figs.) form the North Sea, ZMH Ot. 23.1.1995.8-9 (coll. Schwarzhans) and 1 (left side, fig. ) (as L. ferruginea) from Iceland, ZMH Ot. 23.1.1995.10 (leg. ZMUC 853359-61). Side dimorphism: Side dimorphism in the species of the genus Limanda is only feeble. Otoliths of the eyed side show a slightly stronger postdorsal angle and the colliculi are less well separated. Discussion: Of all the species investigated from this genus the otoliths of L. limanda are the most elongate. limanda aspera ferruginea †ignobilis l:h 1.50-1.60 1.30-1.40 1.25-1.30 1.40 h:t 4.0 3.2 3.8 4.2 ol:cl 1.90-2.25 2.0-2.4 2.3-2.6 2.1 oh:ch 1.0-1.2 1.1-1.3 1.1-1.2 1.2 Ontogeny: Smaller specimens, particularly below 3.5 to 3 mm are somewhat more gently rounded in outline and its rims are much more intensely crenulated. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Coasts of north-western Europe and Iceland; fossil from the Pleistocene of Belgium and southern England. 228 540 539a 539c 541 539b Figs. 539-541: Limanda limanda (LINNAEUS 1758) – 10 × Limanda aspera (PALLAS 1814) Figs. 542-544 syn. Limanda asprella HUBBS 1915 Investigated otoliths: 3 otoliths (1 left and 2 right) from the Bering Sea, ZMH Ot. 23.1.1995.11-13 (leg. Fitch). Limanda ignobilis SCHWARZHANS 1994 Fig. 549 Investigated otoliths: The unique holotype from the uppermost Oligocene (Chatt C) of Krefeld, northern Germany, GPIM-M 2916 (leg. von der Hocht). Discussion: Otoliths of L. aspera are more compressed than those of L. limanda, but less than those of L. ferruginea. Discussion: This fossil species differs from the recent ones mainly in the longer sulcus which reaches somewhat closer to the anterior tip of the otolith. Distribution: Bering Sea to Vancouver Island and Korea. Distribution: Upper Oligocene of northern Germany. Limanda ferruginea (STORER 1839) Figs. 545-548 Dexistes JORDAN & STARK 1904 Type-species: Dexistes rikuzenius JORDAN & STARKS 1904 syn. Myzopsetta rostrata GILL 1861 Investigated otoliths: 4 otoliths (left and right) from Iceland, ZMH Ot. 23.1.1995. 14-17 (leg. ZMUC 853359-61). Discussion: L. ferruginea shows the most compressed otoliths within this genus, and with the smallest cauda. Otolith margins are relatively intensely crenulated. Distribution: Atlantic coast of North America, from Labrador to New York, and eastward to Iceland. syn. Araias JORDAN & STARKS 1904 (type-species: A. ariommus, syn. D. rikuzenius) Diagnosis: Moderately thin and rather elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim without prominent postdorsal angle, but rounded predorsal projection, slightly undulating, posterior tip rounded, anterior tip slightly projecting like a rostrum, rounded. Index l:h 1.7 to 1.8. Otolith size at least 6 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 1.9 to 2.0. Ostial opening reduced. Cauda short, with rounded termination at some distance from the posterior rim of the Schwarzhans: Pleuronectiformes 229 542 544a 543 544b 546 545a 545c 545b 547 548 Figs. 542-544: Limanda aspera (PALLAS 1814) – 10 × Figs. 545-548: Limanda ferruginea (STORER 1839) – 10 × otolith. Colliculi separated, sulcus slightly deepened. Circumsulcal depression well developed, wide and somewhat deepened. Inner face completely flat, smooth; outer face slightly convex and smooth. Rims sharp. Measurements: rikuzenius l:h 1.70-1.80 h:t 2.7 ol:cl oh:ch 1.90-2.00 1.05-1.3 a con.o 3.4 c Side dimorphism: No data. Discussion: Very similar to Limanda (see respective entry). b Fig. 549: Limanda ignobilis SCHWARZHANS 1994 – 15 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 230 550a 550c 551 550b Figs. 550-551: Dexistes rikuzenius JORDAN & STARKS 1904 – 10 × Species and distribution: Dexistes is a monospecific genus with D. rikuzenius known from the shores of Japan. Dexistes rikuzenius JORDAN & STARKS 1904 Figs. 550-551 syn. Araias ariommus JORDAN & STARKS 1904 Investigated otoliths: 2 otoliths (left side) from Japan, ZMH Ot. 23.1.1995.18 (leg. BMNH 1933.6.12.14) and BMNH 1933.6.12.14. Distribution: Coasts of Japan. cauda and longer. Index ol:cl 1.3 to 1.6. Ostial opening reduced. Cauda short, roundish, terminating at some distance from the posterior rim of the otolith. Colliculi well separated, sulcus somewhat deepened. Circumsulcal depression completely connected, rather narrow and not very deep. Inner face flat, not very smooth. Rims moderately sharp. Measurements: putnami glacialis obscurus l:h 1.55 1.60 1.75 h:t 3.4 3.6 3.0 ol:cl oh:ch con.i 1.60 1.75 nm 1.40-1.60 1.15-1.45 about 7 1.30 1.20 about 5 Side dimorphism: No data. Liopsetta GILL 1864 Type-species: Platessa glabra (non RATHKE) sensu STORER 1844, syn. L. putnami syn. Euchalarodus GILL 1864 (type-species: Pleuronectes obscurus) Diagnosis: Moderately thin and moderately elongate otoliths; ventral rim very shallow, gently curving, deepest at about the middle, dorsal rim with postdorsal angle, slightly undulating, posterior tip blunt, with somewhat projecting posterior-ventral corner, anterior tip blunt, with faint rostrum like projection. Index l:h 1.55 to 1.75. Otolith size at least 6 mm. Ostium slightly to considerably wider than Variability: The two specimens of L. glacialis already indicate, that the variability in the species of this genus probably is more considerable than in other genera of the Pleuronectes-Limanda Group. It concerns the expression of the posterior tip of the otolith and proportions of the sulcus. Discussion: The posterior-ventrally projecting posterior rim in combination with the somewhat deepened sulcus characterize otoliths of this genus. Species and distribution: Four species – L. obscura and L. pinnifasciata from the North Pacific, L. putnami from the Atlantic coast of North America, and L. glacialis from the Arctic coasts of Siberia and Alaska. Schwarzhans: Pleuronectiformes 231 553 552a 552c 552b 555a 555b 554a 554b Figs. 552-553: Liopsetta glacialis (PALLAS 1776) – 10 × Fig. 554: Liopsetta putnami (GILL 1864) – 10 × Fig. 555: Liopsetta obscura (HERZENSTEIN 1891) – 10 × Liopsetta putnami (GILL 1864) Fig. 554 syn. Platessa glabra (non RATHKE) sensu STORER 1844 Investigated otoliths: 1 otolith (left side) from off Massachusetts, USA, BMNH 1924.2.25.1. Investigated otoliths: 2 otoliths (left side) from off northern Alaska, ZMH Ot. 23.1.1995.19 (leg. BMNH 1932.12.31.35-36) and BMNH 1932.12.31. 35-36. Discussion: Similar to L. putnami, but with less widened ostium. Distribution: Arctic coasts of Siberia and Alaska. Discussion: The otoliths of L. putnami are readily recognized by their much widened ostium and the more rounded dorsal rim. Distribution: Atlantic coast of North America, from Labrador to Cape Cod. Liopsetta glacialis (PALLAS 1776) Figs. 552-553 syn. Pleuronectes cicatricosus PALLAS 1814 syn. Platessa dwinensis LILLJEBORG 1851 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Liopsetta obscurus (HERZENSTEIN 1891) Fig. 555 Investigated otoliths: 1 otolith (left side) from off Vladivostock, Russia, BMNH 1923.12.18.6-7. Discussion: Otoliths of L. obscura are considerably more elongate than those of the two other species of the genus investigated. Distribution: Okhotsk Sea, Sakhalin Island, Sea of Japan, and Yellow Sea. 232 Parophrys vetula GIRARD 1856 Figs. 556-560, 19 Parophrys GIRARD 1856 Type-species: Parophrys vetula GIRARD 1856 Diagnosis: Thin, elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with postdorsal angle, somewhat undulating, posterior tip blunt, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.65 to 2.0. Otolith size at least 10 mm. Otoliths below 5 mm not diagnostically mature. Ostium slightly wider than cauda and much longer. Index ol:cl 2.15 to 2.65. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi separated. Circumsulcal depression well developed, wide, slightly deepened. Inner face rather flat and smooth; outer face also flat and smooth. Rims sharp. (left, adult) (right, adult) (left, juv.) (right, juv.) Investigated otoliths: 5 otoliths (2 left and 3 right) from off California, ZMH Ot. 24.1.1995.1-5 (leg. Fitch). Distribution: Pacific coast of North America, from Sitka to Santa Barbara; fossil from the Pleistocene of California. Pleuronectes LINNAEUS 1758 Type-species: Pleuronectes platessa LINNAEUS 1758 syn. Platessa CUVIER 1817 (type-species: Pleuronectes platessa) Measurements: vetula vetula vetula vetula syn. Pleuronectes diagrammus GÜNTHER 1862 syn. Parophrys hubbardi GILL 1863 l:h 2.00 1.70 1.70 1.65 h:t 3.5 3.8 3.2 3.3 ol:cl 2.65 2.50 2.25 2.25 oh:ch 1.6 1.35 1.15 1.20 con.i about 10 about 10 about 7 about 5 Side dimorphism: Side dimorphism in this genus is moderate. It so seems that otoliths of the eyed (right) side are somewhat more compressed and show less well separated colliculi in the sulcus. In the vertical direction the inner face of otoliths of the eyed side is slightly more convex and the area of the circumsulcal depression often shows delicate radial furrows and concentrical growth rings. Ontogeny: Small specimens, particularly below 5 mm, are somewhat more compressed and a show a more intense crenulation of the otolith rims. Discussion: Otoliths of the genus Parophrys resemble those of Eopsetta from the Hippoglossus Group in general appearance. In fact, this could point to a possible relationship. Genera of the Pleuronectes-Limanda Group differ mainly in being less elongate. Species and distribution: Parophrys is a monospecific genus with P. vetula restricted to the Pacific coast of North America. Diagnosis: Thin, moderately elongate, ovale otoliths; ventral rim shallow, gently curving, deepest at about the middle, often delicately crenulated, dorsal rim with sharp postdorsal angle, somewhat undulating, posterior tip blunt, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.45 to 1.6. Otolith size at least 7 mm. Otoliths below 3 to 4 mm not diagnostically mature. Ostium slightly wider than cauda and much longer. Index ol:cl 1.5 to 2.1. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Colliculi separated, but not very clearly though. Cauda slightly deepened and also the anterior portion of the ostium. Circumsulcal depression well developed, not very wide, rather shallow. Inner face slightly convex, rather smooth; outer face flat and delicately ornamented. Rims sharp. Measurements: platessa l:h h:t ol:cl oh:ch 1.45-16.0 4.0-5.0 1.50-2.10 1.05-1.15 con.i 6.5-8 Side dimorphism: Side dimorphism of the otoliths is not very strongly developed in Pleuronectes. Otoliths of the blind (left) side often show a peculiar deepening of the anterior portion of the ostium, a rather unique character in Pleuronectidae. Otoliths of the eyed (right) side may show a Schwarzhans: Pleuronectiformes 233 556a 556d 556c 556b 557d 557a 558 557b 557c 559b 559c 560b 560a 559a 560c Figs. 556-560: Parophrys vetulus GIRARD 1856 – 6 × less well developed separation of the colliculi and a slightly more convex inner face. In the case of Pleuronectes platessa I have studied the effects of side dimorphism in otoliths during ontogeny starting from early bottom living postlarval fishes of 30 to 60 mm length (se also chapters 6.2 and 6.3) (figs.). These otoliths, which are about 1.0 to 1.6 mm long, do not show the kind of side dimorphism described above from adults. Instead, there otoliths of the eyed (right) side exhibit a more pronounced postdorsal projection of the otolith rim than otoliths of the blind (left) side, a dimorphic character, which apparently gets lost later in ontogeny. Ontogeny and variability: The very small otoliths of postlarval stages (figs.) look like very generalized pleuronectid otoliths and certainly Piscium Catalogus, Part Otolithi piscium, Vol. 2 are not diagnostically mature. They are more compressed and roundish in outline and their rims less ornamented. The sulcus opening, however, is already reduced and the circumsulcal depression completely developed. It seems that diagnostic maturation of the otoliths is reached at about 4 mm of size. Discussion: The oval outline with the gently curving ventral rim and the peculiar deepening of the anterior portion of the ostium in otoliths of the blind (left) side characterizes otoliths of this genus. In a recent review of the Pleuronectidae SAKAMOTO (1984) has synonymized a number of genera with Pleuronectes. These are Isopsetta, Parophrys, Lepidopsetta, Limanda, Pseudopleuronectes and Liopsetta. Except for Isopsetta, which is quite 234 561b 561c 561a 562c 562b 562a 564 563 568c 569c 566 568a 567 568b 569a 565 569b Figs. 561-569: Pleuronectes platessa LINNAEAUS 1758 – figs. 561a, 562a, 563-567, 568c, 569c = 10 ×; figs. 561b,c, 562b,c = 6 ×; figs. 568a, b, 569a, b = 15 × Schwarzhans: Pleuronectiformes 235 distinct as far as otoliths are concerned, these genera are here placed in the Pleuronectes-Limanda Group and undoubtedly are closely interrelated with each other. Indeed, it seems that generic splitting may have been driven to far in this group, but with the present state of knowledge I do not feel in the position to comment on the basis of otoliths. Species and distribution: two species – P. platessa from the north-eastern Atlantic and P. pallasii from the northern, Arctic Pacific. Pleuronectes platessa LINNAEUS 1758 Figs. 561-569 syn. syn. syn. syn. Platessa vulgaris CLOQUET 1826 Pleuronectes borealis FABER 1828 Platessa lata CUVIER 1829 Pleuronectes baltica NILSSON 1855 Investigated otoliths: 12 otoliths (left and right) from the North Sea, ZMH Ot. 24.1.1995.6-17 (coll. Schwarzhans). Distribution: North-western Europe, from the White Sea to Spain, Iceland, and in the Adriatic; also as fossil from the Pleistocene of southern England. Platichthys GIRARD 1856 Type-species: Platichthys rugosus GIRARD 1856 (syn. P. stellatus) syn. Flesus MOREAU 1881 Diagnosis: Thin, rather elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with prominent postdorsal angle, slightly undulating, posterior tip blunt, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.55 to 1.85. Otolith size at least 6 mm. Otoliths below 3 mm not diagnostically mature. Ostium slightly wider than cauda and much longer. Index ol:cl 2.0 to 2.6. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi separated. Circumsulcal depression well developed, moderately wide, slightly deepened. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Inner face slightly convex and rather smooth; outer face flat and smooth. Rims sharp. Measurements: flesus stellatus l:h 1.55-1.70 1.65-1.85 h:t 3.2 3.2 ol:cl oh:ch con.i 2.00-2.50 1.35-1.55 5.5-8 2.50-2.60 1.5 about 5 Side dimorphism: Side dimorphism is moderately developed in this genus. The separation of the colliculi is less well developed in otoliths of the eyed (right) side, the inner face slightly more convex, the circumsulcal depression more shallow, and the postdorsal projection more pointed. Determination of side dimorphism in the otoliths of this genus is hampered by the common occurrence of reversed specimens. In particular in P. stellatus it has been noted that specimens from the North-West Pacific are almost always reversed, whereas in the North-East Pacific reversed and non-reversed specimens occur in about equal amounts. Reversal bears a strong impact in the otolith morphology, and this is being discussed in detail in chapter 6.4. Ontogeny and variability: Otoliths of a size down to about 3 mm do not differ greatly from larger ones and can be regarded as diagnostically mature. Variability is more considerable than in other genera of the Pleuronectidae and mainly concerns otolith and sulcus proportions. Again, the effects of reversal on otolith morphology are most notable. Discussion: Otoliths of the genus Platichthys are very similar to both the genera Kareius (placed in synonymy with Platichthys by NORMAN 1934) and Pleuronectes. NORMAN related this genus also to Liopsetta. Species and distribution: Two species – P. flesus from the North Atlantic and the Mediterranean and P. stellatus from the North Pacific. Platichthys flesus (LINNAEUS 1758) Figs. 570-572, 25 syn. syn. syn. syn. syn. Pleuronectes passer LINNAEUS 1758 Pleuronectes flesoides PONTOPPIDAN 1765 Pleuronectes roseus SHAW 1796 Scophthalmus diurus RAFINESQUE 1810 Pleuronectes luscus PALLAS 1814 236 syn. syn. syn. syn. syn. Platessa carnaria BROWN 1830 Platessa glabra RATHKE 1837 Pleuronectes passarinus NARDO 1847 Pleuronectes italicus GÜNTHER 1862 Pleuronectes bogdanovi SANDEBERG 1878 Investigated otoliths: 9 otoliths (4 left and 5 right, including 4 from reversed specimens, figs. 571572, 25), 8 from Plymouth, Great Britain, ZMH Ot. 24.1.1995.18-21 (leg. BMNH 1988.10.11.39-52) and BMNH 1988.10.11.39-52, and 1 from Portugal (fig. 570), ZMH Ot. 24.1.1995.22 (coll. Schwarzhans). Discussion: As a rule, otoliths of P. flesus are less elongate than those of P. stellatus. Distribution: Coasts of Europe, from the White Sea to the Mediterranean and the Black Sea; also as fossil from the Pleistocene of southern England. Platichthys stellatus (PALLAS 1787) Figs. 573-574, 24 syn. Platichthys rugosus GIRARD 1856 Investigated otoliths: 12 otoliths, 2 (left and right, non-reversed) from California, BMNH (Ayres coll.), 2 (left and right, non-reversed, figs. 573574, 24) from California, ZMH Ot. 24.1.1995.2324 (leg. BMNH 81.3.14.13), 4 (left and right, reversed, fig. 24) from California, ZMH Ot. 24.1.1995.25-26 (leg. BMNH, Ayres coll.) and BMNH, Ayres coll., 2 (left and right, reversed, fig. 24) from Kamchatka, ZMH Ot. 24.1.1995.2728 (leg. BMNH 91.12.21.40), and 2 (left and right, reversed, fig. 24) from the Rae’s collection, BMNH 53.9.19.1220. Discussion: Otoliths of “normal”, non-reversed specimens of P. stellatus differ from those of P. flesus in being somewhat more elongate. Distribution: North Pacific, Japan, Korea and southern California; fossil from the Pleistocene of California. Kareius JORDAN & SNYDER 1901 Type-species: Pleuronectes scutifer STEINDACHNER 1870 (syn. K. bicoloratus) Diagnosis: Thin, rather elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with postdorsal angle, posterior tip blunt, anterior tip somewhat projecting like a rostrum, rounded. All rims somewhat crenulated. Index l:h 1.5 to 1.75. Otolith size at least 5 mm. Ostium slightly wider than cauda and considerably longer. Index ol:cl 1.75 to 1.9. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus very slightly deepened. Colliculi separated. Circumsulcal depression well developed, moderately wide, slightly deepened. Inner face rather flat and smooth; outer face also flat and smooth. Rims sharp. Measurements: bicoloratus l:h h:t ol:cl oh:ch con.i 1.50-1.75 3.0-3.5 1.75-1.90 1.05-1.25 5.5-6.5 Side dimorphism: Weekly developed. The separation of the colliculi is less well developed in otoliths of the eyed (right) side. Also the postdorsal angle is more pointed and the ostium seemingly more narrow. Variability: The most variable character seems to be the index l:h of the otolith. Discussion: Kareius apparently is closely related to Platichthys (placed in synonymy by NORMAN, 1934). Main difference is the lesser index ol:cl and the fine marginal crenulation. Species and distribution: Kareius is a monospecific genus with K. bicoloratus known from the coasts of Japan, Korea and northern China. Kareius bicoloratus (BASILEWSKY 1855) Figs. 575-578 syn. Pleuronectes scutifer STEINDACHNER 1870 Investigated otoliths: 4 otoliths (left and right) from the Ise Bay, central Japan, coll. Ohe No. 751011-23 Schwarzhans: Pleuronectiformes 237 570a 570d 570c 570b 572a 571a 571c 572c 572b 571b 573b 573c 573a 574c 574a 574b Figs. 570-572: Platichthys flesus (LINNAEUS 1758) – 10 × Figs. 573-574: Platichthys stellatus (PALLAS 1787) – 10 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 238 Distribution: Japan, Korea and northern China. Pseudopleuronectes BLEEKER 1862 Type-species: Pleuronectes planus MITCHILL 1814 (syn. P. americanus) syn. Limandella (type-species: Pleuronectes yokohamae) Diagnosis: Thin, elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with postdorsal angle, usually irregularly undulating, predorsal angle sometimes developed, posterior tip blunt, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.65 to 1.8. Otolith size at least 6 mm. Otoliths below 3 mm probably not diagnostically mature. Ostium slightly wider than cauda and much longer. Index ol:cl 1.6 to 1.9. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi separated. Circumsulcal depression well developed, wide, slightly deepened. Inner face rather flat and smooth; outer face also flat and smooth. Rims sharp. Measurements: americanus yokohamae herzensteini l:h 1.70-1.80 1.65-1.80 1.80 h:t 3.0 3.0 3.0 ol:cl 1.60 1.70-1.90 1.70 oh:ch 1.2-1.3 1.0-1.2 1.3 con.i nm nm nm Side dimorphism: In the case of P. americanus the otolith from the eyed side seems to be slightly more elongate than the one from the blind side, but they are both rather small and probably not fully diagnostically mature. Discussion: Otoliths of the genus Pseudopleuronectes very closely resemble those of the genus Platichthys may be except for the somewhat less pronounced postdorsal angle. Nevertheless, based on otolith morphology they would probably not be regarded as representing separate genera. Species and distribution: Three species – P. americanus from the North-West Atlantic, P. yokohamae and P. herzensteini from the North-West Pacific. Pseudopleuronectes americanus (WALBAUM 1792) Figs. 579-580 syn. Pleuronectes planus MITCHILL 1814 syn. Platessa pusilla DE KAY 1842 syn. Pseudopleuronectes dignabilis KENDALL 1912 Investigated otoliths: 2 otoliths (left and right) from New Foundland, ZMH Ot. 28.1.1995.1-2 (leg. ZMH 20103). Discussion: The two investigated otoliths are relatively small (about 3 mm) and probably not fully diagnostically mature. They differ from those of the two other species of the genus in being more regularly rounded in outline. Distribution: Atlantic coast of North America from Labrador to Chesapeake Bay. Pseudopleuronectes yokohamae (GÜNTHER 1877) Figs. 581-582 syn. Limanda schrencki SCHMIDT 1904 Investigated otoliths: 2 otoliths (left side) from Hakata, Japan, ZMH Ot. 28.1.1995.3 (leg. BMNH 1923.2.26.630-32) and BMNH 1923.2.26.630-32. Discussion: Very similar to P. herzensteini but somewhat more elongated and with less pronounced predorsal angle. Distribution: Shores of Japan and Korea. Pseudopleuronectes herzensteini JORDAN & SNYDER 1901 Fig. 583 syn. Limanda angustirostris JORDAN & STARKS 1904 Investigated otoliths: 1 otolith (left side) from Japan, BMNH 1923.2.26.636-37 (identified as L. angustirostris) Discussion: Very similar to P. yokohamae (see respective entry). Distribution: Japan. Schwarzhans: Pleuronectiformes 239 575b 575c 575a 577 576a 576c 576b 578 579b 579a 579c 580 581a 581c 582 581b 583c 583b 583a Figs. 575-578: Kareius bicoloratus (BASILEWSKY 1855) – 10 × Figs. 579-580: Pseudopleuronectes americanus (WALBAUM 1792) – 10 × Figs. 581-582: Pseudopleuronectes yokohamae (GÜNTHER 1877) – 10 × Figs. 583: Pseudopleuronectes herzensteini JORDAN & SNYDER 1901 – 10 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 240 586 584a 584c 585 587 584b Figs. 584-587: Lepidopsetta bilineata (AYRES 1854) – 10 × Lepidopsetta GILL 1864 Type-species: Platichthys umbrosus GIRARD 1857 (syn. L. bilineata) (sensu NORMAN, 1934). In accordance with NORMAN they seem to be closest related to Limanda or Pseudopleuronectes. Diagnosis: Thin, moderately elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with pre- and postdorsal angles, smooth, posterior tip rounded, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.45 to 1.55. Otolith size at least 5 mm. Otoliths below 3 mm not diagnostically mature. Ostium slightly wider than cauda and much longer. Index ol:cl 1.9 to 2.0. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi separated. Circumsulcal depression well developed, wide, slightly deepened. Inner face rather flat and smooth; outer face also flat and smooth. Rims sharp. Species and distribution: Two species – L. bilineata and L. mochigarei from the northern Pacific. Lepidopsetta bilineata (AYRES 1854) Figs. 584-587 syn. Platichthys umbrosus GIRARD 1857 syn. Pleuronectes perarcuatus COPE 1873 Investigated otoliths: 4 otoliths (left and right) from California, ZMH Ot. 28.1.1995.4-7 (leg. Fitch). Distribution: Pacific coast of North America from the Bering Sea to California and in the Okhotsk Sea. Measurement: bilineata l:h 1.45-1.55 h:t 3.5 ol:cl oh:ch con.i 1.90-2.00 1.05-1.1 about 5 Side dimorphism: Very feeble. Otoliths of the eyed side show a somewhat narrower sulcus and less well separated colliculi. Ontogeny: Smaller specimens below 3 mm length already show rather generalized pleuronectid-type otoliths and are not diagnostically mature. Discussion: Otoliths of the genus Lepidopsetta are not very characteristic amongst Pleuronectinae Inopsetta JORDAN 1887 Type-species: Parophrys ishyrus JORDAN & GILBERT 1881 Diagnosis: Moderately thin and elongate otoliths; ventral rim shallow, gently curving, deepest at about the middle, dorsal rim with prominent postdorsal and less pronounced predorsal angle, somewhat undulating, posterior tip blunt, undulating, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.60 to 1.65. Otolith size at least 5 mm. Schwarzhans: Pleuronectiformes 241 589 588a 588c 588b Figs. 588-589: Inopsetta ishyra (JORDAN & GILBERT 1881) – 10 × Ostium about as wide as cauda, but much longer. Index ol:cl 2.0 to 2.2. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Cauda slightly deepened. Colliculi separated. Circumsulcal depression well developed, wide, slightly deepened. Inner face slightly convex and rather smooth; outer face flat and slightly ornamented. Rims sharp. Measurement: ishyra l:h 1.60-1.65 h:t 3.0 ol:cl 2.00-2.20 oh:ch 1.0 con.i 5 Side dimorphism: Very feeble. The separation of the colliculi in otoliths of the eyed side is not well developed. Discussion: Otoliths of the genus Inopsetta closely resemble those of Lepidopsetta, except for being more elongated. Other related genera apparently are Platichthys and Pseudopleuronectes. NORMAN (1934) assumed that Inopsetta ishyra may prove to be a hybrid between Lepidopsetta bilineata and Platichthys stellatus. Species and distribution: Inopsetta ishyra is a monospecific genus with I. ishyra restricted to the Puget Sound, Pacific coast of North America. Inopsetta ishyra (JORDAN & GILBERT 1881) Figs. 588-589 Investigated otoliths: 2 otoliths (left and right) from the Puget Sound, ZMH Ot. 28.1.1995.8-9 (leg. ZMH 20022). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Puget Sound, Pacific coast of North America. 7.7.5 Isopsetta Group Genera: Two monospecific genera from the Pacific coasts of North America – Psettichthys and Isopsetta. Definition and relationship: In this small and specialized group I have placed two genera which are characterized by the following otolith pattern. The otoliths are compressed, moderately thickset, with prominent pre- and postdorsal angles and a reduced ostial opening. The sulcus is shallow and very characteristic due to the elevated rims of the colliculi, which are clearly separated. In general appearance, these otoliths could even be mistaken for some kind of Soleidae. Side dimorphism is faintly developed in the genera of this group. NORMAN (1934) placed these two genera at quite different systematic positions within the Pleuronectinae and apparently felt that they were not particularly related to each other. Psettichthys he related to Hippoglossoides and other large and symmetrically mouthed genera, whereas Isopsetta was placed in the group of genera with small mouths and asymmetrical jaws and dentition (here mainly placed in the Pleuronectes-Limanda Group). It can therefore not be excluded that the observed similarities of the otolith morphology represent an analogous development only. 242 590a 591 590c 590b Figs. 590-591: Psettichthys melanostictus GIRARD 1854 – 10 × Psettichthys GIRARD 1854 Type-species: Psettichthys melanostictus GIRARD 1854 Diagnosis: Moderately thin, rather compressed, otoliths with almost rectangular outline; ventral rim very shallow, gently curving, deepest at about the middle, dorsal rim with prominent pre- and postdorsal angles, posterior tip blunt, anterior tip somewhat projecting like a rostrum, short and rounded. All rims slightly undulating. Index l:h 1.4 to 1.5. Otolith size at least 5 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 2.00. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus shallow. Colliculi separated, their rims somewhat elevated, the central portion somewhat deepened. Circumsulcal depression well developed, not very wide, slightly deepened. Inner face rather flat and smooth; outer face also flat and slightly ornamented. Rims sharp. Measurement: melanostictus l:h 1.40-1.50 h:t 3.0 ol:cl 2.00 oh:ch 1.2-1.3 con.i nm Side dimorphism: No data. Discussion: According to otolith morphology close to Isopsetta, but with somewhat less compressed otoliths. NORMAN’s supposed relation to Hippoglossoides is not confirmed by otoliths. Species and distribution: Psettichthys is a monospecific genus with P. melanostictus restricted to the Pacific coast of North America. Psettichthys melanostictus GIRARD 1854 Figs. 590-591 Investigated otoliths: 2 otoliths (left side) from off Oregon, USA, ZMH Ot. 28.1.1995.10 (leg. BMNH 95.12.31.51-52) and BMNH 95.12.31.51-52. Distribution: Pacific coast of North America, from Sitka (Alaska) to Monterey (California). Isopsetta JORDAN & GILBERT 1882 Type-species: Lepidopsetta isolepis LOCKINGTON 1880 Diagnosis: Moderately thickset, compressed, roundish otoliths; ventral rim gently curving, deepest at about the middle, dorsal rim with prominent pre- and postdorsal angles, posterior tip blunt, anterior tip slightly projecting, short and rounded. Rims smooth to slightly undulating. Index l:h 1.1. Otolith size at least 5 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 1.9 to 2.2. Ostial opening reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus shallow. Colliculi separated, their rims somewhat elevated, the central portion somewhat deepened. Circumsulcal depression well developed, not very wide, slightly deepened. Inner face slightly convex and smooth; outer face flat and rather smooth. Rims not very sharp. Measurement: isolepis l:h 1.10 h:t 3.0 ol:cl 1.90-2.20 oh:ch 1.05 con.i about 4 Schwarzhans: Pleuronectiformes 243 592c 592a 593 592b Figs. 592-593: Isopsetta isolepis (LOCKINGTON 1881) – 10 × Side dimorphism: Very feeble. Otoliths of the eyed side show a slightly less well developed separation of the colliculi and are also more rounded in outline. Discussion: Otoliths of the genus Isopsetta could almost be mistaken for some kind of Soleidae due to their compressed appearance and the general habitus of the sulcus. Amongst Pleuronectidae Psettichthys comes closest, but its otoliths are less compressed. Species and distribution: Isopsetta is a monospecific genus with I. isolepis from the Pacific coast of North America. Isopsetta isolepis (LOCKINGTON 1881) Figs. 592-593 Investigated otoliths: 2 otoliths (left and right) from California, ZMH Ot. 28.1.1995.11-12 (leg. Fitch). Distribution: Pacific coast of North America, from Puget Sound to southern California; fossil from the Pleistocene of California. 7.7.6 Verasper Group Genera: Two genera from the North-West Pacific – Verasper and Clidoderma. Definition and relationship: Otoliths of the fishes of the Verasper Group are readily recognized by their long and wide sulcus which reaches relatively close to the posterior rim of the otolith Piscium Catalogus, Part Otolithi piscium, Vol. 2 and anteriorly shows almost no reduction of the ostial opening. Also the cauda is comparatively long as compared to the pleuronectid groups described before. All these characters are distinctly plesiomorphic for pleuronectidae and the character status thus is only comparable to that found in the Hippoglossus Group (see respective entry). Presumably the Verasper Group represents a very early split-off from the main pleuronectid stem and in turn possibly gave rise to the MicrostomusPleuronichthys and may be even the Samaris Groups. In both these groups the sulcus clearly opens anteriorly, often with a distinct excisura and is considerably deepened. NORMAN (1934) also did not feel too certain about the outside relationship of these two closely related genera. To Clidoderma he noted that ‘this aberrant genus in some respects forms a connecting link between the large and symmetricalmouthed genera and those in which the jaws and dentition are markedly asymmetrical’. As this concept of subdividing the Pleuronectinae may now need to be abandoned (see general entries to Pleuronectidae and group definitions) the genera of the Verasper Group probably occupy a more “primitive” position within the Pleuronectidae, closer to the basal branching in this family. Verasper JORDAN & EVERMANN 1898 Type-species: Verasper moseri JORDAN & EVERMANN 1898 Diagnosis: Moderately thin, not very elongate otoliths; ventral rim very shallow, smooth, gently curving, deepest at about the middle, dorsal rim with strong postdorsal and less well developed predorsal angles, rather smooth, posterior 244 595 594a 594c 594b 596a 596b 596c Figs. 594-596: Verasper variegatus (TEMMINCK & SCHLEGEL 1846) – 10 × tip blunt, with small notch at about the level of the cauda, ventrally projecting strongest, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.45 to 1.55. Otolith size at least 6 mm. Ostium slightly wider than cauda and not much longer at all. Index ol:cl 1.1 to 1.4. Ostium nearly opening anteriorly, only very slightly reduced. Cauda tapering, terminating not far from the posterior tip of the otolith. Sulcus somewhat deepened. Colliculi poorly separated. Circumsulcal depression well developed, moderately wide, slightly deepened. Inner face rather flat and relatively smooth; outer face slightly convex and smooth. Rims sharp. Discussion: Otoliths of the genus Verasper very closely resemble those of the related genus Clidoderma, which is in full agreement with NORMAN’s relating of the two genera. Otoliths of Clidoderma are somewhat more elongate and show a less deepened sulcus. Measurements: Investigated otoliths: 4 otoliths, 3 (2 left and 1 right) from Tsingtao, China, IRSNB (coll. Nolf) and 1 (left side) from the Inland Sea of Japan, BMNH 1905.6.6.230-1. variegatus l:h 1.45-1.55 h:t 3.0 ol:cl 1.10-1.40 oh:ch 1.2-1.4 con.o about 3 Side dimorphism: Otoliths of the eyed side are more roundish in outline, particularly in respect to the rostrum and the predorsal angle. At the posterior tip of the otolith the postdorsal angle is projecting further than the posterior-ventral portion. The sulcus and in particular the ostium is somewhat narrower. Species and distribution: Two species – V. moseri and V. variegatus from Japan, the Kuril Islands and China. Verasper variegatus (TEMMINCK & SCHLEGEL 1846) Figs. 594-596 Distribution: Seas of southern Japan and northern China. Schwarzhans: Pleuronectiformes 245 Clidoderma BLEEKER 1862 Type-species: Platessa asperrima TEMMINCK & SCHLEGEL 1846 Diagnosis: Moderately thin and moderately elongate otoliths; ventral rim very shallow, smooth, gently curving, deepest at about the middle, dorsal rim with moderate pre- and postdorsal angles, rather smooth, posterior tip blunt, with small concavity at about the level of the cauda, ventrally projecting strongest, anterior tip somewhat projecting like a rostrum, rounded. Index l:h 1.6. Otolith size at least 5 mm. Ostium slightly wider than cauda and not much longer at all. Index ol:cl 1.4. Ostium nearly opening anteriorly, only very slightly reduced. Cauda rounded, terminating not far from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi poorly separated. Circumsulcal depression well developed, not wide, slightly deepened. Inner face flat and relatively smooth; outer face slightly convex and smooth. Rims sharp. Measurements: asperrimum l:h 1.60 h:t 3.2 ol:cl 1.40 oh:ch 1.05 con.o about 3.5 Side dimorphism: No data. Discussion: Very close to Verasper (see respective entry). Species and distribution: Clidoderma is a monospecific genus with C. asperrimum from Japan. Clidoderma asperrimum (TEMMINCK & SCHLEGEL 1846) Fig. 597 Investigated otoliths: 1 otolith (left side) from the Mutsu province, Japan, BMNH 1923.9.28.13. Distribution: Coasts of Japan, chiefly northward; fossil from the Upper Pliocene of Japan. 7.7.7 Microstomus-Pleuronichthys Group Genera: Four genera from the northern Atlantic and the northern Pacific – Microstomus, Embassichthys, Pleuronichthys and Hypsopsetta. Piscium Catalogus, Part Otolithi piscium, Vol. 2 a c b Fig. 597: Clidoderma asperrima (TEMMINCK & SCHLEGEL 1846) – 10 × Definition and relationship: In this group I have combined a number of genera with otoliths which besides the Samaris Group stick out immediately from the other Pleuronectidae. Its otoliths are relatively small and readily recognized by the long and deep sulcus which either reaches very close to the anterior rim of the otoliths or even opens to it (but different from the Samaris Group without a clear excisura). Ostium and cauda are of about equal length, although the ostium is usually slightly longer and wider. Margins and separation of the colliculi are very feeble. In many aspects these otoliths resemble more certain Bothidae (like in the Bothus Group) than Pleuronectidae. However, in this case it may not represent a plesiomorphic character but a secondary development. I assume that this kind of otolith morphology has developed from a character status as found in the Verasper Group, from near which it may have originated as a specialized lineage. Again it documents, that NORMAN’s pleuronectin grouping of genera with a small and asymmetrical mouth is not natural (see also general chapter to Pleuronectidae). The four genera placed in this group could also be seen as two sub-groups of two closely related genera each. One of these subgroups combines Pleuronichthys and Hypsopsetta, which NORMAN (1934) also placed close to Verasper and Clidoderma (see entry to Verasper Group). The other two genera – Microstomus and Embassichthys – he related to Pseudopleuronectes and related genera, placed here in the Pleuronectes-Limanda Group. This supposed relationship clearly is not supported by otolith morphology. However, the degree 246 of interrelationship of these two subgroups as based on otoliths still remains somewhat questionable (hence the double name MicrostomusPleuronichthys Group). Discussion: Otoliths of the genus Microstomus in many aspects resemble those of the genera Pleuronichthys and Hypsopsetta, but are more compressed and easily characterized by the anteriorly narrowing outline. Microstomus GOTTSCHE 1835 Type-species: Microstomus latidens GOTTSCHE 1835 (syn. M. kitt) Species and distribution: Four species – M. kitt from the North-East Atlantic and M. achne, M. shuntovi and M. pacificus from the northern Pacific (the latter also as fossil from the Pleistocene of California). syn. Cynicoglossus BONAPARTE 1837 [1846] (type-species: Pleuronectes microcephalus) syn. Brachyprosopon BLEEKER 1862 (type-species: Pleuronectes microcephalus) syn. Veraequa JORDAN & STARKS 1904 (typespecies: V. achne) Diagnosis: Small, compact, moderately thickset, ovale otoliths; ventral rim very shallow, gently curving, deepest at about the middle, dorsal rim gently curving as well, posterior tip blunt or rounded, anterior tip somewhat narrowing, with very faint indication of a rostrum. All rims smooth. Index l:h 1.40 to 1.45. Otolith size probably not exceeding 4 mm. Ostium about as wide as cauda and not much longer at all. Index ol:cl 1.2 to 1.4. Ostium opening anteriorly or reaching very close to the anterior rim of the otolith. Cauda terminating not far from the posterior tip of the otolith. Sulcus considerably deepened. Colliculi poorly defined and separated. Circumsulcal depression faint, narrow. Inner face rather flat and not smooth; outer face slightly convex and smooth. Rims sharp. Measurements: kitt l:h h:t ol:cl oh:ch con.i 1.40-1.45 3.0-3.5 1.20-1.40 1.0-1.15 about 8 Side dimorphism: Side dimorphism is feeble in this genus and masked by the high degree of variability. In otoliths of the eyed side the colliculi are less separated. Variability: The variability in this genus apparently is very high (refer also to figures by CHAINE, 1936) and concerns mainly the outline of the otoliths. Although I have investigated only otoliths of one recent species (M. kitt) it seems that the species will not be easily distinguished by means of otoliths judging from the low level of diagnostic features and the high level of variability. Microstomus kitt (WALBAUM 1792) Figs. 598-601 syn. syn. syn. syn. syn. syn. syn. Pleuronectes microcephalus DONOVAN 1803 Pleuronectes laevis SHAW 1803 Pleuronectes quenselii HOLLBERG 1821 Pleuronectes quadridens FABRICIUS 1828 Pleuronectes microstomus FABER 1828 Platessa pola CUVIER 1829 Microstomus groenlandicus REINHARDT 1839 syn. Pleuronectes gilli STEINDACHNER 1868 Investigated otoliths: 5 otoliths (2 left and 3 right) from the North Sea, ZMH Ot. 29.1.1995.1-5 (coll. Schwarzhans). Distribution: Coasts of north-western Europe, from the White Sea to the Bay of Biscay and to Iceland. Embassichthys JORDAN & EVERMANN 1896 Type-species: Cynicoglossus bathybius GILBERT 1891 Remarks: Embassichthys is a monospecific genus with E. bathybius known from the deeper waters off the Pacific coast of North America and Japan. Otoliths have not been available for investigation. According to NORMAN (1934) Embassichthys is closely related to Microstomus. Pleuronichthys GIRARD 1856 Type-species: Pleuronichthys coenosus GIRARD 1856 syn. Heteroprosopon BLEEKER 1862 (type-species: Platessa cornuta) Schwarzhans: Pleuronectiformes 247 599 598 600a 600c 600b 601 Figs. 598-601: Microstomus kitt (WALBAUM 1792) – 10 × Diagnosis: Moderately thin, elongate otoliths; ventral and dorsal rim very shallow, gently curving, deepest at about their respective middle, dorsal rim with feeble postdorsal and broad predorsal angle, posterior tip blunt, usually ventrally projecting, anterior tip somewhat projecting like a rostrum, rounded or somewhat pointed. Rims usually smooth. Index l:h 1.7 to 1.95. Otolith size not exceeding 6 mm. Otoliths smaller than 3.5 to 4 mm probably not fully diagnostically mature. Ostium slightly wider than cauda and not much longer. Index ol:cl variable, 1.2 to 2.0. Ostium nearly opening anteriorly, only very slightly reduced. Cauda terminating not very far from the posterior tip of the otolith. Sulcus markedly deepened. Colliculi poorly defined and separated. Circumsulcal depression well developed, narrow, slightly deepened. Inner face rather flat, not smooth; outer face slightly convex or flat and smooth. Rims moderately sharp to sharp. Variability of the otoliths of Pleuronichthys is considerable and affects outline as well as proportions of sulcus and otolith. In fact, differentiation of the various species by means of otoliths alone may not always be possible due to overlap in characteristics caused by this high degree of intraspecific variations. Discussion: Pleuronichthys apparently is closely related to Hypsopsetta. Micromesistius is also similar but its otoliths are more compressed. All three genera share the long and deep sulcus, opening (or nearly opening) to the anterior rim. Species and distribution: Seven species – P. cornutus from the North-West Pacific (also as fossil from the Pliocene of Japan) and P. coenosus, P. decurrens, P. nephelus, P. ocellatus, P. ritteri and P. verticalis from the Pacific coast of North America. Pleuronichthys coenosus GIRARD 1856 Figs. 602-605 Measurements: coenosus decurrens verticalis ritteri l:h h:t 1.75-1.95 2.5-3.3 1.75-1.80 3.2 1.70-1.95 3.0 1.80-1.90 2.4-3.2 ol:cl 1.5-2.0 1.7-2.0 1.5-2.0 1.5-1.7 oh:ch 1.0-1.1 1.0-1.1 1.0-1.1 1.3-1.5 con.i 5-6 about 8 about 6 7-8 Side dimorphism: Side dimorphism in the otoliths of this genus is very inconspicuous or else masked by the high degree of variability. In some species otoliths of the eyed side show a less pronounced posterior-ventral projection. Ontogeny and variability: Otoliths smaller than 3.5 to 4 mm are usually thinner than the larger ones and less ornamented. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 4 otoliths (left and right) from California, ZMH Ot. 29.1.1995.6-9 (leg. Fitch). Discussion: P. coenosus is hardly distinguishable from P. decurrens and P. verticalis. Its otoliths are usually somewhat more elongate than those of P. decurrens and, at least in large specimens, more thickset than those of P. verticalis. Distribution: Coast of California. 248 603 602c 602a 602b 604a 604b 605 607 606c 606a 606b 608 609 Figs. 602-605: Pleuronichthys coenosus GIRARD 1856 – 10 × Figs. 606-609: Pleuronichthys decurrens JORDAN & GILBERT 1881 – 10 × Pleuronichthys decurrens JORDAN & GILBERT 1881 Figs. 606-609 syn. Pleuronichthys quadrituberculatus JORDAN & GILBERT 1881 Discussion: Very similar to P. coenosus and P. verticalis but usually somewhat more compressed and with a less pronounced postdorsal projection. Rostrum very short. Distribution: Pacific coast of North America, from Alaska to California. Investigated otoliths: 4 otoliths (left and right) from California, ZMH Ot. 29.1.1995.10-13 (leg. Fitch). Schwarzhans: Pleuronectiformes 249 611 610a 610c 610b 616 612 614 613 615 617 Figs. 610-617: Pleuronichthys verticalis JORDAN & GILBERT 1881 – 10 × Pleuronichthys verticalis JORDAN & GILBERT 1881 Figs. 610-617 Investigated otoliths: 8 otoliths (left and right) from California, ZMH Ot. 29.1.1995.14-21 (leg. Fitch). Discussion: Otoliths of P. ritteri may be recognized by their widened ostium (see index oh:ch) distinguishing it from the other three species investigated. Distribution: California, also fossil from the Pleistocene. Discussion: Very similar to P. coenosus but usually with a more pronounced postdorsal projection and also somewhat thinner. Hypsopsetta GILL 1863 Type-species: Pleuronichthys guttulatus GIRARD 1857 Distribution: California and Gulf of California. Diagnosis: Rather thickset, Moderately elongate otoliths; ventral rim gently curving, deepest slightly anterior of the middle, dorsal rim with pronounced postdorsal and less pronounced predorsal angle, otherwise straight, posterior tip blunt, nearly vertically cut, anterior tip somewhat projecting like a rostrum, broadly rounded. Rims smooth or irregularly undulating. Index l:h 1.5 to 1.75. Otolith size not exceeding 5 to 6 mm. Ostium markedly wider than cauda and longer. Index ol:cl 1.6 to 2.0. Ostium nearly opening Pleuronichthys ritteri STARKS & MORRIS 1907 Figs. 618-621 Investigated otoliths: 4 otoliths (left and right) from California, ZMH Ot. 29.1.1995.22-25 (leg. Fitch). Piscium Catalogus, Part Otolithi piscium, Vol. 2 250 619 618a 618c 618b 621 620b 620a Figs. 618-621: Pleuronichthys ritteri STARKS & MORRIS 1907 – 10 × anteriorly, only very slightly reduced. Cauda terminating not very far from the posterior tip of the otolith. Sulcus markedly deepened. Colliculi poorly defined and separated. Circumsulcal depression well developed, narrow, slightly deepened. Inner face rather flat, not smooth; outer face flat and rather smooth. Rims not very sharp. guttulatus (left) guttulatus (right) syn. Parophrys ayresii GÜNTHER 1862 Investigated otoliths: 4 otoliths (left and right) from California, ZMH Ot. 29.1.1995.26-29 (leg. Fitch). Distribution: California. Measurements: l:h 1.70-1.75 1.50-1.55 Hypsopsetta guttulata (GIRARD 1857) Figs. 622-625 h:t 2.6 2.6 ol:cl 1.60-1.75 1.85-2.00 oh:ch 1.2-1.4 1.3 con.i 3.5 3.5 Side dimorphism: Quite markedly. Otoliths of the eyed side are more compressed due to a more deeply curving ventral rim. Also the postdorsal angle is somewhat projecting and the index ol:cl is somewhat higher. Discussion: Otoliths of the genus Hypsopsetta are very similar to those of Pleuronichthys but somewhat more compressed and with a different development of the posterior rim. Species and distribution: Two species from the Pacific coast of North America – H. guttulata and H. macrocephala. Rhombosoleinae 7.7.8 Pelotretis Group Genera: A single monospecific genus – Pelotretis – endemic to New Zealand. Definition and relationship: The elongate and thin otoliths of the genus Pelotretis could go as a Bothidae as well as a Pleuronectidae. The long and distinctly inframedian rostrum, the only very slightly reduced ostial opening and the long sulcus reaching relatively close to the posterior tip of the otolith all resemble otoliths of certain bothid genera (Paralichthys Group) and even Lepidorhombus of the Scophthalmidae. The genus Pelotretis is one of those enigmatic right eyed flatfishes of the southern Australian and New Zealandian region that NORMAN (1934) had combined in the subfamily Rhombosoleinae. The Rhombosoleinae are here regarded Schwarzhans: Pleuronectiformes 251 623a 622a 622c 623b 622b 625 624 Figs. 622-625: Hypsopsetta guttulata (GIRARD 1857) – 10 × as a polyphyletic group and its members have been re-arranged in groups partly outside the Pleuronectidae (see chapter 5.3.2. and introduction to Pleuronectidae). Pelotretis tentatively is left with the Pleuronectidae, but its relationship remains unclear as from otolith morphology. However, it may possibly be related to the genus Rhombosolea (Rhombosolea Group), and together with it is tentatively left in the much reduced subfamily Rhombosoleinae. Pelotretis WAITE 1911 Type-species: Pelotretis flavilatus WAITE 1911 Diagnosis: Thin, elongate otoliths; ventral rim very shallow, dorsal likewise shallow, shorter, without prominent angles, posterior tip irregularly rounded or inframedianly pointed, anteriorly a long and inframedian, thereby massive and often pointed rostrum. Index l:h 1.7 to 1.85. Otolith size up to about 6 mm. Ostium slightly wider than cauda and much longer. Index ol:cl 2.0 to 2.6. Ostium anteriorly open, just very slightly reduced. Cauda short, terminating not far from the posterior tip of the otolith. Sulcus rather shallow. Colliculi separated. Circumsulcal depression well developed, moderately wide, slightly deepened. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Inner face rather flat and smooth; outer face also flat and smooth. Rims sharp. Measurements: flavilatus l:h h:t ol:cl 1.70-1.85 3.2-3.8 2.00-2.60 oh:ch 1.1-1.2 con.i about 8 Side dimorphism: Affecting many characters, but in total rather moderate. Otoliths of the eyed side show less well separated colliculi, a more rounded posterior-dorsal portion of the rim and sometimes a faint excisura. Also the circumsulcal depression is better developed around the posterior tip of the cauda and often ornamented with delicate radial furrows. Finally, the inner face of right (eyed) side otoliths is just slightly more convex. Variability: Moderate, restricted to few details of the outline and the sulcus proportions. Discussion: See entry to group. Species and distribution: Pelotretis is a monospecific genus with P. flavilatus endemic to New Zealand. 252 Pelotretis flavilatus WAITE 1911 Figs. 626-630 Investigated otoliths: 6 otoliths, 4 (left and right, figs.) from New Zealand, AIM 2759 (coll. Grenfell), 2 (left and right) from off Wellington, New Zealand, BMNH 1935.3.14.216. Distribution: Shores of New Zealand and Chatham Islands. Remarks: A potential fossil representative of Pelotretis is figured for further comparison (fig. 631; Pelotretis sp. from the Lower Pliocene, Wanganuian, of Martinborough, New Zealand, coll. Pfeil, BSP). This otolith probably represents a subadult with a not fully mature morphology. 7.7.9 Rhombosolea Group Genera: A single genus – Rhombosolea – from the coasts of southern Australia and New Zealand. Definition and relationship: Otoliths of Rhombosolea again are rather typical pleuronectids, not much unlike those found in the PleuronectesLimanda Group. Characteristic is the not much reduced ostial opening and the ventral and dorsal portions of the inner face, which are strongly bent outward. Rhombosolea is the one genus of NORMAN’s Rhombosoleinae which remains at its position relative to the Pleuronectidae (see also chapter 5.2.3 and introduction to Pleuronectidae). Of the other “former” Rhombosoleinae only the genus Pelotretis (Pelotretis Group) may possibly be related and is kept in that subfamily. Rhombosolea GÜNTHER 1862 Type-species: Rhombosolea monopus GÜNTHER 1862 (syn. R. plebeia) syn. Bowenia HAAST 1873 (type-species: B. novaezeelandiae, syn. R. plebeia) syn. Apsetta KYLE 1900 (type-species: A. thompsoni, syn. R. plebeia) syn. Adamasoma WHITLEY & PHILLIPS 1939 (type-species: Rhombosolea retiaria) Diagnosis: Rather thin, moderately elongate otoliths; ventral and dorsal rims gently and regular- ly curving, but often intensely ornamented, sometimes with tendency to fenestrate development, posterior tip usually rounded, anterior tip blunt or with somewhat projecting rostrum. Index l:h 1.35 to 1.60. Otolith size up to 8 mm. Otoliths below 4 to 4.5 mm representing a quite distinct ontogenetic stage (see below). Ostium slightly wider than cauda and longer. Index ol:cl 1.45 to 2.25. Ostial opening only slightly reduced. Cauda moderately short, terminating not very far from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi not very well separated. Circumsulcal depression well developed, wide, moderately deepened. Inner face almost flat in the horizontal direction, but rather strongly convex in the vertical direction due to the marginal portions of the ventral and sometimes also dorsal field being bend outward; outer face concave, rarely flat, usually intensely ornamented. Rims sharp. Measurements: l:h plebeia (adult) 1.45-1.50 plebeia (juv., left) 1.35 plebeia (juv., right) 1.40 leporina (ad.,left) 1.45-1.55 leporina (ad., right) 1.65 tapirina (ad., left) 1.45-1.50 tapirina (ad., right) 1.60-1.65 tapirina (juv., left) 1.45 tapirina (juv., right) 1.40 retiaria 1.50 h:t ol:cl oh:ch con.i 3.0 1.60-1.70 1.2-1.3 about 6 4.0 1.90 1.25 nm 4.0 1.70 1.05 nm 3.5 1.8-1.9 1.2-1.3 about 5 4.0 1.60 1.5 about 6 4.0 2.20-2.25 1.4-1.5 about 5 4.0 1.60 1.2-1.3 about 5 3.0 (3.3) 1.1 about 7 3.0 1.60 1.3 about 10 3.5 1.80 1.15 about 4 Side dimorphism: Rhombosolea no doubt is one of the genera with more remarkable side dimorphism in otoliths. Furthermore, side dimorphism in Rhombosolea is special in two aspects – first, unlike in most flatfishes it is the otolith of the blind side which departs from the “normal” morphology in most aspects, and secondly side dimorphism of subadults is distinctively different from that of adults (see also chapters 6.3 and 6.5; figs. 632-635, 638-643). This has best been studied with otoliths of the species R. tapirina. In adults otoliths of the blind (left) side (larger than 4 to 4.5 mm) are more compressed, show a tendency to develop a thin, deep excisura, show less well separated colliculi, a higher index ol:cl, and sometimes a lesser index oh:ch. In smaller otoliths (less than 4 to 4.5 mm) those of the blind (left) side may show a rostrum and a clear ostial opening, which those of the right side may not show. The index ol:cl is higher and the index oh:ch lesser in otoliths of the blind side. Schwarzhans: Pleuronectiformes 253 627a 626a 626b 627b 628 629 631a 630 631b Figs. 626-630: Pelotretis flavilatus WAITE 1911 – 10 × Fig. 631: Pelotretis sp. – 10 × Otoliths of the eyed side show a more flat inner face. Ontogeny and variability: Apart from the change in quality of the side dimorphism there are some other prominent ontogenetic changes in otolith morphology as well. Smaller otoliths (less than 4 to 4.5 mm) have less ornamented margins, sometimes a well developed postdorsal angle and the inner face is much less convex in the vertical direction (i.e. the dorsal and ventral fields are not as yet bend outward). Also, these otoliths often show a clear rostrum (at least those of the left, blind side), which is unknown from adults (except for the species R. retiaria). (See also chapter 6.3) Piscium Catalogus, Part Otolithi piscium, Vol. 2 In the light of all these morphological changes it comes as a relief that at least the variability is not extraordinary. Variations are mainly restricted to the irregularly ornamented outline of the otoliths. Discussion: See entry to group. Species and distribution: Four species from the temperate seas of Australia and New Zealand – R. plebeia, R. leporina, R. tapirina and R. retiaria. 254 Rhombosolea plebeia (RICHARDSON 1843) Figs. 632-635 syn. Rhombosolea monopus GÜNTHER 1862 syn. Bowenia novaezeelandiae HAAST 1873 syn. Apsetta thompsoni KYLE 1900 Investigated otoliths: 4 otoliths from New Zealand, 1 (adult right, fig. 632) ZMH Ot. 31.1.1995.1 (leg. ZMH 20106), 1 (adult right, fig. 633) AUG-V 289 (coll. Grenfell), 2 (subadult left and right, figs. 634-635) AIM 2761 (coll. Grenfell). Discussion: Otoliths of the three species R. plebeia, R. leporina and R. tapirina are all very similar to each other. May be those of R. plebeia are the most compressed of these. Distribution: New Zealand and Auckland Islands, records from Australia doubtful as to NORMAN (1934). versed left and right, figs. 26) from Dunedin, New Zealand, BMNH 76.3.25.1. Discussion: Very similar to R. leporina (see respective entry). Otoliths of this species have been used to analyze side dimorphism occurring in this genus as well as ontogenetic changes and the combined effects of the two (see entry to genus). Finally, a representative of this species was selected to analyze effects of reversal on otolith morphology. The otoliths of the reversed specimen were found to be completely out of bounds, showing very little resemblance to otoliths of “normal” non-reversed specimens (see chapter 6.4 for detailed discussion). Distribution: Southern temperate Australia, New Zealand, Auckland and Campbell Islands. Rhombosolea retiaria HUTTON 1873 Fig. 644 Rhombosolea leporina GÜNTHER 1862 Figs. 636-637 Investigated otoliths: 1 otolith (left) from New Zealand, BMNH 1935.3.14.227. syn. Rhombosolea millari WAITE 1911 Investigated otoliths: 3 otoliths from New Zealand, 2 (left) AUG-V 289 (coll. Grenfell), 1 (right) BMNH 73.12.13.71-3. Discussion: Very similar to R. tapirina. If there is any discernable difference between the otoliths of the two species it is that those of R. leporina show a more regular outline with a much smoother dorsal rim. In left hand otoliths the ostium is rather narrow as compared to R. tapirina. Discussion: Easily recognized by its smooth and gently curving dorsal rim and the rather massive and long rostrum. This the only species of Rhombosolea in which otoliths from adults show a distinct rostrum. Distribution: New Zealand, entering fresh water. Samarinae 7.7.10 Samaris Group Distribution: Australia and New Zealand. syn. Rhombosolea flesoides GÜNTHER 1863 syn. Pleuronectes victoriae CASTELNAU 1872 Genera: This group combines three genera of NORMAN’s Samarinae – Samaris, Samariscus and Plagiopsetta – plus a fourth genus from his Rhombosoleinae – Azygopus. Geographical distribution is chiefly the tropical and subtropical Indo-Pacific, with the exception of Azygopus which is restricted to temperate Australia and New Zealand. Investigated otoliths: 8 otoliths, 4 (adult left and right, figs. 638-641) from New Zealand, AIM 2762 (coll. Grenfell), 2 (subadult left and right, figs. 642-643) from Port Philipp, Australia, ZMH Ot. 31.1.1995.2-3 (leg. ZMH 20107), and 2 (adult re- Definition and relationship: The fishes of the genera placed in the Samaris Group show a number of unique specializations (except for Azygopus, which is placed here mainly because of similarity in otolith morphology). According to Rhombosolea tapirina GÜNTHER 1862 Figs. 638-643, 21, 26 Schwarzhans: Pleuronectiformes 255 632a 633 632c 632b 635a 634a 635b 634b 636a 637 636b Figs. 632-635: Rhombosolea plebeia (RICHARDSON 1843) – 10 × Figs. 636-637: Rhombosolea leparina GÜNTHER 1862 – 10 × NORMAN (1934) these are the expanded hypocoracoids, the loss of the pectoral fins on the blind side and the reduced number of 4 rays of the pectoral fin on the eyed side (except for Plagiopsetta). Several species are specially adapted to Piscium Catalogus, Part Otolithi piscium, Vol. 2 living in a reefoidal environment. In recent literature the fishes of this group are placed in a family of its own – Samaridae (CHAPLEAU 1993 and NELSON 1994) – but are kept here in subfamily ranking provisionally until the interrelationship 256 638c 638a 638b 639c 639a 639b 640 641 642b 643b 642a 643a Figs. 638-643: Rhombosolea tapirina GÜNTHER 1862 – 10 × Schwarzhans: Pleuronectiformes 257 b a c Fig. 644: Rhombosolea retiaria HUTTON 1873 – 10 × of the Pleuronectidae s.l. becomes further revealed. The otoliths of this group likewise are quite specialized. They are relatively small and thickset and show an extremely deepened sulcus with a clear ostial opening often associated with an excisura. Amongst Pleuronectiformes these are the otoliths with the deepest, v-shaped sulcus. Outline and separation of colliculi often is barely visible. They are still recognizable as pleuronectiform otoliths by the well developed and often very deep circumsulcal depression. This character also holds against them representing a plesiomorphic otolith morphology which might be suggested by the other features. In fact, the deep sulcus and the clear ostial opening may very well be a secondary specialized development which could have evolved from similar morphologies as found in the Verasper and the Microstomus-Pleuronichthys Groups. It must be noted that at least the species of the genera Plagiopsetta and Samaris contain two distinct morphologies which in the following text will be termed morphology A and B. Whether Samariscus and Azygopus show a similar phenomenon is not as yet known. Also it is not yet known what may be the cause for the presence of these two distinct morphologies. Recently, a similar phenomenon has been reported from certain ophidiiform genera, where it correlates with sexual dimorphism (SCHWARZHANS, 1994). So far, sexual dimorphism in otoliths is extremely rare. Although fishes of the order Pleuronectiformes exhibit a wide spectrum of sexual dimorphism both in character an intensity, there is no proof so far that this finds its reflection in otolith morphology as well (for further discussion see also chapter 6.5). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Plagiopsetta FRANZ 1910 Type-species: Plagiopsetta glossa FRANZ 1910 Diagnosis: Small, thickset, elongate otoliths; ventral and dorsal rim very shallow, gently curving, dorsal rim without conspicuous angles, posterior tip pointed, usually ventrally projecting, anterior tip rather blunt, with a short, massive rostrum and a distinct excisura. Index l:h 1.45 to 2.00. Otolith size not exceeding 3 mm at most. Ostium slightly wider than cauda and not much longer. Differentiation of ostium and cauda very feeble due to poor definition of outline of colliculi. Sulcus very deep, v-shaped. Ostium clearly opening anteriorly; excisura present. Cauda terminating at moderate distance from the posterior tip of the otolith. Circumsulcal depression well developed, narrow, rather deep. Inner face rather flat to slightly convex, not smooth; outer face slightly convex or flat and smooth. Rims smooth and thickset. Measurements: glossa glossa glossa glossa (A, left) (A, right) (B, left) (B, right) l:h 1.50 1.45 1.70 2.00 h:t 1.8 2.8 1.9 2.8 ol:cl about 1.7 about 2.0 about 1.4 about 1.8 oh:ch 1.2 1.1 1.0 1.3 con.i about 3 about 3 about 5 about 5 Side dimorphism: Otoliths of the eyed side are consistently much more thin than those of the blind side. Minor differences may also exist in other otolith and sulcus proportions. Morphology types: The two morphology types found in Plagiopsetta certainly would have been attributed to separate species when studied with isolated otoliths alone. 258 645a 645c 645b 647a 646a 646b 647c 647b 648a 648b Figs. 645-648: Plagiopsetta glossa FRANZ 1910; figs. 645-646 morphotype A, figs. 647-648 morphotype B – 25 × Morphology A (figs. 645-646) shows rather compressed otoliths with a comparatively short sulcus and a more strongly convex inner face. Morphology B (figs. 647-648) contains much more elongate otoliths with perfectly smooth rims and a more flat inner face. Discussion: Otoliths of the genus Plagiopsetta closely resemble those of the related genera Samaris and Samariscus. Species and distribution: Plagiopsetta glossa is a monospecific genus with P. glossa restricted to the waters around Japan. Plagiopsetta glossa FRANZ 1910 Figs. 645-648 Investigated otoliths: 4 otoliths (left and right) from off Kochi, Japan, ZMH Ot. 29.1.1995.30-33 (leg. Sasaki; fishes now in BMNH coll.). Distribution: Japan. Samaris GRAY 1831 Type-species: Samaris cristatus GRAY 1831 Diagnosis: Small, thickset, elongate otoliths; ventral and dorsal rim very shallow, gently curving, dorsal rim sometimes with postdorsal angle and predorsal projection, posterior tip rounded Schwarzhans: Pleuronectiformes 259 or blunt, anterior tip rather blunt, with a short, massive, sometimes pointed rostrum and usually distinct excisura. Index l:h 1.55 to 1.65. Otolith size not exceeding 3 mm at most. Ostium slightly wider than cauda and not much longer. Differentiation of ostium and cauda very feeble due to poor definition of outline of colliculi. Sulcus very deep, v-shaped. Ostium clearly opening anteriorly; excisura present. Cauda terminating at moderate distance from the posterior tip of the otolith. Circumsulcal depression well developed, narrow, very deep. Inner face slightly convex, not smooth; outer face slightly convex or flat and rather smooth. Rims smooth or slightly undulating, thickset. Measurements: cristatus cristatus cristatus cristatus †validus (A, left) (A, right) (B, left) (B, right) l:h 1.55 1.65 1.60 1.60 1.70 h:t 2.1 2.4 1.8 2.2 2.0 ol:cl about 1.4 about 1.6 about 1.5 about 1.5 about 1.8 oh:ch 1.0 1.0 1.1 1.1 1.1 con.i 2.5 3.0 2.8 3.0 2.5 Side dimorphism: Less well developed than in the genus Plagiopsetta. Still otoliths from the eyed side are slightly thinner and their inner face slightly more convex than those of the blind side. QUERO, HENSLEY & MAUGE (1989), however, two additional species are listed – S. macrolepis and S. costae. In addition the fossil species S. validus is here described from the Lower Pliocene of New Zealand. Samaris cristatus GRAY 1831 Figs. 649-652 ?syn. syn. syn. ?syn. Arnoglossus cacatuae OGILBY 1910 Samaris ornatus VON BONDE 1922 Samaris delagoensis VON BONDE 1925 Samaris macrolepis NORMAN 1927 Investigated otoliths: 8 otoliths, 6 (left and right) from Hongkong, IRSNB (coll. Nolf, leg. Stinton), 1 (right side) from the Java Sea, BMNH 1931.4.23.28, 1 (left side) from Hinan, China, SMF. Distribution: From South Africa throughout the Indian Ocean, to the Chinese seas, Japan, Indonesia and Queensland. Samaris validus n.sp. Fig. 653 Morphology types: The two morphology types found in Samaris certainly would have been attributed to separate species when studied with isolated otoliths alone. Morphology A (figs. 649-650) shows otoliths with a flat, horizontal dorsal rim, a pronounced postdorsal angle, a blunt posterior tip and a rather distinct and pointed rostrum. Morphology B (figs. 651-652) is characterized by more ovally shaped otoliths with a gently curving dorsal rim including a broad predorsal projection and a rounded posterior tip. Also the rostrum is shorter and blunt or rounded. Name: validus (lat.) = valid, referring to first fossil record of this group. Holotype (and unique specimen): Fig. 653, BSP 1984 X 116. Type locality: Martinborough, New Zealand northern Island. Age: Wanganuian, Lower Pliocene. Discussion: Otoliths of the genus Samaris closely resemble those of the related genera Plagiopsetta and Samariscus. Those of Samaris are the largest in size and with a rather characteristic outline in morpho-type A. Description: Outline: Otolith about 3.5 mm long, almost rectangular in outline except for the strongly protruding rostrum. Ventral and dorsal rims flat, practically horizontal and parallel, posterior rim vertically cut. Excisura broad and deep, antirostrum small. Index l:h 1.7. Inner face: Moderately convex, not smooth. Sulcus long, deep, moderately wide, anteriorly open. Colliculi indistinct, ostium somewhat longer than cauda. Circumsulcal depression well developed, wide and rather deep. Species and distribution: According to HEEMSTRA ( 1986) probably a monospecific genus (also indicated by NORMAN, 1934, who noted 5 nominal species) with S. cristatus widely distributed in the Indo-Pacific. In a recent publication by Piscium Catalogus, Part Otolithi piscium, Vol. 2 Diagnosis: Moderately elongate, thickset otoliths with flat dorsal and ventral rims and prominent rostrum. Sulcus deep, anteriorly opening, with distinct excisura. Circumsulcal depression well developed, rather wide and deep. 260 650a 649c 649a 649b 650b 651c 651a 652a 652b 649b 653d 653a 653b 653e 653c Figs. 649-652: Samaris cristatus GRAY 1831; figs. 649-650 morphotype A, figs. 651-652 morphotype B – 15 × Fig. 653: Samaris verus n.sp. – 15 × Other views: Otolith compact and thickset, with smooth and not very sharp rims. Outer face rather flat and smooth. Discussion: This otolith is slightly larger than those of the recent S. cristatus, possibly indicating that the fossil species was growing to larger sizes than the recent one. Although in general very similar to S. cristatus, S. validus differs in the nearly straight ventral rim and the long and massive rostrum. It probably represents morphotype A. The unique holotype is very well preserved and represents the first record of the genus from New Zealand. Schwarzhans: Pleuronectiformes 261 Samariscus GILBERT 1905 Type-species: Samariscus corallinus GILBERT 1905 Diagnosis: Small, thickset, moderately elongate otoliths; ventral and dorsal rims gently curving, smooth or undulating, posterior tip pointed or rounded, anterior tip rather blunt, with a short, massive rostrum and a more or less distinct excisura. Index l:h 1.25 to 1.75. Otolith size not exceeding 2.5 mm at most. Otoliths smaller than 1 to 1.5 mm probably not diagnostically mature. Ostium slightly wider than cauda and not much longer. Differentiation of ostium and cauda very feeble due to poor definition of outline of colliculi. Sulcus very deep, v-shaped. Ostium clearly opening anteriorly; excisura present. Cauda terminating at moderate distance from the posterior tip of the otolith. Circumsulcal depression well developed, narrow, rather deep to very deep. Inner face flat to slightly convex, not smooth; outer face slightly to strongly convex and smooth. Rims thickset. l:h h:t ol:cl oh:ch 1.30-1.50 2.5-3.0 1.5-2.0 1.0-1.2 1.40 2.5 1.6 1.2 1.75 1.5 about 1.5 nm 1.25-1.30 2.2 about 2.0 1.0 con.i about 4 about 4 about 4 about 5 Side dimorphism: Judging from the otoliths of S. japonicus the degree of side dimorphism is moderate. Otoliths of the eyed side are more regularly rounded in outline, slightly more thin with a slightly more convex inner face, and also the excisura is usually deeper. Ontogeny and variability: The otoliths of S. triocellatus are less than 1 mm long and were obtained from a very small fish. They are probably subadult and in many ways are quite generalized in appearance. Sulcus and circumsulcal area are not very deep as yet. Its low index l:h may also reflect an early ontogenetic stage. Otherwise the otolith is relatively thickset. A series of otoliths obtained from S. japonicus exhibit a moderate degree of variability, mainly restricted to details of the outline, particularly concerning the expression of the dorsal rim and the rostrum. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Closely related to Samaris and Plagiopsetta (see respective entries). Species and distribution: About 17 species (according to QUERO; HENSLEY & MAUGE, 1989) from the tropical and subtropical waters of the Indo-West-Pacific – S. asanoi, S. corallinus, S. desoutterae, S. fasciatus, S. filipectoralis, S. huysmani, S. inornatus, S. japonicus, S. latus, S. longimanus, S. luzonensis, S. macrognathus, S. maculatus, S. nielseni, S. sunieri, S. triocellatus and S. xenicus. Habitat of these fishes is often associated with reefs or near reef environments, which is rather untypical for Pleuronectiform fishes. Samariscus japonicus KAMOHARA 1936 Figs. 654-659 Measurements: japonicus sunieri huysmani triocellatus Morphology types: The only species of which a larger series of otoliths is available is S. japonicus. There, no distinction in two otolith morpho-types can be observed as this is the case in Samaris and Plagiopsetta. However, this could still be purely accidental. Investigated otoliths: 8 otoliths (left and right) from off Kochi, Japan, ZMH Ot. 29.1.1995.34-41 (leg. Sasaki). Discussion: Similar to S. sunieri, but otoliths of that species have a shallower dorsal rim and a deeper ventral rim (although resulting index l:h is the same). Distribution: Chiefly off Japan. Samariscus sunieri WEBER & BEAUFORT 1929 Fig. 660 Investigated otoliths: 1 otolith (left side) from St. Nikolaas Bay, Bali, BMNH 1933.2.18.17 (paratype). Discussion: Similar to S. japonicus (see respective entry). Distribution: Chiefly around Bali, Indonesia. 262 654a 655a 654c 655b 655c 654b 656 658 657 659 Figs. 654-659: Samariscus japonicus KAMOHARA 1936 – 25 × Samariscus huysmani WEBER 1913 Fig. 661 Samariscus triocellatus WOODS 1984 Figs. 662-663 Investigated otoliths: 1 otolith (left side) from Indonesia, 08°50’S/114°14’E, BMNH 1984.1.1.108. Investigated otoliths: 2 otoliths (left and right) from the Eniwetok atoll, Marshall Islands, SMF 20184. Discussion: This otolith is readily recognized by its smooth and gently and regularly curving dorsal and ventral rims, the symmetrically pointed posterior and anterior (rostrum) tips, and the very thickset appearance. If Samariscus species also include two morphotypes as observed in Samaris and Plagiopsetta this otolith would become the only candidate for a morpho-type B of all the Samariscus otoliths investigated. Discussion: These otoliths are very small (about 0.6 mm long) and originate from a small and possibly subadult fish. They are certainly not diagnostically mature. Larger specimens have been recently figured by SMALE et al. (1995). They are also compressed, resembling in proportions those of S. japonicus but show a rather narrow sulcus and a very sharpely pointed rostrum. Distribution: Gulf of Martaban and Java Sea. Distribution: Marshall Islands, Micronesia. Schwarzhans: Pleuronectiformes 263 660b 660a 660c 616c 661a 616d 661b 662a 662b 662c 663 Fig. 660: Samariscus suineri WEBER & BEAUFORT 1929 – 25 × Fig. 661: Samariscus huysmani WEBER 1913 – 25 × Figs. 662-663: Samariscus triocellatus WOODS 1984 – 25 × Azygopus NORMAN 1926 Type-species: Azygopus pinnifasciatus NORMAN 1926 Diagnosis: Small, thickset, rather compressed otoliths; ventral rim shallow, gently curving, dorsal rim with prominent mediodorsal angles, posterior tip pointed, ventrally projecting, anterior tip with a short, massive, but pointed rostrum, situated inframedianly, a distinct excisura, and a rather sharp and long antirostrum. Index l:h 1.3. Otolith size not exceeding 3 mm at most. Ostium about as wide as cauda and not much longer. Differentiation of ostium and cauda very feeble due to poor definition of outline of colliculi. Sulcus very deep, v-shaped. Ostium clearly opening anteriorly. Cauda terminating at moderate distance from the posterior tip of the otolith. Circumsulcal depression well developed, narrow, rather deep. Inner face rather flat, not smooth; outer face convex and smooth. Rims smooth and moderately thickset. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Measurements: pinnifasciatus l:h 1.30 h:t 2.2-2.5 ol:cl 1.3-1.4 oh:ch 1.0 con.o 2.5-3.0 Side dimorphism: Not apparent. Discussion: Otoliths of the genus Azygopus resemble those of the other three genera in the Samaris Group in all principal aspects, such as habitus and sulcus morphology. This is also the reason why I have placed Azygopus in this group. The fish itself, however, does not show all the specialized characters observed in the three other genera. But in Plagiopsetta for instance the number of rays in the pelvic fins also is not reduced. Possibly Plagiopsetta and also Azygopus represent more plesiomorphic genera in this group. Species and distribution: Azygopus is a monospecific genus with A. pinnifasciatus restricted to the temperate waters of southern Australia and New Zealand. 264 664a 664c 665a 665c 665b 664b Figs. 664-665: Azygopus pinnifasciatus NORMAN 1926 – 15 × Azygopus pinnifasciatus NORMAN 1926 Figs. 664-665 Investigated otoliths: 2 otoliths (left and right) from New Zealand, AUG-V 291 (coll. Grenfell). Distribution: Southern Australia and New Zealand. Poecilopsettinae 7.7.11 Marleyella Group Genera: A single genus – Marleyella – from the Indian Ocean. Definition and relationship: The otoliths of the genus Marleyella exhibit a rather plesiomorphic character status, somewhat resembling Citharidae otoliths. This is expressed by the pentagonal outline of the otolith, the anterior opening of the sulcus and the low index ol:cl. On the other hand, and different from Citharidae, the circumsulcal depression is already complete and well developed. It is assumed that the Marleyella Group represents an early phylogenetical spin-off from the main Pleuronectid stem or even a pre-pleuronectid stage and has given raise to the Poecilopsetta Group (see respective entry). NORMAN (1934), NELSON (1994) and others related Marleyella closely to Poecilopsetta and had the two groups as defined here by otoliths in a separate subfamily Poecilopsettinae. CHAPLEAU (1993) even suggested family ranking. Marleyella FOWLER 1925 Type-species: Poecilopsetta bicolorata BONDE 1922 VON Diagnosis: Thin, moderately elongate otoliths; ventral rim with distinct medioventral angle, dorsal rim rounded with postdorsal angle and pronounced mediodorsal projection, anterior and posterior tips pointed inframedianly. Index l:h 1.5 to 1.6. Otolith size not much exceeding 3.5 mm. Ostium slightly wider than cauda and not much longer. Index ol:cl 1.4 to 1.5. Ostium anteriorly opened, only very slightly reduced. Cauda terminating at moderate distance from the posterior tip of the otolith. Sulcus slightly deepened. Colliculi well separated. Circumsulcal depression posteriorly well developed, moderately wide and deepened. Inner face slightly convex and rather smooth; outer face flat and smooth. Rims sharp. Measurements: bicolorata l:h 1.50-1.60 h:t 3.4 ol:cl oh:ch con.i 1.40-1.50 1.35-1.65 about 5 Side dimorphism: No data. Discussion: See entry to group. Species and distribution: Two species – M. bicolorata and M. maldivensis – from the Indian Ocean. Marleyella bicolorata (VON BONDE 1922) Figs. 666-667 Investigated otoliths: 2 otoliths (left side) from off Natal, South Africa, ZMH Ot. 29.1.1995.42 (leg. BMNH 1922.3.27.5-6) and BMNH 1922.3.27.5-6 (syntypes). Schwarzhans: Pleuronectiformes 265 667a 667c 666 667b Figs. 666-667: Marleyella bicolorata (VON BONDE 1922) – 15 × Distribution: Indian Ocean, chiefly South and East Africa. 7.7.12 Poecilopsetta Group Genera: Two genera – Poecilopsetta and Nematops – in relatively deep water in tropical and subtropical seas. Definition and relationship: The two genera of the Poecilopsetta Group no doubt are closely related to Marleyella and probably have derived from it. Together they form the subfamily Poecilopsettinae (see also respective entry). Their otoliths are easily recognized by their almost circular outline (except for the short and massive rostrum) and the clear cut sulcus with its rather high index ol:cl and the ostial opening. In habitus they can be confused with similar looking otoliths of certain Bothid groups, such as the Arnoglossus or the Monolene-Laeops Group. Poecilopsetta GÜNTHER 1880 Type-species: Poecilopsetta colorata GÜNTHER 1880 syn. Boopsetta ALCOCK 1896 (type-species: Boopsetta umbrarum, syn. P. praelongo) syn. Alaeops JORDAN & STARKS 1904 (type-species: Alaeops plinthus) syn. Paralimanda BREDER 1927 (type-species: Paralimanda inermis) Diagnosis: Moderately thickset, almost completely round otoliths; only the massive but short rostrum sticking out from it, all rims more or less Piscium Catalogus, Part Otolithi piscium, Vol. 2 gently and regularly curving, sometimes undulating or with a rounded postdorsal angle. Index l:h 1.0 to 1.3. Otolith size not much exceeding 3 mm. Otoliths below 1.5 mm probably not diagnostically mature. Ostium wider than cauda and usually much longer. Index ol:cl 1.4 to 2.3. Ostium anteriorly open or just slightly reduced. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus deepened, at least the colliculi which are well separated. Circumsulcal depression well developed, wide and somewhat deepened. Inner face rather flat, not very smooth; outer face flat to slightly convex, and smooth. Rims moderately sharp to thickset. Measurements: plinthus praelongo beanii albomaculatus zanzibarensis natalensis l:h h:t ol:cl 1.25-1.30 2.8-3.1 1.40-1.80 1.00-1.10 3.0 2.00-2.30 1.10 nm 2.00 1.15 2.5 2.30 1.10-1.15 2.7-3.0 1.65-1.85 1.10-1.15 3.0 1.80 oh:ch 1.2-1.3 1.2 1.2 1.4 1.2-1.3 1.3-1.4 con.i 5-7 about 6 nm 3.5 4-5 3.5 Side dimorphism: Not very strongly developed. Otoliths of the eyed side tend to develop a more pronounced postdorsal angle, a more clear cut ostial opening and sometimes also less well separated colliculi. Variability: Variability seems to be rather limited in most cases. The characters most commonly affected are details of the outline. Unfortunately, this also one of the few features useful to distinguish amongst the various species, which sometimes may become very difficult or even impossible with otoliths alone. 266 670a 668a 669 670b 668b 671c 672 671a 671 674 673a 673b 673c Figs. 668-670: Poecilopsetta plinthus (JORDAN & STARKS 1904) – 15 × Figs. 671-672: Poecilopsetta praelongo ALCOCK 1894 – 15 × Fig. 673: Poecilopsetta albomaculata NORMAN 1938 – 15 × Fig. 674: Poecilopsetta beani (GOODE 1881) – 15 × Discussion: Closely related to Nematops which may have just slightly more regularly rounded and fragrant otoliths as compared to Poecilopset- ta. Differentiation of the various species within the genus Poecilopsetta often is very difficult by means of otoliths alone. Schwarzhans: Pleuronectiformes 267 Species and distribution: About 13 species from the deeper tropical and subtropical seas – P. beanii, P. inermis and P. megalepis from the tropical West Atlantic, P. hawaiiensis from Hawaii, P. plinthus from Japan, P. albomaculata, P. albomarginata, P. colorata, P. natalensis, P. normani, P. praelongo, P. vaynei and P. zanzibarensis from the Indian Ocean. and the very narrow sulcus. It closely resembles P. praelongo. Distribution: Gulf of Mexico and coast of New England. Poecilopsetta albomaculata NORMAN 1938 Fig. 673 Poecilopsetta plinthus (JORDAN & STARKS 1904) Figs. 668-670 Investigated otoliths: 3 otoliths, 1 (left side, fig. ) from the Suruga Bay, Japan, BMNH 1931.8.19.8, 2 (left and right, figs.) from Japan, coll. Ohe No 851227-47. Discussion: The otoliths of P. plinthus are somewhat less compressed than those of most other species of the genus and are also characterized by their relatively low index ol:cl. Investigated otoliths: 1 otolith (left side) from the Maldives Islands, BMNH 1939.5.24.1774-6 (paratype). Discussion: Rather compact and thickset otolith with a strongly widened ostium and a nearly straight anterior part of the ventral rim. Distribution: Maldives Islands. Poecilopsetta zanzibarensis NORMAN 1938 Figs. 675-678 Distribution: Coasts of Japan. Poecilopsetta praelongo ALCOCK 1894 Figs. 671-672 syn. Boopsetta umbrarum ALCOCK 1896 Investigated otoliths: 2 otoliths (left and right) from the Deutsche Tiefsee-Expedition 1898/99 Stat. 209, ZMH Ot. 30.1.1995.1-2 (leg. ZMH 21160). Investigated otoliths: 4 otoliths (3 left and 1 right) from Zanzibar, ZMH Ot. 30.1.1995.3-5 (leg. BMNH 1939.5.24.1777-84) and BMNH 1939.5.24.1777-84 (syntypes). Discussion: Like P. praelongo a species with a rather strong postdorsal angle and a more pointed rostrum. Unlike P. praelongo the index ol:cl is rather small. Distribution: East Africa. Discussion: Otoliths of P. praelongo are probably the most compressed to be found in this genus so far, together with P. beanii. Also characteristic is the very small cauda. Distribution: Bay of Bengal and Andaman Sea. Poecilopsetta beanii (GOODE 1881) Fig. 674 Investigated otoliths: 1 otolith (left side), 28°41’N/86°07’W, BMNH 1931.8.19.10. Discussion: The only investigated otolith is slightly eroded by formalin. Nevertheless, it is characterized by the very compressed appearance Piscium Catalogus, Part Otolithi piscium, Vol. 2 Poecilopsetta natalensis NORMAN 1931 Figs. 679-680 Investigated otoliths: 2 otoliths (left and right) from off South Africa, Vityaz Stat. 2644, ZMH Ot. 30.1.1995.6-7 (leg. ZMUC; specimens obtained from a unlabeled fish in jar together with Paracitharus macrolepis). Discussion: Rather thin otolith with a wide ostium and a high index ol:cl. Similar to P. zanzibarensis and P. albomaculatus. Distribution: South Africa, off Natal and Delagoa Bay. 268 675c 677 675a 675b 676b 676a 678 679a 680 679b Figs. 675-678: Poecilopsetta zanzibarensis NORMAN 1938 – 15 × Figs. 679-680: Poecilopsetta natalensis NORMAN 1931 – 15 × Nematops GÜNTHER 1880 Type-species: Nematops microstoma GÜNTHER 1880 Inner face rather flat and rather smooth; outer face slightly convex, and smooth. Rims moderately sharp. Diagnosis: Moderately thin, almost completely round otoliths; only the short and not very massive rostrum sticking out from it, all rims more or less gently curving, sometimes undulating. Index l:h about 1.2. Otolith size probably not exceeding 3 mm. Ostium not wider than cauda but considerably longer. Index ol:cl about 1.6. Ostium anteriorly open. Cauda short, terminating at some distance from the posterior tip of the otolith. Sulcus slightly deepened, at least the colliculi which are rather well separated. Circumsulcal depression well developed, wide and not very deep. Measurements: grandisquama l:h 1.20 h:t 3.0 ol:cl 1.60 oh:ch 1.0 con.i 4.5 Side dimorphism: No data. Discussion: The fishes of the genus Nematops are very rare. The otolith of a single specimen investigated does not differ greatly from otoliths of the closely related genus Poecilopsetta. It is thinner than most Poecilopsetta otoliths and the narrow sulcus resembles such species as Poecilopsetta beanii. Schwarzhans: Pleuronectiformes 269 Species and distribution: Four species from the deeper water of the Indo-Australian Archipelago – N. chui, N. grandisquama, N. macrochirus and M. microstoma. Nematops grandisquama WEBER & BEAUFORT 1929 Fig. 681 Investigated otoliths: 1 otolith (left side) from St. Nikolaas Bay, Bali, BMNH 1933.2.18.16 (paratype). Distribution: Chiefly coasts of Bali. 7.8 Soleidae Genera: Unlike Pleuronectoidei and part of Cynoglossidae the Soleidae have never been subject to a comprehensive revision. Soleid genera (and species) are often poorly defined and in need for a general revision. Many genera of doubtful definition have been introduced, mostly through the work of CHABANAUD (div.). I have adopted here a more generalized attitude, following the view expressed by HEEMSTRA & GON (1981), I have lumped a number of nominally valid genera together. Thus the family Soleidae as presented here contains 37 extant genera plus 3 fossil otolith-based genera. In alphabetical order they are: Achiropsis, Achirus, Aesopia, Anisochirus, Apionichthys, Aseraggodes, Austroglossus, Bathysolea, Brachirus, Catathyridium, Dageichthys, Dexillichthys, Dicologlossa, Gymnachirus, Heterobuglossus, Heteromycteris, Hypoclinemus, Microbuglossus, Microchirus, Monochirus, Nodogymnus, Parachirus, Pardachirus, Peltorhamphus, Phyllichthys, Pnictes, Pseudaesopia, Quenselia, Rendahlia, Solea, Soleichthys, Soleonasus, Synaptura, Trinectes, Typhlachirus, Vanstraelenia, Zebrias – and the fossil Granulithus, Praearchirolithus, Pseudopardachirolithus. Rhinosolea FOWLER 1946 was based on a single anomalous specimen (SASAKI, written communication) and is here not regarded as a valid genus. Definition and relationship: Soleidae are the amalgamation of all right eyed Soleoidei (the Cynoglossidae representing the left eyed Soleoidei). In past literature they have been subdivided to various degrees into subfamilies. This was carried furthest by CHABANAUD (1939), who diPiscium Catalogus, Part Otolithi piscium, Vol. 2 a b Fig. 681: Nematops grandisquama WEBER & BEAUFORT 1929 – 15 × vided the Soleidae into Achiridae and Soleidae. In Achiridae he recognized the Achirinae and the Apionichthyinae and in Soleidae, the Soleinae, Pardachirinae and Heteromycterinae. The limits of the five subfamilies of CHABANAUD (1939) correspond well to the otolith grouping as presented here, but I have subdivided the Soleinae in four genus groups – the Solea, Synaptura, Brachirus and Zebrias Groups. Separation of Achiridae from Soleidae again was promoted in the phylogenetical analysis of CHAPLEAU (1993) with the argument that the Achiridae would represent the plesiomorphic sistergroup of the remaining Soleoidei (see also NELSON, 1994). I have adhered here to the more traditional view and keep Achiridae as subfamily Achirinae in the Soleidae (see NELSON 1984). Otoliths of the Soleidae typically are compressed with a rather regular round or oval shape, a somewhat reduced sulcus opening and a tendency towards a shallow sulcus and fused or at least poorly defined colliculi. Often their inner face is quite convex and smooth which can best be shown in lateral views. Thus soleid otoliths in most instances are quite easily recognized and differentiated from those of other pleuronectiform families. Soleid otolith morphologies can readily be differentiated into three main groups, to which I have applied subfamily ranking. These are the Achirinae (Achirus and Apionichthys Groups), the Soleinae (Solea, Synaptura, Brachirus and Zebrias Groups) and the Pardachirinae (Pardachirus and Heteromycteris Groups, the latter including the genus Peltorhamphus from NORMAN’s (1934) Rhombosoleinae, a subfamily of the Pleuronectidae). Otoliths of the Achirinae are characterized by a rather elongate, regularly oval outline and a long cauda. The cauda is in fact almost as long as 270 the ostium in most genera. This must be regarded as a plesiomorphic feature which supports CHAPLEAU’s (1993) phylogenetical analysis. The otoliths of the Soleinae are similar in appearance, but usually somewhat more compressed and with a reduced cauda. Also in most instances their inner face is distinctly convex. Finally, otoliths of the Pardachirinae are usually even more compressed, often with an index l:h of about 1.0 or less and with a short cauda. The sulcus is shallow as is the circumsulcal depression giving the inner face, which is often markedly convex, a very smooth appearance. In some genera a certain tendency toward fused colliculi and a widened cauda can be observed. These otoliths (specially from the Heteromycteris Group) closely resemble cynoglossid otoliths, as do the fishes of the two groups themselves (e.g. loss of the pectoral fins; incipiently hooked mouth). Indeed it seems very likely to me that the Cynoglossidae evolved from near the Pardachirinae. NORMAN (1934) noted that some members of the pleuronectid subfamily Rhombosoleinae resemble Soleids but concluded that this was mere analogy. Otolith analysis shows that the Rhombosoleinae, as then understood, very probably do not form a natural assemblage and it seems possible that several of ist genera do not belong to the family Pleuronectidae at all (see entries to chapters 5.3.2., the Ammotretis Group, Pleuronectidae and the Samaris, Pelotretis and Rhombosolea Groups). However, in regard to the non-relationship of the Rhombosoleinae to the Soleidae NORMAN was essentially correct, except in respect of the genus Peltorhamphus. Although my conclusions are entirely based on otolith analysis I feel very strongly convinced that Peltorhamphus belongs with the Soleidae in the vicinity of Heteromycteris and Rendahlia of the Heteromycteris Group. In the fossil record soleid otoliths are relatively well known from the Oligocene onward. Earliest findings are from the Eocene of France and represent the subfamily Pardachirinae. This indicates that the origin of the Soleidae occured relatively early in the history of the Pleuronectiformes. Even more, the subdivision of the Soleidae into the three main branches was already established at that time, with the Pardachirinae probably representing the most apomorphic lin- eage. This also indicates that the dichotomy that gave raise to the Soleidae may well pre-date, for instance, the splitting of the main pleuronectoid stem into Scophthalmidae, Bothidae and Pleuronectidae, and must have occured at about the citharid-brachypleurid level. In this respect it is of interest to note the overall resemblance of brachypleurid otoliths with soleid otoliths (see respective entries). Distribution: Soleidae are widely distributed throughout the shallow warm seas of the world oceans and several species ascent into rivers or are entirely adapted to fresh water. The family is most speciose and diverse in the tropics. Achiriniae are restricted to the Americas and are also commonly found in freshwater. Soleinae and Pardachirinae, on the other hand, are exclusively old world subfamilies, the Pardachirinae with very few exceptions being confined to the IndoPacific. Achirinae 7.8.1 Achirus Group Genera: Trinectes, Achirus, Catathyridium, Hypoclinemus, Gymnachirus, Nodogymnus. There are few undeterminable fossil otolith records from the Miocene of Trinidad and the Dominican Republic. Definition and relationship: Otoliths of the Achirus Group probably represent the most plesiomorphic ones to be found in the Soleidae. Outline is rather regularly rounded to oval. The otoliths are relatively robust with only a moderately convex inner face. Most important though is the plesiomorphic pattern of the sulcus. The sulcus is somewhat deepened and the cauda is not much shorter than the ostium. In few genera (Gymnachirus, Nodogymnus), which form a small subgroup in this group, the sulcus is considerably deepened and the colliculi are completely fused, thus resembling certain morphologies found in the Zebrias Group (see respective entry). The genera of the Apionichthys Group are considered to be closely related, but differ in the already much reduced cauda. Schwarzhans: Pleuronectiformes 271 683a 682a 682c 683b 682b Figs. 682-683: Trinectes maculatus (BLOCH & SCHNEIDER 1801) – 15 × Trinectes RAFINESQUE 1832 Type-species: Trinectes scabra RAFINESQUE 1832 (syn. T. maculatus) Diagnosis: Moderately thickset, ovale otoliths; ventral rim shallow and gently curving, dorsal rim likewise but somewhat more irregularly, anterior rim rounded, posterior rim cut to slightly concave, usually with prominent angles where it meets the dorsal and ventral rims. Index l:h 1.15 to 1.35. Otolith size up to 4.5 mm. Sulcus deepened, rather wide, centrally positioned, terminating with rounded tips at some distance from anterior and posterior rims. Ostium not or just slightly wider than cauda and not much longer. Dorsal and ventral depressions rather wide, moderately deep and well connected around the cauda to form a circumsulcal depression. Inner face rather flat, not very smooth, sometimes with irregular marginal ornamentation; outer face flat, sometimes irregularly ornamented. Rims rather thickset, sometimes irregularly crenulated. Measurements: maculatus paulistanus fonsecensis l:h h:t ol:cl 1.15-1.35 2.4-3.1 1.05-1.10 1.15-1.25 2.9 1.25-1.40 nm nm 1.45 oh:ch 1.0 1.2-1.3 1.0 con.i 3.5 3.0-3.2 2.8 Side dimorphism: Not apparent. Variability: The variability of otoliths in the species of this genus seems to be rather limited. As the figures of T. maculatus show it mostly concerns the index l:h. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Very similar to Achirus of which Trinectes sometimes is regarded as a subgenus. Trinectes otoliths seem to generally show a flatter inner face, a deeper circumsulcal depression and a lower index ol:cl. Species and distribution: CHABANAUD (1939) lists 7 nominally valid species – T. maculatus, T. paulistanus, T. inscriptus, T. microphthalmus from the Atlantic coast of America and T. fonsecensis, T. fluviatilis and T. fimbriatus from the Pacific coast of America. Trinectes maculatus (BLOCH & SCHNEIDER 1801) Figs. 682-683 syn. syn. syn. syn. syn. syn. Achirus fasciatus LACEPEDE 1803 Pleuronectes mollis MITCHILL 1815 Pleuronectes apoda MITCHILL 1815 Trinectes scabra RAFINESQUE 1832 Solea browni GÜNTHER 1862 Achirus comifer JORDAN & GILBERT 1884 Investigated otoliths: 2 otoliths (left side) from off New York, USA, ZMH Ot. 12.3.1995.1 (leg. BMNH 1982.11.10.21-26) and BMNH 1982.11. 10.21-26. Discussion: Otoliths of T. maculatus are recognized by their very low index ol:cl and oh:ch and the rather wide sulcus. Distribution: Atlantic coast of North America from Massachusetts to the Caribbean. 272 685a 684a 684c 684b 686c 685b 686b 686a Figs. 684-685: Trinectes paulistanus (RIBEIRO 1915) – 15 × Fig. 686: Trinectes fonsecensis (GÜNTHER 1862) – 10 × Trinectes paulistanus (RIBEIRO 1915) Figs. 684-685 Distribution: Pacific coast of America in the Gulf of Panama. syn. Achirus austrinus CHABANAUD 1928 Investigated otoliths: 2 otoliths (left and right) from British Guiana, ZMH Ot. 12.3.1995.2 (leg. BMNH 1950.5.15.47-49) and BMNH 1950.5.15. 47-49. Discussion: Very similar to T. maculatus but with shorter and narrower cauda. Distribution: Atlantic coast of South America from the Guianas to Rio de Janeiro. Trinectes fonsecensis (GÜNTHER 1862) Figs. 686 syn. Solea panamensis STEINDACHNER 1876 syn. Solea fischeri STEINDACHNER 1879 Investigated otoliths: 1 dorsally eroded otolith from the Pacific coast of Panama, BMNH 1903.5.15.249-50. Achirus LACAPEDE 1803 Type-species: Pleuronectes achirus LINNAEUS 1758 syn. Grammichthys KAUP 1858 (type-species: Pleuronectes lineatus) syn. Baiostoma BEAN 1882 (type-species: B. brachialis, syn. A. lineatus) syn. Anathyridium CHABANAUD 1928 (typespecies: Solea gronovii, syn. Achirus achirus) Diagnosis: Moderately thickset oval to roundish otoliths; ventral rim moderately shallow to deeply and gently curving, dorsal rim shallow, often somewhat more irregular, anterior rim rounded, posterior rim broadly rounded or blunt, but not concave, usually with prominent angles where it meets the dorsal rim. Index l:h 1.05 to 1.30. Otolith size up to 4.5 mm. Sulcus somewhat deepened, not very wide, centrally positioned, terminating with rounded tips at some distance from anterior and posterior Schwarzhans: Pleuronectiformes 273 687a 687c 688 687b Figs. 687-688: Achirus achirus (LINNAEUS 1758) – 10 × rims. Ostium not or just slightly wider than cauda but somewhat longer. Dorsal and ventral depressions rather wide, not very deep and well connected around the cauda to form a circumsulcal depression. Inner face moderately convex, moderately smooth, sometimes with irregular marginal ornamentation; outer face flat to concave, sometimes irregularly ornamented. Rims moderately thickset sometimes rather sharp and irregularly crenulated. Measurements: achirus declivis mazatlanus scutum garmani l:h 1.25-1.30 1.10-1.20 1.15-1.25 1.05-1.10 1.10 h:t 3.8 3.0 3.1 3.2 3.0 ol:cl 1.20-1.40 1.15-1.30 1.50-1.80 1.35-1.45 1.25 oh:ch 1.0 0.9-1.1 1.1-1.3 1.2 1.45 con.i 3.8 2.8-3.4 3.4 2.7 2.5 Side dimorphism: Not apparent. Variability and ontogeny: The level of variability is rather restricted and so is the level of ontogenetic changes as can be seen from the figures of A. mazatlanus. The critical diagnostic size seems to be reached with 2 mm of length. Discussion: Very similar to Trinectes. Achirus otoliths usually are more compressed with a more convex inner face and a shorter cauda. Species and distribution: At least 14 nominally valid species – A. achirus, A. declivis, A. garmani, A. lorentzi, A. lineatus, A. microphthalamus, A. novae, A. opercularis, A. trichospilus, A. zebrinus from the Atlantic coast of America and A. barnharti, Piscium Catalogus, Part Otolithi piscium, Vol. 2 A. klunzingeri, A. mazatlanus, A. scutum from the Pacific coast of America. Achirus achirus (LINNAEUS 1758) Figs. 687-688 syn. Solea gronovii GÜNTHER 1862 syn. Solea indica GÜNTHER 1862 Investigated otoliths: 2 otoliths from British Guiana, ZMH Ot. 12.3.1995.3 (leg. ZMH H 871, fig. 687) and BMNH 1984.8.8.338-344 (fig. 688). Discussion: Otoliths of A. achirus is immediately differentiated from other species of the genus by its more elongate otoliths. In this respect it is more difficult to distinguish it from species of the related genera Trinectes and Catathyridium. Distribution: Tropical Atlantic coast of America. Achirus declivis CHABANAUD 1940 Figs. 689-692 Investigated otoliths: 4 otoliths (3 left, 1 right) from Trinidad, ZMH Ot.19.3.1995.1-3 (leg. BMNH 1932.5.9.20-23) and BMNH 1932.5.9.20-23. Discussion: Otoliths with the typical compressed, roundish outline to be found in this genus, but with a rather small and narrow sulcus. Distribution: Caribbean. 274 690a 689 690b 691a 691c 692 691b Figs. 689-692: Achirus declivis CHABANAUD 1940 – 15 × Achirus mazatlanus (STEINDACHNER 1869) Figs. 693-694 syn. Solea pilosa PETERS 1869 Investigated otoliths: 2 otoliths (left side) from the Mazatlan lagoon, Pacific coast of Mexico, ZMH Ot. 19.3.1995.4 (leg. BMNH 1982.8.19.230620) and BMNH 1982.8.19.2306-20). Discussion: Similar to A. declivis, but with more or less straight dorsal and posterior rims. Achirus scutum (GÜNTHER 1862) Figs. 695-696 Investigated otoliths: 2 otoliths (left and right) from the Pacific coast of Panama, ZMH Ot. 19.3.1995.5 (leg. BMNH 1930.9.2.36) and BMNH 1930.3.1995.5. Discussion: Otoliths are rather easily recognized by their more thin appearance and the wide and somewhat deepened sulcus. Distribution: Pacific coast of Panama. Distribution: Tropical coast of Pacific America. Schwarzhans: Pleuronectiformes 275 694c 694a 693 694b 695a 695c 696 695b 697b 697a Figs. 693-694: Achirus mazatlanus (STEINDACHNER 1869) – 15 × Figs. 695-696: Achirus scutum (GÜNTHER 1862) – 15 × Fig. 697: Achirus garmani JORDAN 1889 – 15 × Achirus garmani JORDAN 1889 Fig. 697 All rims are rather smooth and gently curved. Distribution: Southern coasts of Brazil. syn. Catathyridium grandiviri (CHABANAUD 1928) Investigated otoliths: 1 otolith (right side) from Rio Grande do Sul, Brazil, BMNH 85.2.3.75-76. Discussion: The sulcus is wide and rather deep as in A. scutum but the otolith is more thickset. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Catathyridium CHABANAUD 1928 Type-species: Solea jenynsi GÜNTHER 1862 Diagnosis: Moderately thickset ovale otoliths; ventral rim shallow and gently curving, dorsal rim likewise but somewhat more irregularly, 276 699 698a 698c 700 698b Figs. 698-700: Catathyridium jenynsi (GÜNTHER 1862) – 15 × anterior rim rounded, posterior rim cut or also rounded, sometimes with postdorsal angle. Index l:h 1.25 to 1.45. Otolith size up to 4 mm. Sulcus deepened, rather wide and long, centrally positioned, terminating with rounded tips not very far from anterior and posterior rims. Ostium not or just slightly wider than cauda and not much longer. Dorsal and ventral depressions rather wide, shallow and well connected around the cauda to form a circumsulcal depression. Inner face moderately convex, irregularly ornamented, particularly near the otolith margins; outer face flat, slightly and irregularly ornamented. Rims rather thin, irregularly crenulated. Measurements: jenynsi l:h 1.25-1.45 h:t 2.8 ol:cl 1.20-1.25 oh:ch 1.0-1.2 con.i 2.8 Side dimorphism: No data. Variability and ontogeny: Details of the outline and in particularly strength and nature of the marginal ornamentation seem to be quite variable. Smaller specimens of less than 2.5 mm are more compressed than those of 3 mm and more. Thus specimens below 2.5 mm may not have developed all pertinent diagnostically valid characters. Discussion: Otoliths of Catathyridium closely resemble those of the genus Achirus, in particular those of its type-species A. achirus. Characteristic is the more elongate shape and the rather long sulcus. Species and distribution: Catathyridium probably is a monospecific genus since C. grandiviri CHABANAUD 1928 may represent a synonym of Achirus garmani JORDAN 1889 (see respective entry). C. jenynsi is known from the Atlantic coast of southern America and in the La Plata and Paraguay river systems. Catathyridium jenynsi (GÜNTHER 1862) Figs. 698-700 Investigated otoliths: 3 otoliths (left side) from the Paraguay river, ZMH Ot. 19.3.1995.6-8 (leg. ZMH H878). Distribution: Atlantic coast of South America, La Plata and Paraguay rivers. Hypoclinemus CHABANAUD 1928 Type-species: Hypoclinemus paraguayensis CHABANAUD 1928 Diagnosis: Moderately thickset oval otoliths; ventral rim gently curving, smooth, dorsal rim likewise but somewhat irregularly undulating, anterior rim rounded or slightly pointed, posterior rim bluntly rounded, postdorsal angle may be present. Index l:h 1.30 to 1.45. Otolith size up to 3.5 mm. Sulcus rather deep and wide, centrally positioned, terminating with rounded tips at some distance from anterior and posterior rims. OsSchwarzhans: Pleuronectiformes 277 702a 701 702c 702b Figs. 701-702: Hypoclinemus mentalis (GÜNTHER 1862) – 15 × tium and cauda almost fused. Ostium not or just slightly wider than cauda and not much longer. Dorsal and ventral depressions rather wide, moderately deep and well connected around the cauda to form a circumsulcal depression. Inner face rather flat, smooth; outer face slightly convex, smooth. Rims rather thickset. Measurements: mentalis l:h 1.30-1.45 h:t 2.5 ol:cl 1.20-1.35 oh:ch 1.0-1.1 con.i about 4 Side dimorphism: No data. Variability: Judging from the two specimens investigated it seems that the variations are quite remarkable as far as the outline of the otoliths is concerned and the index l:h. Discussion: Otoliths of Hypoclinemus are quite easily recognized by their deep sulcus with the nearly fused colliculi. In this respect they resemble otoliths of Gymnachirus and Nodogymnus. The latter, however, are more thin with a more convex inner face, and show a thinner, anteriorly pointed sulcus with completely fused colliculi. Species and distribution: Two species along the Atlantic shores of South America entering the Amazonas and Paraguay river systems – H. mentalis and H. paraguayensis. Hypoclinemus mentalis (GÜNTHER 1862) Figs. 701-702 Investigated otoliths: 2 otoliths (left side) from the Amazonas upstream in Peru, ZMH Ot. 19.3.1995.9-10 (ZMH H879). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Atlantic coast of South America and entering into the Amazonas river system upstream to Peru. Gymnachirus KAUP 1858 Type-species: Gymnachirus nudus KAUP 1858 Diagnosis: Rather thin ovale otoliths; ventral rim shallow, posteriorly almost straight and anteriorly steeply ascending to a pointed tip, dorsal rim more gently curving somewhat irregularly undulating, with a slight concavity towards the pointed anterior tip, posterior rim cut to slightly concave, usually with prominent angles where it meets the dorsal and ventral rims. Index l:h 1.2 to 1.35. Otolith size up to 3.5 mm. Sulcus deep, rather wide, with completely fused colliculi, centrally positioned, terminating with a rounded tip at some distance from posterior rim, but anteriorly pointed and close to the anterior tip of the otolith. A small ventral indentation of the fused colliculum indicates ostium and cauda. Ostium not or just slightly wider than cauda and not much longer. Dorsal and ventral depressions rather wide, moderately deep and well connected around the cauda to form a circumsulcal depression. Inner face slightly convex, rather smooth except for the deep sulcus; outer face flat, smooth. Rims rather thin. Measurements: melas l:h 1.20-1.35 h:t 3.8 ol:cl 1.35-1.40 oh:ch nm con.i 3.5 Side dimorphism: No data. Discussion: The characteristic outline of the otoliths and the very deep sulcus with the complete- 278 ly fused colliculi readily distinguishes otoliths of the genus Gymnachirus (and those of the related genus Nodogymnus) from all other achirin genera. In this respect they do resemble certain genera of the Zebrias Group (see respective entry) but this probably represents parallel evolution or functional morphological adaption. CHABANAUD (1940, 1949) not only regarded Nodogymnus as a synonym of Gymnachirus but also suggested that the two species of Gymnachirus and the 5 nominal species of Nodogymnus (see CHABANAUD, 1939) would represent just one single species – G. nudus. Apparently, this view has not been shared in more recent literature. Knowledge of otoliths from the two nominal genera is as yet not sufficient to comment. Species and distribution: Two species – G. nudus from the Atlantic coast of South America and G. melas from the Atlantic coast of North America. Gymnachirus melas NICHOLS 1916 Figs. 703-704 Investigated otoliths: 2 otoliths (left and right) from off Georgia, USA, ZMH Ot. 9.3.1995.11-12 (leg. Fitch). Discussion: See entry to genus and to Nodogymnus texae. Distribution: Atlantic coast of North America and the Bahamas. Nodogymnus CHABANAUD 1928 Type-species: Gymnachirus fasciatus GÜNTHER 1862 Diagnosis: Rather thin otoliths with nearly rectangular outline; ventral rim shallow, undulating, posteriorly almost straight and anteriorly steeply ascending to a pointed tip, dorsal rim more gently curving and more strongly undulating, with a slight concavity towards the pointed anterior tip, posterior rim nearly vertically cut, with prominent angles where it meets the dorsal and ventral rims. Index l:h about 1.2. Otolith size probably more than 3 mm. Sulcus moderately deep, narrow, with completely fused colliculi, centrally positioned, ter- minating with a rounded tip at some distance from posterior rim, anteriorly somewhat narrowed and close to the anterior tip of the otolith. A small ventral indentation of the fused colliculum indicates ostium and cauda. Ostium just slightly wider than cauda and somewhat longer. Dorsal and ventral depressions rather wide, moderately deep and well connected around the cauda to form a circumsulcal depression. Inner face nearly flat, moderately smooth; outer face flat, slightly ornamented. Rims rather thin. Measurements: texae l:h 1.20 h:t 3.8 ol:cl 1.55-1.70 oh:ch 1.15 con.i about 4 Side dimorphism: Not apparent. Discussion: CHABANAUD (1928) suggested that the two species of Gymnachirus and the five nominal species of Nodogymnus represent but a single species – Gymnachirus nudus (see also entry to Gymnachirus and Nodogymnus texae). Species and distribution: According to CHABANAUD (1939) there are five nominal species in Nodogymnus – N. fasciatus, N. nicholsi, N. williamsoni, N. texae from the Atlantic coast of North America and N. zebrinus from the Atlantic coast of South America. Nodogymnus texae GUNTER 1936 Figs. 705-706 Investigated otoliths: 2 otoliths (left and right) from Port Aransas, Texas, ZMH Ot. 19.3.1995.13 (leg. BMNH 1948.8.6.1455-59) and BMNH 1948.8. 6.1455-59. Discussion: The two otoliths investigated from N. texae differ from those of Gymnachirus melas in the more rectangular outline, the undulating margins and the rather narrow and not so deep sulcus. Since the specimens investigated are considerably smaller than those of Gymnachirus melas it is difficult to say how much of these differences are due to allometric ontogeny (see also entry to Gymnachirus and Nodogymnus). Distribution: Coasts of Texas. Schwarzhans: Pleuronectiformes 279 703c 703a 704 703b 706c 705b 706a 705a 706b Figs. 703-704: Gymnachirus melas NICHOLS 1916 – 15 × Figs. 705-706: Nodogymnus texae GUNTER 1936 – 15 × 7.8.2 Apionichthys Group Genera: Following CHABANAUD (1939) 4 mostly monospecific genera from the Atlantic coast of South America and its rivers are placed in this group, also otoliths are only known from one of them. The 4 genera are – Apionichthys, Achiropsis, Soleonasus and Pnictes. Definition and relationship: Since CHABANAUD’s review of the Achirinae (1928) the four genera making up the Apionichthys Group are thought to be closely related to those of the Achirus Group. In 1939 CHABANAUD separated them from the Achirinae in a subfamily of there own, the Apionichthyinae in the then family Achiridae. Otoliths have only been available from one genus of these rare fishes, and any conclusions to possible relationships are difficult to draw. Nevertheless, this otolith differs from those in the Achirus Group in two main features. That is the rather short and reduced cauda and the rather strongly convex and smooth inner face with the Piscium Catalogus, Part Otolithi piscium, Vol. 2 shallow sulcus. In this respect it much closer resembles otoliths of the Solea Group. Anyhow, more material has to be awaited for further discussions of this matter. Apionichthys KAUP 1858 Type-species: Apionichthys dumerili KAUP 1858 syn. Soleotalpa GÜNTHER 1862 (type-species: Soleotalpa unicolor, syn. A. dumerili) Diagnosis: Moderately thickset roundish otoliths; ventral rim moderately deep, gently curving, with rounded postventral angle, dorsal rim more shallow, with broadly rounded pre- and postdorsal angles and a wide middorsal notch, anterior rim broadly rounded, posterior rim nearly vertically cut with median notch. Index l:h 1.15. Otolith size small, probably not exceeding much 2 mm. Sulcus shallow, rather narrow, centrally positioned, with rounded terminations anteriorly 280 Achiropsis STEINDACHNER 1876 Type-species: Achiropsis nattereri STEINDACHNER 1876 a b c Fig. 707: Apionichthys dumerili KAUP 1858 – 15 × close to the anterior rim of the otolith. Ostium not or just slightly wider than cauda, but much longer. Dorsal and ventral depressions narrow, rather shallow, but well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims rather thickset. Measurements: dumerili l:h 1.15 h:t 2.1 ol:cl 2.7 oh:ch 1.15 con.i 2.5 Side dimorphism: No data. Ontogeny: The only investigated otolith of this genus is less than 1.5 mm long and probably does not represent a fully adult specimen. Nevertheless, its appearance is quite characteristic and I therefore assume that in this case even very small otoliths may be diagnostically mature. Remarks: A specimen of A. nattereri in the ZMUC collection was x-rayed and revealed that otoliths have been dissolved (by formalin). Species and distribution: Two species from the Atlantic coast of South America – A. nattereri and A. normani. Soleonasus EIGENMANN 1912 Type-species: Soleonasus finis EIGENMANN 1912 Remarks: Soleonasus is a monospecific genus – S. finis. Otoliths of this rare species from the coasts and rivers of British Guiana have not been available for investigation. Pnictes JORDAN 1918 Type-species: Achiropsis asphyxiatus JORDAN & GOSS 1886 Remarks: Pnictes is a monospecific genus – P. asphyxiatus. Otoliths of this rare species from the coast of Brazil and the Amazonas river system have not been available for investigation. Discussion: See entry to group. Soleinae Species and distribution: A single species – A. dumerili – from the coast of the Guianas, South America. 7.8.3 Solea Group Apionichthys dumerili KAUP 1858 Fig. 707 Genera: Microchirus, Monochirus, Dicologlossa, Quenselia, Solea, Dageichthys, Microbuglossus, Bathysolea, Vanstraelenia. This group is also well known from the fossil record of Europe since Oligocene times. syn. syn. syn. syn. Soleotalpa unicolor GÜNTHER 1862 Apionichthys ottonis STEINDACHNER 1868 Apionichthys nebulosus PETERS 1869 Apionichthys bleekeri HARST 1879 Investigated otoliths: 1 otolith (left side) from British Guiana, BMNH 1984.8.8.336-337. Distribution: South America, coasts of the Guianas. Definition and relationship: The genera incorporated in this group represent the core of the Soleinae that probably has given rise to the more advanced groups of the subfamily discussed later. Their otoliths come closest to what could be described as the typical Soleid pattern. They are roundish, compressed, with a deep ventral and a shallow dorsal margin. Except for Bathysolea and Vanstraelenia the inner face is distinctly convex, the outer face flat or slightly convex. The sulcus Schwarzhans: Pleuronectiformes 281 generally is rather shallow (although the cauda may be somewhat deepened) anteriorly reaches close to the rim and is indistinctly separated into an ostium and a cauda, the latter being somewhat shorter. The circumsulcal depression is well developed and well connected around the cauda. As already stated a number of more specialized groups may have originated from near the Solea Group. First to mention is the Synaptura Group with its characteristic elongated otoliths and the tendency to develop a bipartite ostium. Also the Brachirus Group is closely related and its limits to the Solea Group in fact are somewhat fluent. Typical members of the Brachirus Group are characterized by their distinctive otolith outline which in fact resembles the Achirinae (see respective entry). Finally, the Zebrias Group may have developed from the Brachirus Group. Its members are characterized by the tendency to fused colliculi and a deepened sulcus. The Solea Group thus is regarded as the most plesiomorphic unit of the Soleinae. Measurements: variegatus luteus boscanion †frequens †kirchbergeanus †latior †wienrichi (ad.) †wienrichi (juv.) l:h 1.05-1.20 1.20-1.25 1.15-1.20 1.05-1.15 1.20-1.35 1.00-1.15 1.25-1.35 1.10-1.20 h:t 2.8-3.5 2.3 3.0 2.5-2.7 2.5-3.0 2.5 2.3-2.5 2.7-3.5 ol:cl 1.2-1.4 1.4-2.0 1.1-1.2 1.1-1.4 1.1-1.3 1.2-1.3 1.1-1.3 1.1-1.5 oh:ch 1.0 1.0-1.1 1.0 0.8-1.0 1.0 1.0 0.9-1.0 0.9-1.2 con.i 2.8-3.3 3.2-3.5 3.0-3.5 2.0 2.8-3.3 2.5 4.0-4.3 2.8-3.5 Side dimorphism: Side dimorphism is very feeble in the species of this genus or else submerges in the considerable variability. Sometimes otoliths of the right side show less separated colliculi and some radial furrows within the circumsulcal depression. syn. Buglossus GÜNTHER 1862 (type-species: Pleuronectes variegatus) syn. Buglossidium CHABANAUD 1930 (type-species: Solea lutea) syn. Microchiropsis CHABANAUD 1956 (typespecies: Solea boscanion) Ontogeny and variability: Usually, specimens below a size of 1.5 to 2 mm do not exhibit all pertinent diagnostically valid features. They are so generalized in appearance that they can hardly be separated on species level. An exception from this is the fossil species M. wienrichi which shows some special morphological development in juveniles (see respective entry). Variability in this genus is rather strong and mostly concerns the outline of the otoliths and the proportions of sulcus and otolith. Since the overall morphological pattern is rather simple, it can become difficult at times even with adult specimens to distinguish between related species. In fossils this means that at times phenotypical species could in fact represent species groups and they should be dealt with accordingly and carefully. Diagnosis: Moderately thickset to thickset compressed otoliths; ventral rim deeply and regularly curving, dorsal rim more shallow, with broadly rounded postdorsal angle, anterior rim broadly rounded, posterior rim blunt, nearly vertically cut or broadly rounded. Index l:h 1.00 to 1.35. Otolith size up to 4 mm, diagnostic maturity reached at about 1.5 to 2.0 mm. Sulcus rather shallow and narrow, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium not wider than cauda, sometimes more narrow, and not much longer. Dorsal and ventral depressions rather wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims mostly thickset. Discussion: Closely related genera are Monochirus, Dicologlossa and Quenselia. The latter has usually been placed in synonymy with Microchirus in recent literature. The typical thin appearance of the otoliths, however, have led me to regard Quenselia as a separate genus, morphologically intermediate between Microchirus and Dicologlossa. Probably even more closely related or synonymous is Monochirus. Also, the two specialized genera Bathysolea and Vanstraelenia may have originated from near Microchirus. They are both characterized by the flat inner face and the massive convex outer face. There has been some confusion about the nature of the genus Buglossidium in literature and the delimitation of its species as to those of Microchirus. M. boscanion has been regarded at times as synonym of Buglossidium luteum (TORCHIO Microchirus BONAPARTE 1833 Type-species: Pleuronectes microchirus DELAROCHE 1809 (syn. M. variegatus) Piscium Catalogus, Part Otolithi piscium, Vol. 2 282 708a 709a 708c 708b 710a 709b 710b 711a 711b 712 711c Figs. 708-712: Microchirus variegatus (DONOVAN 1808) – 10 × 1973), suspected as hybrid of Buglossidium luteum and M. variegatus (CHABANAUD 1939, but ruled out by observations of NIELSEN, 1963), or been placed in Microchirus (DESOUTTER 1994). Having studied otolith of the three species in question, I must in deed agree that they are very similar to each other, in particular so M. luteus and M. boscanion. The conclusion I have drawn is such that there does not seem to be much good reason to keep both genera separate. Based on otolith analysis I therefore suggest to regard Buglossidium as a junior synonymy of Microchirus. Recently, the genus Microchirus and related genera have been revised by DESOUTTER (1994). In her review Microchirus is split into two subgenera – Microchirus and Zevaia. The latter corresponds to the genus Quenselia as presented here, only that its type-species – Q. ocellata – is excluded by DESOUTTER and left in her subgenus Microchirus. On the other hand she does include M. (Z.) hexophthalma which is placed here in the related genus Dicologlossa (although placement in the genus Quenselia would be a viable alternative according to otoliths; see respective entries). Buglossidium was regarded by DESOUTTER as a valid monospecific genus. Species and distribution: Regarding Buglossidium as synonymy of Microchirus there are at least three recent species to be placed in this genus – M. variegatus, M luteus and M. boscanion – all from the shores of Europe and North Africa. The generic status of two further North African species usually placed in Microchirus – M. wittei and M. frechkopi – remains uncertain at the time. DESOUTTER (1994) has them in her subgenus Microchirus (see above). They could also be representatives of the genus Quenselia. In addition there Schwarzhans: Pleuronectiformes 283 are four fossil species representing the genus from the Oligocene and Miocene of Europe – M. frequens, M. kirchbergeanus, M. latior and M. wienrichi. species from the Pliocene of France and the Middle Miocene of Poland are probably erroneous (see chapter 4.2). Microchirus variegatus (DONOVAN 1808) Figs. 708-712 Microchirus luteus (RISSO 1810) Figs. 716-717 syn. syn. syn. syn. Pleuronectes microchirus DELAROCHE 1809 Pleuronectes mangili RISSO 1810 Pleuronectes fasciatus NARDO 1827 Monochirus lingula COSTA 1847 Investigated otoliths: 3 otoliths from recent specimens (2 left side and 1 right side) from Plymouth, England, 2 otoliths (figs. 708-709) ZMH Ot.7.5. 1995.1-2 (leg. BMNH 1988.10.11.278-292), 1 otolith (fig. 710) BMNH 1988.10.11.278-292; 2 fossil otoliths (figs. 711-712) from the Lower Pliocene of Belgium, harbor of Antwerp, coll. Schwarzhans. Variability: Morphological variations within this species like in most species of the genus are quite considerable concerning outline of the otolith as well as certain proportions of the otolith and the sulcus. At the same time the otolith pattern is very simplified, and therefore distinction from related species may not always be possible (see below). syn. Monochirus minutus PARNELL 1837 Investigated otoliths: 2 otoliths (left side) from Plymouth, England, ZMH Ot.7.5.1995.3 (leg. BMNH 1988.10.11.176-8) and BMNH 1988.10.11. 176-8 Variability: The two specimens figured and those depicted in various previous publications indicate that the morphological variability found in this species is even bigger than in M. variegatus, especially as far as the outline of the otoliths are concerned. From this it seems doubtful that otoliths of M. luteus could always be differentiated from those of the two related species M. variegatus and M. boscanion. In fact, the fishes themselves also seem to be difficult to be distinguished and in the past obviously have been confused to a certain extent. Discussion: See entry to M. variegatus. Discussion: Otoliths of M. variegatus are very similar to those of the two other recent species investigated – M. boscanion and M. luteus – in most aspects. Those of M. luteus usually are a bit more thickset with a higher ol:cl index and those of M. boscanion show a lower ol:cl index. Of the fossil species M. frequens and M. latior resemble closest. Both are more gently rounded in outline and show a more strongly convex inner face. Also the predorsal portion is usually more pronounced than is the case with M. variegatus. M. frequens differs further in the unusually low index oh:ch (less than 1.0) indicating that the cauda is wider than the ostium. However, differentiation of all these species by otoliths alone may not always be possible. Distribution: Recent in the Mediterranean and the Northeast-Atlantic from Senegal to North of the British Isles at depth between 80 and 400 m. Also known as fossil from the Pliocene and Pleistocene of Belgium. Other fossil records of this Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Mediterranean to western Black Sea and Northeast-Atlantic from Scotland to southern Morocco. Microchirus boscanion (CHABANAUD 1926) Figs. 713-715 syn. Microchirus australis CHABANAUD 1950 Investigated otoliths: 3 otoliths (2 left side, 1 right side) from West Africa, 14°W/8°N, ZMH Ot.7.5.1995.4-5 (leg. BMNH 1956.7.12.16-19) and BMNH 1956.7.12.16-19. Variability: Unlike the other two recent species described above, the variability in M. boscanion seems to be rather limited. Discussion: See entry to M. variegatus. – M. boscanion at various times has been regarded as a 284 714a 713a 714b 713b 713c 715 716a 716c 717a 717b 716b Figs. 713-715: Microchirus boscanion (CHABANAUD 1926) – 15 × Figs. 716-717: Microchirus luteus (RISSO 1810) – 15 × synonym of M. luteus or as a hybrid of M. luteus and M. variegatus. Both assumptions are not substantiated by otolith analysis. Distribution: West African coast from the Straight of Gibraltar to Angola, in the North overlapping with both M. variegatus and M luteus. Schwarzhans: Pleuronectiformes 285 718a 720 718c 719 718b 722 721a 721c 723 724 721b Figs. 718-724: Microchirus frequens (STEURBAUT 1984) – 15 × Microchirus frequens (STEURBAUT 1984) Figs. 718-724 [?syn.Solea approximata KOKEN 1891 – KOKEN 1891: pl. 5, fig. 13 – holotype lost, figure and description of holotype inconclusive, species rejected] syn. Solea approximata – WEILER 1942: pl. 4, figs. 44-46 ?syn. Solea approximata – WEILER 1942: pl. 4, figs. 47-49, 51, non fig. 50 ?syn. Solea approximata – HEINRICH 1969: pl. 13, figs. 1,3,5 syn. Solea approximata – SCHWARZHANS 1974: fig. 57, pl. 3, fig. 15 syn. Microchirus sp. – NOLF & STEURBAUT 1979: pl. 5, figs. 27-29 syn. Solea approximata – MENZEL 1980: pl. Piscium Catalogus, Part Otolithi piscium, Vol. 2 2, fig. 6 syn. Solea approximata – MENZEL 1982: pl. 2, fig. 5 ?syn. Buglossidium aff. approximatum – GAEMERS & SCHWARZHANS 1982: pl. 2, figs. 12, 24-26, pl. 10, fig. 5 ?syn. Soleidarum sp. – GAEMERS & SCHWARZHANS 1982: pl. 10, fig. 4 syn. Solea approximata – MENZEL 1983: pl. 4, fig. 6 syn. Buglossidium frequens STEURBAUT 1984 – STEURBAUT 1984: pl. 35, figs. 9-18 syn. Buglossidium approximatum – MÜLLER 1990: pl. 5, fig. 8 syn. Buglossidium approximatum – MÜLLER 1994: pl. 10, figs. 6, 7, 12, 14, 17 syn. Solea approximata – SCHWARZHANS 1994: figs. 525-528 286 Remarks: Practically all publications dealing with fossil otoliths from the Oligocene and Miocene of the North Sea Basin have cited only one soleid species – Solea approximata KOKEN 1891. After having reviewed the type specimens of Buglossidium frequens STEURBAUT 1984 from the Lower Miocene of France it has become obvious that this nominal species is identical with those otoliths described as S. approximata from the Upper Oligocene of the North Sea Basin. It is not yet certain whether or not this species also extends into the Lower Miocene of the North Sea Basin. Those otoliths I have investigated from the Miocene of the North Sea Basin all represent a different species described in the following as M. wienrichi. KOKEN (1891) based Solea approximata on a single and small specimen from the Middle Miocene of Northern Germany. The holotype must now be regarded as lost. His drawing is so generalized that it is impossible to judge the nature of the species from it. It is to remind that a bothid – Arnoglossus holleri – occurs parallelly and his drawing is such that it could even represent this species. Despite the apparent priority of KOKEN’s description and the wide usage of Solea approximata in past literature I therefore propose to reject this species in favor of M. frequens and M. wienrichi respectively. Investigated otoliths: Numerous specimens from the Upper Oligocene of northern Germany; figured specimens are from Kassel (fig. 722, coll. Schwarzhans), Meerbusch-Osterath near Düsseldorf (fig. 721, coll. Neumann) and Krefeld Kempener Feld (figs. 723-724, coll. Neumann and coll. Schwarzhans). In addition the type material of Buglossidium frequens from the Lower Miocene (Burdigalian) of Paillou (Aqutaine Basin, France) was reviewed; figured specimens are the holotype (IRSNB-P 4251, fig. 718) and two paratypes (IRSNB-P 4252-53, fig. 719; IRSNB-P 4254-59, fig. 720). Ontogeny and variability: Otoliths of less than 2.0 mm (figs. 723-724) are somewhat generalized in morphology and may not exhibit all pertinent diagnostic features. In particular the widening of the cauda, characteristic for this species, may not be completed. Like in most species of the genus Microchirus variability is considerable and concerns detail of the outline as well as certain proportions of the sulcus. Discussion: M. frequens differs from the recent M. variegatus in the more gently rounded outline, the pronounced predorsal portion, the more strongly convex inner face and the rather wide cauda. M. kirchbergeanus from the Miocene of the Paratethys is more elongated and M. latior, also from the Miocene of the Paratethys lacks the widened cauda and at least in adults is more compressed. M. wienrichi, finally, from the Miocene of the North Sea Basin is characterized by its peculiar outline of the otolith, the rather short sulcus and (in adults) the rather flat inner face. Distribution: Upper Oligocene and Lower Miocene of France (Aquitaine Basin), Upper Oligocene (?to Middle Miocene) of northern Germany, Belgium and the Netherlands. Most if not all records from the Miocene of the North Sea Basin represent the species M. wienrichi described as new in the following. It is assumed that M. frequens represents an indigenous species of the North Sea Basin during Upper Oligocene and with the beginning of Miocene invaded the Northeast Atlantic through the then opening connection north of the British Isles. Microchirus kirchbergeanus (H.v.MEYER 1852) Figs. 725-729 syn. Solea kirchbergeana H.v.MEYER 1852 – H.v.MEYER 1852: pl. 17, figs. 2-3 syn. Solea antiqua H.v.MEYER 1852 – H.v.MEYER 1852: pl.17, figs. 4-7 (according to WEILER 1955) syn. Solea subvulgaris SCHUBERT 1906 – SCHUBERT 1906: pl. 5, fig. 53,55 syn. Solea kirchbergeana – WEILER 1955: figs. 9-10 (otoliths found in situ) syn. Solea approximata – JONET 1973: pl. 4, figs. 140-141 ?syn. Solea approximata – JONET 1979: pl. 2, fig. 17 syn. Solea kirchbergeana – REICHENBACHER 1988: pl. 1, figs. 5-6 ?syn. Dicologlossa sp. – BRZOBOHATY 1989: pl. 2, fig. 7 syn. Dicologlossa aff. cuneata – RADWANSKA 1992: pl. 38, fig. 8 syn. Buglossidium sp. – BRZOBOHATY 1994: pl. 1, fig. 11 Schwarzhans: Pleuronectiformes 287 726a 727a 726b 725a 726c 727b 725b 728 729 Figs. 725-729: Microchirus kirchbergeanus (H.v.MEYER 1852) – 15 × Remarks: M. kirchbergeanus is the only fossil Pleuronectiform from which otoliths have been described in situ (WEILER, 1955). Synonymization with Solea subvulgaris described by SCHUBERT (1906) is mainly based on WEILER’s excellent drawing of the otolith found in situ although it shows a somewhat atypical undulating outline. Apparently, WEILER’s specimen was rather small. Recently, this interpretation has been confirmed by two isolated otolith findings of this species at the type-locality described by REICHENBACHER (1988). Investigated otoliths: 6 otoliths, the lectotype (GBW 1906/1/47a, fig. 727) and 2 paralectotypes (GBW 1906/1/47c, fig. 726 and GBW 1906/1/47b) of Solea subvulgaris from the Middle Miocene (Badenian) of Bad Vöslau, Austria, 1 otolith (fig. 725) from the Middle Miocene (Badenian) of Poland (ZPalUW RaK-454, described by RADWANSKA, 1992 as Dicologlossa aff. cuneata) and 2 otoliths (figs. 728-729) from the Lower Miocene (Burdigalian) from Costa da Caparica, Portugal (coll. Schwarzhans) Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Otoliths of M. kirchbergeanus are more elongate than those of other recent or fossil species of the genus except for M. wienrichi which, however, differs in a number of other specialized features (see respective entry). Other than that otoliths of M. kirchbergeanus are very generalized in appearance and not very characteristic. M. kirchbergeanus is regarded here in rather wide limits and it may not in fact represent a single species but possibly a group of two or more related species that cannot be distinguished by means of otoliths. This conspicuousness is build on the very simplified morphology that it exhibits, the high variability and the wide distribution pattern. May be once, when large amounts of data (from adult specimens) from the various locations and time intervals have been gathered it could become possible to distinguish more than one species. Until such fictional date one should be aware that M. kirchbergeanus represents a phenotypic species or species group. Distribution: Known from otoliths and skeletons with otoliths “in situ” from the Middle Miocene of Bavaria, otoliths alone from Austria, Poland and the Lower Miocene of Portugal 288 731a 732 730 731c 731b 733 Figs. 730-733: Microchirus latior (SCHUBERT 1906) – 15 × Microchirus latior (SCHUBERT 1906) Figs. 730-733 Microchirus wienrichi n.sp. Figs. 734-741 syn. Solea latior SCHUBERT 1906 – SCHUBERT 1906: pl. 6, figs. 12-14 ?syn. Solea latior – ANFOSSI & MOSNA 1979: pl. 4, fig. 14 syn. Microchirus aff. variegatus – BRZOBOHATY 1989: pl. 2, fig. 8 syn. Buglossidium frequens – BRZOBOHATY 1989: pl. 2, fig. 9 syn. Microchirus aff. variegatus – RADWANSKA 1992: pl. 38, fig. 9 ?syn. Solea approximata – WEILER 1958: pl. 3, fig. 17-19 syn. Solea approximata – GAEMERS 1971: pl. 3, fig. 16, pl. 9, fig. 5 syn. Solea approximata – NOLF 1976: pl. 17, figs. 21-23 syn. Buglossidium approximatum – HUYGHEBAERT & NOLF 1979: pl. 6, figs. 22, 23, ?24 syn. Soleidarum sp. 2 – GAEMERS & SCHWARZHANS 1982: pl. 2, fig. 24 Investigated otoliths: 5 otoliths, the lectotype (GBW 1906/1/58b, fig. 731) and 2 paralectotypes (GBW 1906/1/58a, fig. 732, GBW 1906/1/58c) from the Middle Miocene (Badenian) of Bad Vöslau, Austria, 1 otolith (fig. 733) from the Middle Miocene (Badenian) of Poland (ZPalUW RaNi448, described as Microchirus aff. variegatus by RADWANSKA, 1992), 1 otolith (fig. 730) from the Lower Miocene (Eggenburgian) of Mold, Austria (coll. Schwarzhans). Name: In honor of Günther Wienrich (Weetze, NW-Germany), who has collected most of the type-material. Holotype: Fig. 737, SMF P 9321. Type locality: Water well Lüllingen near Kevelaer, NW-Germany. Age: Reinbekian, lower Middle Miocene. Paratypes: 9 otoliths, 7 topo- and stratitypic (figs. 736, 738-741, SMF P 9322), 1 Reinbekian of Dingden near Bocholt (fig. 734, SMF P 9323) and 1 Hemmoorian (fig. 735), Lower Miocene from Miste near Winterswijk (Netherlands) (SMF P 9324). Discussion: Very close to M. variegatus, but differing in the more regularly and gently curving outline and the more convex inner face. M. latior shows the most compressed otoliths of all Microchirus species, at least in adults. Distribution: Lower and Middle Miocene of Austria, Czechoslovakia and Poland. Diagnosis: Compressed, moderately small otoliths with almost circular outline. Predorsal projection angular, but not very strong, postdorsal projection strong, postventral angle shifted far backwards, posterior rim undulating in juveniles. Schwarzhans: Pleuronectiformes 289 734c 735a 734a 734b 735b 738a 737a 736a 736b 739 738a 737a 736b 740b 740a 741 Figs. 734-741: Microchirus wienrichi n.sp. – 15 × Sulcus rather short, terminating at considerable distance from the posterior rim of the otolith. Otoliths thin and inner face convex in juveniles, more thickset and with flattened inner face in adults. Description: Outline: Otoliths small (not exceeding 3 mm) with compressed, roundish outline. Dorsal rim often with angular but not very strong predorsal projection and massive rounded postdorsal projection, postventral portion sometimes angular, shifted far backwards; anterior and posterior tips blunt, the latter often undulating. Otoliths moderately thickset. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Inner Face: Convex in juveniles, rather flat in adults, smooth. Sulcus rather short, terminating at considerable distance from the posterior tip of the otolith, rather narrow and moderately deep. Ostium not much longer than cauda and usually not wider, too. Colliculi indistinctly separated and somewhat deepened. Circumsulcal depression well developed and rather wide. Other views: Rims smooth, sharp in juveniles, thickset in adults. Outer face smooth, almost flat in juveniles, convex in adults. Side dimorphism: Not apparent. 290 Ontogeny and variability: M. wienrichi is a species with a rather unusual high degree of ontogenetic changes. Smaller otoliths to approximately 1.7 mm (figs. 738-741) are more compressed, show a more undulating outline, are rather thin with a convex inner face and a nearly flat outer face and exhibit a more narrow sulcus. Larger otoliths above 2.0 mm (figs. 734-736) are slightly more elongate, much more thickset with a flattened inner face and a convex outer face and show a wider sulcus and a smoothed outline. In fact this is one of the rare instances where juvenile otoliths can be identified easier than adults. Variability in this species is moderate, mostly concerning details of the outline and the width of the sulcus. Anyhow, specimens of M. wienrichi remain more characteristic than those of most other species of Microchirus. Discussion: The diagnostic pattern of M. wienrichi distinguishes it well from other otoliths of the genus including M. frequens from the Upper Oligocene of the area. Remarks: The reason for rejection of the species Solea approximata, which otherwise could be in conflict with M. wienrichi, is given in the description of M. frequens. Measurements: hispidus l:h h:t 1.30-1.35 2.8-3.0 ol:cl 1.6 oh:ch 1.0 con.i 2.8-3.0 Side dimorphism: Otoliths of the right (eyed) side show a narrower sulcus, a complete lack of the separation of the colliculi and some radial furrows in the zone near to the circumsulcal depression. Discussion: Monochirus apparently is closely related to Microchirus and in fact judging from the otoliths the latter could even be placed included as a synonymy. Main differences are the more elongate shape of the otolith and the poorly defined separation of the colliculi. Species and distribution: Monochirus is a monospecific genus with M. hispidus distributed throughout the Mediterranean and in the Northeast-Atlantic from Portugal to Ghana. Monochirus hispidus RAFINESQUE 1814 Figs. 742-744 syn. Pleuronectes trichodactylus NARDO 1827 syn. Monochirus atlanticus CHABANAUD 1949 Distribution: Lower and Middle Miocene of northern Germany, Belgium and the Netherlands. Investigated otoliths: 3 otoliths (2 left side, 1 right side) without location, IRSNB (coll. Nolf, leg. Chaine). Monochirus RAFINESQUE 1814 Type-species: Monochirus hispidus RAFINESQUE 1814 Distribution: Mediterranean and NE-Atlantic from Portugal to Ghana at depth down to 250 m. Diagnosis: Moderately thin, rather elongate otoliths; ventral rim moderately deep and regularly curving, dorsal rim more shallow, with somewhat anteriorly projecting predorsal angle, anterior rim inclined, posterior rim rounded. Index l:h 1.30 to 1.35. Otolith size small, not exceeding 3 mm. Sulcus not much deepened and rather narrow, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium not wider than cauda, but much longer. Colliculi poorly defined and poorly separated. Dorsal and ventral depressions rather wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims rather sharp. Quenselia JORDAN 1889 Type-species: Pleuronectes ocellatus LINNAEUS 1758 syn. Echinosolea CHABANAUD 1927 (type-species: Pleuronectes ocellatus) syn. Zevaia CHABANAUD 1943 (type-species: Solea azevia) Diagnosis: Thin otoliths with very regular roundish outline; ventral rim deeply and very regularly curving, dorsal rim also regularly rounded, but sometimes with pre- and/or postdorsal angles, anterior and posterior rims broadly rounded. Index l:h 1.15 to 1.25. Otolith size up to 5 mm, diagnostic maturity reached relatively early at Schwarzhans: Pleuronectiformes 291 742a 742c 742d 742b 743 744b 744a Figs. 742-744: Monochirus hispidus RAFINESQUE 1814 – 15 × about 1.5 mm. Sulcus shallow, narrow and rather long, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium not wider than cauda, sometimes more narrow, but much longer (except for the fossil Q. cornuta, the only Soleid in which the cauda is longer than the ostium). Dorsal and ventral depressions narrow, not very deep and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth or delicately ornamented towards the rims; outer face flat to slightly concave, smooth. Rims sharp. Measurements: ocellata azevia †cornuta l:h h:t 1.25 3.7-4.0 1.25 4.2-4.6 1.05-1.15 3.0-3.2 ol:cl 1.2-1.5 1.3-1.5 0.5-0.7 oh:ch 0.9-1.0 0.9 1.0 con.i 3.0 3.0-3.5 2.5-2.7 Side dimorphism: Side dimorphism is very feeble in the species of this genus or else submerges in the variability. Ontogeny and variability: Smaller otoliths are only known from the somewhat peculiar fossil species. However, even small specimens below 1.5 mm are quite characteristic and unmistakable. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Also the level of variability in this genus is rather restricted, mainly concerning details of the outline of the otolith and the ornamentation on the inner face. Discussion: In recent ichthyological literature Quenselia is usually understood as a junior synonym of Microchirus. The otolith pattern, however, has let me to regard Quenselia as a valid genus and separate it from Microchirus. Quenselia otoliths are characterized by their very thin appearance and the very regular ovale outline. Morphologically, they are intermediate between those of Microchirus and the related genus Dicologlossa, probably representing a lineage of specialization. Dicologlossa otoliths are more elongate and show a tendency to enlarge their caudal colliculum. (This is a similar trend as is observed in the peculiar fossil Q. cornuta.) Dicologlossa hexophthalma represents an almost perfect link between the two genera (see respective entry). In a recent review of the genus Microchirus DESOUTTER (1994) regarded Quenselia as a synonym, discriminating two subgenera – Microchirus and Zevaia (for more details see entry to Microchirus). Otolith analysis does not support DESOUTTER’s view of the type-species – Q. ocellata – to represent a member of the genus Microchirus. 292 745a 746a 745c 746b 745b 747 748 750a 749a 749c 750b 749b Figs. 745-748: Quenselia ocellata (LINNAEUS 1758) – 10 × Figs. 749-750: Quenselia theophila (RISSO 1810) – 10 × Species and distribution: There are at least two recent species in the genus Quenselia – Q. ocellata and Q. theophila – known from the Mediterranean and the Northeast Atlantic. The generic status of two further African species usually placed in Microchirus – M. wittei and M. frechkopi – remains uncertain at the time (see also entry to Microchi- rus). Although placed into Microchirus by DESOUTTER (1994), they have also been regarded as representatives the genus Quenselia by CHABANAUD (1955). In addition, there is one fossil species placed in this genus – Q. cornuta – from the Lower Pliocene of NW-Morocco. Schwarzhans: Pleuronectiformes 293 753a 752a 751a 752c 753b 752b 751b 757 756 755 754 758b 758a Figs. 751-758: Quenselia cornuta n.sp. – 15 × Quenselia ocellata (LINNAEUS 1758) Figs. 745-748 Investigated otoliths: 2 otoliths (left and right side) from Portugal, ZMH Ot.9.5.1995.5 (leg. BMNH 1867.7.23.8) and BMNH 1867.7.23.8. syn. Solea quadriocellata von BONDE 1922 Investigated otoliths: 4 otoliths (2 left side and 2 right side) from Teneriffa, Canary Islands, ZMH Ot.9.5.1995.1-4 (coll. Schwarzhans). Discussion: Very similar to Q. azevia, but may be less thin and less ornamented on the inner face. Distinction of the two species by otoliths alone, however, will be very difficult. Distribution: Mediterranean and Northeast-Atlantic from Spain to Mauritania and including Madeira and the Canary Islands from shallow depth to 300 m. Quenselia theophila (RISSO 1810) Figs. 749-750 syn. Quenselia azevia (CAPELLO 1867) Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Very similar to Q. ocellata but even more thin and with intense delicate ornamentation on the inner face. Distribution: Western Mediterranean and Northeast-Atlantic from Portugal to Senegal. Quenselia cornuta n.sp. Figs. 751-758 Name: cornutus (lat.) = horn bearing, referring to the hornlike predorsal projection. Holotype: Fig. 752, SMF P 9325. Type locality: River banks of the Oued Beth due South of Dar Bel Hamri, northern Morocco. Age: Zanclian, Lower Pliocene. Paratypes: 6 otoliths (figs. 751, 753-757), topoand stratitypic, SMF P 9326. 294 Diagnosis: Small roundish otoliths with convex inner face. Predorsal projection hornlike. Caudal colliculum about twice as long as ostial colliculum. Description: Outline: Otoliths small (less than 2.5 mm), with compressed, irregularly roundish outline. Dorsal rim with prominent predorsal hornlike projection, postdorsally broadly rounded; ventral rim deeply curving; anterior and posterior rims broadly rounded, the posterior one more blunt so. Otoliths rather thin. Inner face: Rather strongly convex and smooth. Sulcus rather short and narrow, with slightly supramedian position and not much deepened. This is the only Soleid species in which the caudal colliculum is considerably longer than the ostial colliculum (about two times). The separation of the colliculi is rather distinct. Circumsulcal depression narrow, shallow, but well connected around the caudal tip of the sulcus. Other views: Outer face smooth, almost flat. Rims sharp. Side dimorphism: In otoliths of the right side the hornlike predorsal projection seems to be generally less well developed. Ontogeny and variability: Specimens are present down to about 1 mm in size but do not show any major ontogenetic changes. Variability likewise is rather moderate, restricted mainly to details of the outline and proportions of the sulcus. Discussion: This species is immediately recognized by its unusually long cauda which is about two times as long as the ostium, a unique character amongst otoliths of the Soleidae. This and the compressed outline with the hornlike predorsal projection result in a very typical morphology which only tentatively is placed in the genus Quenselia. A single finding of a similar otolith from the Upper Miocene (Tortonian) of Cacela in southern Portugal (fig. 758, coll. Schwarzhans) differs in the lack of the extended cauda. It is referred to as Q. aff. cornuta. If this otolith represents the predecessor of Q. cornuta, as it seems likely, this would be an indication that the peculiar expansion of cauda and caudal colliculum is a derived feature not to be mistaken with the plesiomorphic long cauda found in members of the Psettodidae and the Tephrinectes, Paralichthodes and Ammotretis Groups. Dicologlossa CHABANAUD 1927 Type-species: Solea cuneata MOREAU 1881 syn. Xenobuglossus CHABANAUD 1950 (typespecies: X. elongatus) Diagnosis: Thin and rather elongate otoliths; ventral rim shallow and regularly curving, dorsal rim also shallow, with broadly rounded preand postdorsal angles, anterior and posterior rims broadly rounded. Index l:h 1.20 to 1.70. Otolith size up to 5 mm, diagnostic maturity reached at about 1.5 mm. Sulcus rather shallow and narrow, position almost median, anteriorly reaching close to the anterior rim of the otolith. Ostium not wider than cauda, sometimes more narrow, and about equal in length. Dorsal and ventral depressions rather narrow, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face convex, smooth; outer face almost flat, smooth. Rims sharp. Measurements: hexophthalma cuneata (left) cuneata (right) †patens l:h h:t ol:cl 1.40-1.45 4.5 0.85-1.05 1.45-1.70 3.2-3.7 1.60-1.80 1.45-1.55 3.2-3.7 1.05-1.10 1.20-1.35 3.0 1.60-1.70 oh:ch 0.8-0.9 1.0 1.0 1.1 con.i 5.5 3.5-4.0 3.5-4.0 2.5-2.8 Side dimorphism: Only apparent in D. cuneata. There, otoliths of the right side have a much more expanded cauda, almost to the size of the ostium, whereas in otoliths of the left side the cauda is much shorter than the ostium. Ontogeny and variability: As in the related genus Quenselia ontogenetic changes seem to be rather small. Variability is quite changeable in the species of this genus. In D. hexophthalma it remains at a low level, in the fossil D. patens it is moderate, but in D. cuneata it is considerable. There, mostly features of the outline and proportions of the otoliths are concerned. Discussion: Dicologlossa is closely related to Quenselia and marks the final stage of lineage probably having originated from near Microchirus. Like the fossil Quenselia cornuta, otoliths of the genus Dicologlossa show a tendency to enlarge its cauda (but not as much – only to about the length of the ostium). Schwarzhans: Pleuronectiformes 295 759a 760 759c 759b 762 761 Figs. 759-762: Dicologlossa hexophthalma (BENNETT 1831) – 10 × Species and distribution: Two recent species – D. hexophthalma and D. cuneata – from the Mediterranean and the Northeast-Atlantic and one fossil species – D. patens – from the Miocene of Italy, Austria, France and Portugal. D. hexophthalma was regarded by DESOUTTER (1994) as a member of the genus Microchirus subgenus Zevaia (here as Quenselia; see also entry to Microchirus). Dicologlossa hexophthalma (BENNETT 1831) Figs. 759-762 Distribution: Northeastern Atlantic from Portugal to Angola including Madeira and the Canary Islands. Dicologlossa cuneata ( [DE LA PYLAIE 1835] MOREAU 1881) Figs. 763-766, 23 syn. syn. syn. syn. Solea angulosa KAUP 1858 Solea clerveleyi GILCHRIST 1906 Solea senegalensis mbaoensis PELLEGRIN 1907 Xenobuglossus elongatus CHABANAUD 1950 Investigated otoliths: 4 otoliths (2 left side and 2 right side), 2 from Lagos, Portugal and 2 from Teneriffa, Canary Islands, ZMH Ot.9.5.1995.6-9 (coll. Schwarzhans). Investigated otoliths: 8 otoliths (4 left and 4 right side), 4 from Portugal and 4 from La Rochelle, France, ZMH Ot.9.5.1995.10-17 (coll. Schwarzhans). Discussion: Otoliths of D. hexophthalma are less elongate than those of D. cuneata and also show always an extended cauda to about the size of the ostium. They also resemble otoliths of the genus Quenselia in habitus, differing mainly in being more elongate. Thus C. hexophthalma is morphologically intermediate between Quenselia and C. cuneata. Side dimorphism: Otoliths of the right side exhibit an enlarged cauda, whereas those of the left side do not. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Variability: Variability in this species is considerable and concerns the outline and the proportions of the otoliths. Occasionally, the posterior rim is expanded dorsally and pointed (fig. 766). 296 Discussion: See entry to D. hexophthalma. Distribution: Western Mediterranean and Northeast-Atlantic from the Bay of Biscay to the Cape of Good Hope. Dicologlossa patens (BASSOLI 1906) Figs. 767-769 syn. Solea patens BASSOLI 1906 – BASSOLI 1906: pl. 2, fig. 4 syn. Solea kokeni SCHUBERT 1906 – SCHUBERT 1906: pl. 20, fig. 8 syn. Solea kokeni – JONET 1973: pl. 4, fig. 144 syn. Pegusa sp. – NOLF & STEURBAUT 1979: pl. 5, fig. 30 syn. Solea kokeni – ANFOSSI & MOSNA 1979: pl. 4, fig. 15 syn. Solea aff. kokeni – JONET 1980: pl. 2, fig. 21 syn. Solea patens – STEURBAUT & JONET 1981: pl. 4, fig. 7 syn. Dicologlossa cuneata – STEURBAUT & JONET 1981: pl. 4, figs. 10-11 syn. Solea patens – STEURBAUT 1984: pl. 36, figs. 1-4 syn. Solea solea – RADWANSKA 1992: pl. 38, figs. 13-14 Investigated otoliths: 6 otoliths, the holotype of Solea kokeni (GBW 1906/1/55, fig. 768) from the Middle Miocene, Badenian of Bad Vöslau, Austria, 1 otolith from the Burdigalian, Lower Miocene of Costa da Caparica, Portugal (coll. Schwarzhans, fig. 769), 3 otoliths from the Badenian, Middle Miocene of Poland (ZPalUW RaK447,452,453; described by Radwanska as Solea solea; fig. 767). Discussion: Otoliths of D. patens are more compressed and more robust than those of the two recent species and also do not show an extended cauda. Quite clearly, they exhibit the most plesiomorphic otolith pattern in this genus. Distribution: Lower to Upper Miocene of Italy, Austria, France and Portugal Solea QUENSEL 1806 Type-species: Solea vulgaris QUENSEL 1806 syn. Pegusa GÜNTHER 1862 (type-species: Solea pegusa, syn. S. lascaris) syn. Synapturichthys CHABANAUD 1927 (typespecies: Synaptura sauvignyi, syn. S. kleini) syn. Barnardichthys CHABANAUD 1927 (typespecies: Solea fulvomarginata) Diagnosis: Moderately thickset to thickset, compressed to elongate otoliths; ventral rim moderately deep to deeply and regularly curving, dorsal rim more shallow, anteriorly broadly rounded, but posterior-dorsal portion usually extended and pointed, anterior rim broadly rounded, posterior rim blunt, often nearly vertically cut and with distinct concavity. Index l:h 1.10 to 1.50. Otolith size up to 4 mm, rarely up to 5.5 mm, diagnostic maturity reached at about 1.5 mm. Sulcus somewhat deepened and rather narrow, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium not or only slightly wider than cauda and much longer. Dorsal and ventral depressions moderately wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, not very smooth; outer face flat to slightly concave, smooth. Rims thin to moderately thickset. Measurements: senegalensis triophthalma aegyptiaca †rotunda vulgaris lascaris nasuta kleini l:h 1.40 1.45-1.50 1.25 1.15-1.25 1.20 1.10 1.15-1.20 1.10 h:t 3.0-3.3 3.5 3.3 2.0-2.5 3.0-3.2 3.1-3.3 3.0 3.6 ol:cl 1.7-2.1 1.9-2.2 1.8 1.5-2.3 1.4-1.7 1.8-1.9 2.3-2.4 1.7 oh:ch 1.0 1.1-1.2 1.1 1.0-1.2 1.1-1.2 1.1-1.3 1.1 1.0 con.i 3.3-3.7 3.0 3.3 1.7-2.2 2.3-2.5 2.4-2.5 2.3 3.0 Side dimorphism: Only occasionally apparent. In some species the otoliths of the right side show a more strongly convex inner face than those of the left side. Ontogeny and variability: Both ontogenetic changes and intraspecific variability in the species of this genus seem to be at rather moderate level. Schwarzhans: Pleuronectiformes 297 764 763a 763c 766 763b 765a 765b 768a 768c 767a 769 767b 768b Figs. 763-766: Dicologlossa cuneata (DE LA PYLAIE 1835) – 10 × Figs. 767-769: Dicologlossa patens (BASSOLI 1906) – 15 × Discussion: Most species of the genus Solea share the following features that readily distinguishes them from other genera of the group. This is the combine of a rather strongly convex inner face, the concave posterior rim and the rather high ol:cl index. Only few species, such as S. triophthalmus, S. aegyptiaca and possibly also S. bleekeri lack the concavity of the posterior rim. In most recent literature several of the species listed here under the genus Solea are being placed in a separate genus – Pegusa – based on the enlarged and specialized nostril on the blind side. However, otolith analysis does not seem to follow the same tracks. I have therefore chosen TORCHIO’s (1973) view and regard Pegusa as a junior synonym of Solea. Nevertheless, the otolith morphologies found in Solea can be differenPiscium Catalogus, Part Otolithi piscium, Vol. 2 tiated into three distinctive groups, which if verified by other ichthyological methods should be given generic or subgeneric ranking. The three groups are characterized as follows. Otoliths of S. senegalensis differ from all other members of the genus in the combination of being more elongate and showing a more flat inner face. They are also the ones growing to the largest size. There is quite some overall resemblance to otoliths of the genus Austroglossus the most plesiomorphic genus in the Synaptura Group and maybe this is from near where the Synaptura Group could have developed. The second group contains those species without the concavity at the posterior rim – S. triophthalma, S. aegyptiaca and probably also S. bleekeri (judging from a very eroded otolith investigated). 298 771a 770a 770c 771b 770b Figs. 770-771: Solea senegalensis KAUP 1858 – 10 × Finally, the third and largest group contains those species with a compressed outline, a strongly convex inner face and most notably a concave posterior rim. To this group belong all those species traditionally placed in the genus Pegusa such as S. lascaris, S. nasuta and S. kleini, but also the type-species of the genus Solea – S. vulgaris. In addition, the fossil S. rotunda belongs to this group as well. Species and distribution: There are at least 11 valid recent species in Solea distributed through the Mediterranean and the eastern Atlantic all the way from Europe to the tip of South Africa – S. aegyptiaca, S. bleekeri, (otoliths figured in SMALE et al. 1995), S. fulvomarginata, S. impar, S. kleini, S. lascaris, S. nasuta, S. senegalensis, S. stanalandi, S. vulgaris and S. triophthalma. Of all the fossil species formally recorded for Solea (more in the sense of a Soleidae) only one – S. rotunda – from the Miocene of France and Poland may remain in it. Discussion: Otoliths of S senegalensis are easily recognized by their elongate shape, the relatively flat inner face and the presence of a slight concavity at the posterior rim. Distribution: Northeast Atlantic from Portugal to Senegal at shallow depth down to 80 m. Solea triophthalma BLEEKER 1863 Figs. 772-773 Investigated otoliths: 2 otoliths (left and right side) from tropical West Africa, ZMH Ot.9.5.1995.20 (leg. BMNH 1953.6.22.2) and BMNH 1953.6.22.2. Discussion: Otoliths of S. triophthalma are recognized by the elongate shape, the lack of the posterior concavity and the very thin appearance with a convex inner and a concave outer face. Distribution: Tropical West Africa. Solea senegalensis KAUP 1858 Figs. 770-771 Solea aegyptiaca CHABANAUD 1927 Fig. 784 syn. Solea melanochira MOREAU 1874 Investigated otoliths: 2 otoliths (left and right side) from off Mauritania, ZMH Ot.9.5.1995.1819 (coll. Schwarzhans, leg. W. Schmidt). Investigated otoliths: 1 otolith (left side) from the Suez Channel, Egypt, BMNH 1925.9.19.142. Schwarzhans: Pleuronectiformes 299 773 772a 772c 772b 774a 775a 774c 774b 775b 776c 776a 777 776b Figs. 772-773: Solea triophthalmua BLEEKER 1863 – 10 × Figs. 774-777: Solea rotunda (PRIEM 1914) – 15 × Discussion: Similar to S. triophthalma but more compressed. Distribution: Mediterranean coast of North Africa and entering into the Suez Channel. Solea rotunda (PRIEM 1914) Figs. 774-777 syn. Gobius rotundus PRIEM 1914 – PRIEM 1914: fig. 66 syn. Solea rotunda – STEURBAUT 1984: pl.36, figs. 5-8 syn. Solea solea – RADWANSKA 1992: pl. 38, figs. 10-12 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 5 otoliths, 2 from the Burdigalian (Lower Miocene) of Pont Pourquey, Aquitaine Basin, France (IRSNB P 4272, 4273; figs. 774-775) and 3 from the Badenian, Middle Miocene of Poland (ZPalUW RaR-449, RaK-450, RaNi451; described by RADWANSKA, 1992 as Solea solea; figs. 776-777). Discussion: Also somewhat variable in expression otoliths of this species are best recognized by their near circular outline. The posterior rim, however, is still concave. Distribution: Lower Miocene of France (Aquitaine Basin), Middle Miocene of Poland. 300 779a 778a 778c 779b 778b 781 780a 780c 780b Figs. 778-779: Solea lascaris (RISSO 1810) – 10 × Figs. 780-781: Solea nasuta (PALLAS 1811) – 10 × Solea vulgaris QUENSEL 1806 Figs. 782-783 Investigated otoliths: 2 otoliths (left side) from Plymouth, England, ZMH Ot.9.5.1995.25 (leg. BMNH 1988.10.11.334) and BMNH 1988.10.11.334. ?syn. Pleuronectes solea LINNAEUS 1758 Investigated otoliths: 4 otoliths (2 left and 2 right side) from the German North Sea, ZMH Ot.9.5.1995.21-24 (coll. Schwarzhans). Discussion: Very similar to S. lascaris, but generally somewhat more elongate and with a wider sulcus. A large series of otoliths of this species was also figured by CHAINE (1936). Distribution: North Sea, western Baltic Sea, Northeast-Atlantic from Mid-Norway to Senegal, European coast of the Mediterranean and western Black Sea. Solea lascaris (RISSO 1810) Figs. 778-779 syn. Solea pegusa YARELL 1829 syn. Solea aurantiaca GÜNTHER 1862 syn. Solea margaritifera GÜNTHER 1862 Discussion: Otoliths of S. lascaris are somewhat more compressed than those of S. vulgaris due to the deeper ventral rim and less rounded in outline than those of S. nasuta. A large series of otoliths of this species was also figured by CHAINE (1936). Distribution: Mediterranean, southern North Sea and East-Atlantic from SW of Great Britain to South Africa at depth from 30 to 350 m. Solea nasuta (PALLAS 1811) Figs. 780-781 Investigated otoliths: 2 otoliths (left and right side) from the Black Sea off Rumania, ZMH Ot. 9.5.1995.26 (leg. BMNH 1964.12.7.3) and BMNH 1964.12.7.3. Discussion: Very similar to S. lascaris but more circular in outline. Probably very difficult to distinguish. Schwarzhans: Pleuronectiformes 301 783a 782c 782a 783b 782b 785a 784a 784c 784b 785b Figs. 782-783: Solea vulgaris QUENSEL 1806 – 10 × Fig. 784: Solea aegyptiaca CHABANAUD 1927 – 10 × Fig. 785: Solea kleini (RISSO 1810) – 10 × Distribution: Black Sea and Mediterranean. Solea kleini (RISSO 1810) Fig. 785 syn. Synaptura savignyi KAUP 1858 syn. Solea capellonis STEINDACHNER 1868 Investigated otoliths: 1 somewhat eroded otolith (left side) from Nice, southern France, BMNH 88.6.15.9. Discussion: Otoliths compressed, similar to S. lascaris and S. nasuta but always with somewhat crenulated rims and a less convex inner face. A large series of otoliths of this species was also figured by CHAINE (1936). Distribution: Mediterranean and all along the Atlantic coast of Africa to the tip of South Africa. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Dageichthys STAUCH & BLANC 1964 Type-species: Dageichthys lakdoensis STAUCH & BLANC 1964 Remarks: Dageichthys is an endemic monospecific freshwater genus exclusively recorded from the Benue river basin in Cameroon. No specimen of this rare species has been available for otolith extraction. Microbuglossus GÜNTHER 1862 Type-species: Solea humilis CANTOR 1850 (syn. M. ovatus) Diagnosis: Small, moderately thickset, compressed otoliths with a roundish outline; ventral and dorsal rims regularly curving, anterior and posterior rims broadly rounded. Index l:h 1.10 to 1.25. Otoliths small, its size not much exceeding 3 mm. 302 Sulcus somewhat deepened and moderately wide, position median to slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium usually not much wider than cauda and also not much longer. Dorsal and ventral depressions rather wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face slightly convex, moderately smooth; outer face almost flat, smooth. Rims moderately thickset. 2 (leg. BMNH 1984.1.12.83-86) and BMNH 1984.1.12.83-86. Discussion: Very similar to M. heini, but may be consistently somewhat more compressed. Distribution: Coasts of India to Malaysia and southern China. Microbuglossus heini (STEINDACHNER 1902) Figs. 789-791 Measurements: ovatus heini elongatus l:h 1.10-1.15 1.15-1.25 1.15-1.25 h:t 3.1 3.1 2.5 ol:cl oh:ch 1.55-1.75 1.0-1.2 nm about 1.0 1.4 1.0-1.3 con.i 3.0 3.0 3.0 Side dimorphism: Not apparent. Variability: Details of the outline, which anyway is not very characteristic, and certain proportions of the sulcus are apt to some variations. Discussion: The overall appearance of the otoliths of this ‘dwarfed’ genus is somewhat neotenic, resembling juvenile specimens of Solea and related genera. The main difference to otoliths of the genus Solea is the complete absence of any concavity at the posterior rim, but this character could be lacking in very small specimens of that genus as well. All in all, otoliths of Microbuglossus will be difficult to be distinguished from juvenile otoliths of other Soleidae if found isolated, particularly so as fossils. Because of the ‘neotenic’ appearance and the lack of a concavity at the posterior rim I have decided to keep Microbuglossus separate from Solea in contrast to most recent citations in ichthyological literature. Species and distribution: Three species from the Indian Ocean – M. ovatus, M. heini and M. elongatus. Microbuglossus ovatus (RICHARDSON 1846) Figs. 786-788 syn. Solea humilis CANTOR 1850 syn. Solea maculata BLEEKER 1851 Investigated otoliths: 3 otoliths (2 left side and 1 right side) from Singapore, ZMH Ot.14.5.1995.1- Investigated otoliths: 3 otoliths (left side) from Karachee, Pakistan, ZMH Ot.14.5.1995.3-4 (leg. BMNH 1911.12.6.22-41) and BMNH 1911.12.6.2241. Discussion: Very similar to M. ovatus (see above). Colliculi in this species are completely fused. Distribution: Coasts of the Arabian Peninsula and Makran. Microbuglossus elongatus (DAY 1877) Figs. 792-794 Investigated otoliths: 3 otoliths (left side) from the Persian Gulf, ZMH Ot.14.5.1995.5-6 (leg. BMNH 1928.3.20.1-5) and BMNH 1928.3.20.1-5. Discussion: Otoliths of M. elongatus are easily recognized by their much more deepened sulcus. Distribution: Persian Gulf and coasts of India and Ceylon. Vanstraelenia CHABANAUD 1950 Type-species: Vanstraelenia insignis CHABANAUD 1950 Diagnosis: Moderately thickset to thickset, compressed otoliths; ventral rim deeply and regularly curving, deepest postventrally, dorsal rim nearly straight except for the more or less pronounced predorsal projection, anterior rim ventrally rounded, dorsally joining the predorsal projection, posterior rim blunt, nearly vertically cut, with faint concavity. Index l:h 1.10 to 1.15. Otolith size up to 4 mm. Schwarzhans: Pleuronectiformes 303 786a 787c 787a 786b 789a 791 790 789b 788 792a 794 792c 793 792b Figs. 786-788: Microbuglossus ovatus (RICHARDSON 1846) – 15 × Figs. 789-791: Microbuglossus heini (STEINDACHNER 1902) – 15 × Figs. 792-794: Microbuglossus elongatus (DAY 1877) – 15 × Sulcus somewhat deepened, variable in width, position median to slightly supramedian, anteriorly reduced and not reaching very close to the anterior rim of the otolith. Ostium wider than cauda and somewhat longer. Dorsal and ventral depressions rather wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face completely flat, not very smooth; outer face markedly convex, smooth. Rims mostly thickset. Discussion: The otoliths of the two genera Vanstraelenia and Bathysolea form a morphologically well defined subgroup within the Solea Group. They are characterized by the completely flat inner face and the anteriorly somewhat reduced sulcus. In Bathysolea this character is further developed to form an undivided sulcus with fused colliculi. It is assumed that these two genera represent a lineage endemic to the eastern Atlantic which has originated from near such genera as Microchirus with which it shares the most resemblance. Measurements: chirophthalma insignis l:h h:t 1.10-1.15 2.7-2.9 1.10 2.0 ol:cl 1.4-1.5 1.9 oh:ch 1.1-1.2 1.7 con.o 2.6-3.0 1.6 Side dimorphism: Otoliths of the right side seem to lack the faint concavity at the posterior rim. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Species and distribution: Two species from the tropical West African coast – V. chirophthalma and V. insignis. 304 795a 796a 795c 796b 795b 797b 797c 797a Figs. 795-796: Vanstraelenia chirophthalma (REGAN 1915) – 10 × Fig. 797: Vanstraelenia insignis CHABANAUD 1950 – 10 × Vanstraelenia chirophthalma (REGAN 1915) Figs. 795-796 Investigated otoliths: 2 otoliths (left and right side) from off Lagos, Nigeria, ZMH Ot.14.5.1995.7 (leg. BMNH 1951.3.12.12) and BMNH 1951.3. 12.12. Discussion: Otoliths of V. chirophthalma differ from those of V. insignis in being more thin, showing a less pronounced predorsal projection and a narrower sulcus. Distribution: Tropical coast of West Africa. Vanstraelenia insignis CHABANAUD 1950 Fig. 797 Investigated otoliths: 2 otoliths (left side) from off Nigeria, 4°01’N/7°56’E, BMNH 1962.6.18.125134. Discussion: Otoliths of V. insignis are easily recognized by their much widened ostium, the very thickset appearance and the pronounced predorsal projection. V. insignis was regarded by DESOUTTER (1994) as a synonym of V. chirophthalma. Otoliths, however, seem to indicate that there might indeed be two recent species occurring simultaneously. Distribution: Tropical coats of West Africa. Bathysolea ROULE 1916 Type-species: Solea profundicola VAILLANT 1888 Diagnosis: Moderately thickset to thickset, compressed otoliths with nearly round outline; all rims regularly curving, ventral rim somewhat deeper than dorsal rim. Index l:h 1.00 to 1.20. Otolith size up to 3 mm, diagnostic maturity reached at slightly above 1.0 mm. Schwarzhans: Pleuronectiformes 305 798b 798a 798c 800a 799a 799c 801 800b 799b Fig. 798: Bathysolea profundicola (VAILLANT 1888) – 15 × Figs. 799-801: Bathysolea polonica n.sp. – 15 × Sulcus rather shallow, short and narrow, position slightly supramedian, anteriorly not reaching very close to the anterior rim of the otolith. Ostium and cauda not differentiated and colliculi completely fused. Dorsal and ventral depressions rather wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face almost completely flat, rather smooth; outer face markedly convex, smooth. Rims moderately thickset. Measurements: profundicola †polonica l:h 1.20 1.00-1.15 h:t 2.4 2.6 ol:cl nm nm oh:ch nm nm con.o 2.1 2.5-2.6 Side dimorphism: No data. Discussion: In Bathysolea the sulcus morphology is further reduced than in the related genus Vanstraelenia. Ostium and cauda are completely Piscium Catalogus, Part Otolithi piscium, Vol. 2 fused and so are its colliculi. The outline of the otoliths is much more rounded. Bathysolea no doubt represents the more apomorphic genus in this little subgroup or lineage combining it with Vanstraelenia. Species and distribution: Two recent species from the eastern Atlantic and the western Mediterranean – B. profundicola and B. lactea – and one fossil species from the Miocene of Poland – B. polonica. Bathysolea profundicola (VAILLANT 1888) Fig. 798 syn. Solea greenii GÜNTHER 1889 Investigated otoliths: 1 otolith (left side) from 51°50’N/11°51’W. BMNH 1987.1.21.906. Discussion: This otolith is characterized by the peculiar anteriorly narrowing sulcus. 306 Distribution: Rare, but widely distributed in the eastern Atlantic from Ireland to Angola and in the western Mediterranean from 200 to 1000 m. The second recent species (B. lactea) is endemic to the Cape Verde Islands off West Africa. Discussion: B. polonica resembles well the recent B. profundicola but is somewhat more compressed and does not show that peculiar narrowing of the sulcus anteriorly. Distribution: Middle Miocene of Poland Bathysolea polonica n.sp. Figs. 799-801 7.8.4 Synaptura Group syn. genus Soleidarum sp. 2 – RADWANSKA 1992: pl. 38, figs. 4-6 Genera: Two genera – Austroglossus and Synaptura. Name: After Poland, the only area this species so far has been recorded from. Holotype: Fig. 799, ZPalUW Rak-445. Type-Locality; Korytnica, southern Poland. Age: Badenian, Middle Miocene. Paratypes: 2 otoliths, topo- and stratitypic, ZPalUW Rak-443 (fig. 800) and Rak-444 (fig. 801). Definition and relationship: The otoliths of the two genera in the Synaptura Group are quite elongate for soleids. Inner and outer faces are rather flat, particularly in the horizontal direction, whereas in the vertical direction the inner face may be considerably convex. The cauda is short, less than half the size of the ostium. In Synaptura the ostium shows a tendency towards a bipartite expression. That means, the anterior half of the ostium is somewhat set apart from the posterior half and deepened, thus giving the impression of a sulcus divided into three more or less equally long portions. The elongate shape and the peculiar bipartite ostium found in Synaptura has led me to separate the Synaptura Group from the Solea Group from which it most likely has originated as a specialized offshot. Austroglossus as the more plesiomorphic genus shows some relationship to such otoliths as Solea senegalensis (see respective entry). Synaptura has also been often regarded as related to Zebrias or Brachirus and other genera in the Brachirus and Zebrias Groups. Otolith morphology does not support such a supposed relationship. Diagnosis: Small, compressed otoliths with a roundish outline, a nearly flat inner face and a convex, smooth outer face. Ostium short and narrow, with completely fused colliculi. Inner face with irregularly distributed radial furrows. Description: Outline: Otoliths small, to about 2 mm, with a compressed, nearly circular outline. Ventral rim somewhat deeper than dorsal rim. Otoliths rather thickset. Inner face: Almost completely flat and rather smooth, except for some irregularly distributed radial furrows. Sulcus short, narrow, beginning at some distance from the anterior rim of the otolith, rather shallow and with completely fused colliculi. Circumsulcal depression wide and well developed, but not very deep and with indistinct outer margins. Other views: Rims moderately sharp and smooth. Outer face markedly convex and smooth. Side dimorphism: Not apparent. Ontogeny and Variability: The smallest otoliths available is about 1.2 mm long (fig. 801) but does not differ significantly from the largest one (fig. 799) which is about 2.2 mm long. Also variability seems to be rather restricted. One specimen (fig. ) shows a somewhat more deepened sulcus. Austroglossus REGAN 1920 Type-species: Synaptura pectoralis KAUP 1858 syn. Pseudaustroglossus CHABANAUD 1937 (type-species: P. annectens; hybrid of A. microlepis and Synaptura lusitanica) Diagnosis: Rather thin, large and elongate otoliths; ventral rim moderately deep and regularly curving, dorsal rim nearly straight, with pronounced angles where it meets the anterior and the posterior rims respectively, anterior rim rounded, sometimes with notch above ostium, Schwarzhans: Pleuronectiformes 307 803a 802a 802b 803b 804 802c 803c Figs. 802-804: Austroglossus pectoralis (KAUP 1858) – 10 × posterior rim blunt, nearly vertically cut and somewhat inclined ventrally. Index l:h 1.50 to 1.70. Otolith size up to 6 mm. Sulcus not much deepened and rather wide, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium not wider than cauda, but much longer. Dorsal and ventral depressions rather wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face slightly convex, the postventral portion being somewhat bend outside, not very smooth; outer face almost flat, smooth. Rims mostly thin. Discussion: Of the two genera in the Synaptura Group Austroglossus is the more plesiomorphic one and has not developed the bipartite ostium. Also the straight dorsal rim and the nearly vertically cut posterior rim are typical for this genus. Species and distribution: Two species endemic to the shores of southern Africa (Namibia and Republic of South Africa) – A. pectoralis and A. microlepis. Otoliths of both species have recently been figured in SMALE et al. (1995). Austroglossus pectoralis (KAUP 1858) Figs. 802-804 Measurements: pectoralis l:h 1.50-1.70 h:t 3.0 ol:cl oh:ch 2.3-2.4 about 1.0 Side dimorphism: Not apparent. Variability: Apparently very limited. Piscium Catalogus, Part Otolithi piscium, Vol. 2 con.i 5-6 Investigated otoliths: 3 otoliths (2 left side and 1 right side) from Natal, South Africa, ZMH Ot.14.5.1995.8-9 (leg. BMNH 1905.6.8.29-30) and BMNH 1905.6.8.29-30. Distribution: South Africa, from the Cape of Good Hope to Natal. 308 806a 805a 806b 805b 807a 807c 807b Figs. 805-806: Synaptura commersoniana CANTOR 1849 – 15 × Fig. 807: Synaptura albomaculata (KAUP 1858) – 15 × Synaptura CANTOR 1849 Type-species: Synaptura commersoniana CANTOR 1849 Side dimorphism: Otoliths of the left side seem to have a slightly more convex inner face and the postventral area is more gently curving. Diagnosis: Rather thin, moderately large and elongate otoliths; ventral rim not very deep and regularly curving, dorsal rim shallow, often with pronounced angle where it meets the posterior rim, sometimes developed as pointed spine, anterior rim more rounded, with angular ‘rostrumlike’ tip at height of the sulcus, posterior rim blunt, ventrally inclined. Index l:h 1.55 to 2.00. Otolith size up to about 5.5 mm. Sulcus usually deepened and rather wide, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium wider and much longer than cauda, bipartite with the anterior half being deepened and the posterior half being wider. Dorsal and ventral depressions moderately wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face slightly convex, not very smooth; outer face almost flat, rather smooth. Rims mostly sharp. Ontogeny and variability: Smaller otoliths are more gently curving in outline (see figures in CHAINE, 1937). Variability as it seems is very restricted. Species and distribution: Five nominally valid species – S. commersoniana and S. albomaculata from the Indian Ocean, S. marginata from South Africa, S. cadenati from West Africa and S. lusitanica along the coasts of West Africa and Portugal. Synaptura commersoniana CANTOR 1849 Figs. 805-806 syn. Solea russellii BLEEKER 1852 Measurements: l:h h:t commersoniana 1.55-1.65 2.3-2.4 albomaculata 1.65 2.8 lusitanica 1.85-2.00 2.0-2.8 Discussion: Otoliths of the genus Synaptura are easily recognized by their elongate shape and the bipartite ostium. Both characters are least developed in S. commersoniana which is probably the most plesiomorphic species in this genus. ol:cl 2.0-2.5 2.8 2.0-2.2 oh:ch 1.1-1.2 1.3 1.35-1.5 con.i 3.5-4.0 3.2 3.0-4.0 Investigated otoliths: 2 otoliths (left and right side) from Karachee, Pakistan, ZMH Ot.14.5. 1995.10 (leg. BMNH 1911.12.6.19-21) and BMNH 1911.12.6.19-21. Schwarzhans: Pleuronectiformes 309 809a 808a 808c 809b 808d 808b 811a 810 811b Figs. 808-811: Synaptura lusitanica CAPELLO 1868 – 10 × Discussion: The otoliths of S. commersoniana exhibit the most plesiomorphic pattern of the species in this genus with only an incipient bipartite ostium and a rather low index l:h. Distribution: Eastern Atlantic from Portugal to the Congo river mouth and in the western Mediterranean. Synaptura albomaculata (KAUP 1858) Fig. 807 Investigated otoliths: 1 otolith (left side) from southern India, BMNH 1969.3.27.1-2. Discussion: In this species the ostium is distinctly bipartite. It differs from S. lustanica by the lower index l:h and the lack of a postdorsal spine. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Indian Ocean from Oman to Singapore. Synaptura lusitanica CAPELLO 1868 Figs. 808-811 syn. Synaptura punctatissima PETERS 1877 Investigated otoliths: 4 otoliths (2 left side and 2 right side) from Senegal, IRSNB (coll. Nolf). Discussion: Like S. albomaculata otoliths of S. lusitanica show a distinctly bipartite ostium, but they are more elongate and with a sharp postdorsal spine. Distribution: Eastern Atlantic from Portugal to the river Congo mouth and western Mediterranean. 310 7.8.5 Brachirus Group Genera: Four genera – Heterobuglossus, Dexillichthys, Brachirus, Anisochirus and Phyllichthys. Definition and relationship: The otoliths of the five genera in the Brachirus Group are morphologically intermediate between those of the Solea Group, from which they have derived most likely, and the apomorphic Zebrias Group. Its combine may not be entirely natural. The two more plesiomorphic genera – Heterobuglossus and Dexillichthys – could also be placed in the Solea Group, Brachirus, Anisochirus and Phyllichthys could be regarded as the most ‘primitive’ members of the Zebrias Group. The common character found in the members of this group is an expansion of the postventral portion, a rather shallow ventral rim and a reduction of the postdorsal portion (at least in most species). This is even more so developed in the genera of the Zebrias Group. Unlike in otoliths of the Zebrias Group, however, the sulcus is not reduced anteriorly and neither are the colliculi fused. All in all, otoliths of the Brachirus and the Zebrias Groups often look like being placed upside down. Heterobuglossus CHABANAUD 1931 Type-species: Synaptura aspilos BLEEKER 1851 Diagnosis: Moderately thickset, compressed otoliths with rounded rectangular outline; ventral and dorsal rims regularly curving but shallow, somewhat undulating, anterior rim broadly rounded or blunt, posterior rim blunt, slightly concave, postventral and postdorsal projections nearly equal in expression. Index l:h 1.00 to 1.15. Otolith size up to nearly 3 mm. Sulcus somewhat deepened and rather narrow, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium not wider than cauda, but much longer. Dorsal and ventral depressions moderately wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims moderately sharp. Measurements: aspilos l:h 1.00-1.15 h:t 3.0 ol:cl 1.4-1.8 oh:ch 0.95-1.1 con.i 2.6 Side dimorphism: Not apparent. Variability: Variability in this genus seemingly is restricted to minor variations of the outline and the sulcus proportions. Discussion: Heterobuglossus is the most plesiomorphic genus in this group and could also be regarded as a member of the Solea Group. Characteristic is its rounded rectangular outline and the rather shallow ventral rim. Species and distribution: Heterobuglossus is a monospecific genus with H. aspilos distributed from Malaysia through Indonesia to northern Australia. Heterobuglossus aspilos (BLEEKER 1851) Figs. 812-814 syn. Synaptura marmorata BLEEKER 1853 syn. Synaptura heterolepis BLEEKER 1856 Investigated otoliths: 3 otoliths (2 left side and 1 right side) from Singapore, ZMH Ot. 14.5.1995.11-12 (leg. BMNH 1933.7.31.21-22) and BMNH 1933.7.31.21-22. Dexillichthys (WHITLEY 1931) Type-species: Synaptura macrolepis BLEEKER 1958 syn. Dexillus CHABANAUD 1930 (pre-occupied; type-species: S. macrolepis) syn. Whitleyia CHABANAUD 1930 (pre-occupied; type-species: Synaptura setifer) syn. Paradicula WHITLEY 1931 (type-species: Synaptura setifer) syn. Strandichthys WHITLEY 1937 (type-species: Synaptura muelleri) syn. Mischommatus CHABANAUD 1938 (typespecies: Synaptura muelleri) Diagnosis: Moderately thickset, compressed otoliths; ventral rim moderately deep, deepest posteriorly, dorsal rim more shallow, somewhat undulating, anterior rim rounded, posterior rim Schwarzhans: Pleuronectiformes 311 812a 812b 812c 813 812d 814 Figs. 812-814: Heterobuglossus aspilos (BLEEKER 1851) – 15 × blunt, nearly vertically cut, postventral projection more pronounced than angular postdorsal projection. Index l:h 1.25. Otolith size up to about 4 mm. Sulcus very shallow and narrow, position nearly median, anteriorly somewhat reduced and not reaching very close to the anterior rim of the otolith. Ostium slightly wider than cauda and much longer. Dorsal and ventral depressions rather wide, with indistinct outer margins, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face nearly flat, not very smooth; outer face almost flat, centrally concave and rather smooth. Rims mostly thickset. Measurements: macrolepis l:h 1.25 h:t 2.6 ol:cl 2.9 oh:ch con.i 1.4 about 10 Side dimorphism: No data. Discussion: Dexillichthys is only tentatively placed in this group. The otoliths are characterized by the nearly flat inner face with the very shallow sulcus, the extremely small cauda and the anteriorly reduced ostial opening. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Species and distribution: Three species from the Indonesian Archipelago, the Philippines and northern Australia – D. macrolepis, D. muelleri and D. setifer. Dexillichthys macrolepis (BLEEKER 1858) Fig. 815 Investigated otoliths: 1 otolith (left side) from the Kumai river, SW Borneo, BMNH 1933.3.11-11a. Distribution: The Gulf of Bengal and Borneo. Brachirus SWAINSON 1839 Type-species: Pleuronectes orientalis BLOCH & SCHNEIDER 1801 syn. Achiroides BLEEKER 1851 (type-species: Plagusia melanorhynchus) syn. Euryglossa KAUP 1858 (type-species: Pleuronectes orientalis) syn. Eurypleura KAUP 1858 (type-species: Plagusia melanorhynchus) syn. Barbourichthys CHABANAUD 1933 (typespecies: Barbourichthys zanzibaricus) 312 c a d b Fig. 815: Dexillichthys macrolepis (BLEEKER 1858) – 10 × syn. Trichobrachirus CHABANAUD 1943 (typespecies: Synaptura villosa) syn. Achlyopa WHITLEY 1947 (type-species: Synaptura nigra) Diagnosis: Thin to moderately thickset, compressed otoliths; ventral rim shallow, regularly curving, postventral projection usually well developed, dorsal rim less shallow, sometimes with postdorsal angle, anterior rim broadly rounded, posterior rim blunt, cut, ventrally or (less common) dorsally inclined. Index l:h 1.05 to 1.30. Otolith size up to about 3 mm, diagnostic maturity probably reached early at about 1.2 to 1.5 mm. Sulcus moderately deep and moderately wide, position more or less median, anteriorly reaching close to the anterior rim of the otolith. Ostium slightly wider than cauda, but much longer. Dorsal and ventral depressions not very wide, slightly deepened and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth or slightly ornamented. Rims mostly sharp. Measurements: l:h h:t orientalis 1.10 3.4-3.8 niger 1.15 nd cinerascens 1.20-1.30 3.0 pan 1.05 2.4 melanorhynchus 1.25 nd ol:cl 1.9-2.6 1.8-2.0 1.8-2.0 1.6 2.0 oh:ch 1.2-1.3 1.1-1.2 1.2-1.3 1.2 1.3 con.i 2.6-2.8 nd 3.0 3.0 nd Side dimorphism: Otoliths of the right side may have a slightly stronger convex inner face than those of the left side. Ontogeny and variability: In B. cinerascens smaller otoliths are slightly more compressed than larger ones. The level of variations is rather moderate, except for the index ol:cl which seems to variate quite considerably. Discussion: Most species of the genus Brachirus show the ventrally inclined posterior rim and a tendency to fuse the colliculi. These characters are further developed in the Zebrias Group and in fact Brachirus could also be regarded as the most ‘primitive’ member of that group. More intermediate even are ovally shaped otoliths of the related genera Anisochirus and Phyllichthys (see respective entries). Most members of the Zebrias Group show completely fused colliculi and except for the genus Aesopia, a somewhat reduced sulcus opening. Species and distribution: Brachirus is a species rich genus in the Indo-West-Pacific, but apparently in need of revision. The following list of nominally valid species thus may not be complete – B. annularis, B. breviceps, B. cinerascens, B. melanorhynchus, B. orientalis, B. nigra, B. pan, B. salinarum, B. selheimi, B. villosa, B. zanzibarica. B. panoides is tentatively being excluded from the genus and placed in a genus of its own – Anisochirus (see respective entry). Many species of Brachirus are known to invade upstream into rivers, some are exclusively freshwater. Brachirus orientalis (BLOCH & SCHNEIDER 1801) Figs. 816-817 syn. Solea foliacea RICHARDSON 1840 syn. Solea trichodactylus KAUP 1858 syn. Brachirus sundaicus BLEEKER 1866 Schwarzhans: Pleuronectiformes 313 817b 816a 817c 817b 816b 818 819 Figs. 816-817: Brachirus orientalis (BLOCH & SCHNEIDER 1801) – 10 × Figs. 818-819: Brachirus niger (MACLEAY 1881) – 15 × Investigated otoliths: 2 otoliths (left and right side) from off Pakistan, IRSNB (coll. Nolf). Brachirus niger (MACLEAY 1881) Figs. 818-819 Discussion: A species with the typical outline of otoliths of the Brachirus Group. The otoliths are relatively compressed and the sulcus is rather narrow. Investigated otoliths: 2 otoliths (left and right side) from off Sydney, Australia, ZMH Ot.20.5. 1995.1 (leg. BMNH 1890.9.23.226-8) and BMNH 1890.9.23.226-8. Distribution: Makran Coast, Pakistan, to China. Discussion: This species is remarkable for its pronounced postdorsal angle. Distribution: Coasts of northern Australia. Piscium Catalogus, Part Otolithi piscium, Vol. 2 314 Brachirus cinerascens GÜNTHER 1862 Figs. 820-822 Anisochirus GÜNTHER 1862 Type-species: Synaptura panoides BLEEKER 1851 Investigated otoliths: 3 otoliths (left side) from Basra, Iraq, ZMH Ot.20.5.1995.2-3 (leg. BMNH 1920.3.3.290-6) and BMNH 1920.3.3.290-6. syn. Chabanaudetta WHITLEY 1931 (unneeded substitute for Anisochirus) Discussion: Similar to B. orientalis and often regarded as synonymous, but otoliths more elongate and delicately ornamented. Distribution: Persian Gulf; also recorded from Ceylon. Brachirus pan (HAMILTON-BUCHANAN 1822) Fig. 823 Investigated otoliths: 1 otolith (left side) from the Sunderabands, Bangla Desh, BMNH 1928.3.20. 15-17. Discussion: Otoliths compressed with a rather flat inner face and a very wide sulcus. Distribution: Coasts of eastern India and Malaysia; entering rivers. Brachirus melanorhynchus (BLEEKER 1850) Fig. 824 syn. Achiroides leucorhynchus BLEEKER 1851 syn. Solea harmandi SAUVAGE 1878 Investigated otoliths: 1 somewhat eroded, probably juvenile otolith (right side) from Singapore, BMNH 1984.1.18.263. Discussion: Judging from the poorly preserved and small, probably juvenile specimen available, it is an otolith with a strong postdorsal angle and a wide sulcus. Distribution: Freshwater of Malaysia, Indochina, Java, Sumatra and Borneo. Diagnosis: Rather thin, oval otoliths; ventral rim shallow and regularly curving, dorsal rim somewhat reduced, also rather shallow, anterior rim rounded, posterior rim too, but more broadly so. Index l:h about 1.3. Otolith size small, not much exceeding 2 mm. Sulcus moderately deep, rather narrow and short, terminating at some distance from the posterior tip of the otolith, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium slightly wider than cauda, but much longer. Colliculi separated. Dorsal and ventral depressions rather narrow, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face convex, smooth; outer face almost flat, smooth or slightly ornamented. Rims sharp. Measurements: panoides l:h about 1.3 h:t nm ol:cl 1.8 oh:ch 0.95 con.i nm Side dimorphism: No data. Discussion: I have selected to keep this monospecific genus separate from Brachirus, where it is usually placed, because of its intermediate otolith morphology between Brachirus and Phyllichthys. From the letter it merely differs in the more clearly separated colliculi. The short sulcus and the oval outline relate it to Phyllichthys. Species and distribution: Anisochirus presumably is a monospecific genus with A. panoides known from the Indo-Malaysian Archipelago. Anisochirus panoides (BLEEKER 1851) Fig. 825 Investigated otoliths: 1 otolith, eroded along the dorsal rim (left side) from Bangkok, BMNH 1928.5.22.1. Discussion: Judging from the somewhat eroded otolith available A. panoides similar to P. puncta- Schwarzhans: Pleuronectiformes 315 820c 822 820a 821 820b 823b 824 823a 823b Figs. 820-822: Brachirus cinerascens GÜNTHER 1862 – 10 × Fig. 823: Brachirus pan (HAMILTON-BUCHANAN 1922) – 15 × Fig. 824: Brachirus melanorhynchus (BLEEKER 1850) – 15 × tus (see below), but with more clearly separated colliculi. Inner face convex, smooth; outer face almost flat, smooth or slightly ornamented. Rims sharp. Distribution: Indochina, Sumatra and Borneo, entering freshwater. Measurements: punctatus Phyllichthys MCCULLOCH 1916 Type-species: Synaptura sclerolepis MACLEAY 1878 Diagnosis: Rather thin, oval otoliths; ventral rim shallow and regularly curving, dorsal rim somewhat reduced, also rather shallow, anterior rim rounded, posterior rim too, but more broadly so. Index l:h 1.45. Otolith size small, not much exceeding 2 mm. Sulcus moderately deep, rather narrow and short, terminating at some distance from the posterior tip of the otolith, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium slightly wider than cauda, but much longer. Ostium nearly fused with cauda. Dorsal and ventral depressions rather narrow, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Piscium Catalogus, Part Otolithi piscium, Vol. 2 l:h 1.45 h:t nm ol:cl 2.6 oh:ch 1.2 con.i nm Side dimorphism: No data. Discussion: CHABANAUD (1939) placed Phyllichthys close to Zebrias (see Zebrias Group). Their otoliths morphologically perfectly close the gap between the genera of the Brachirus and the Zebrias Group. Phyllichthys is particularly close to Anisochirus (see above). The ventrally pronounced outline of the otolith and the short sulcus resemble otoliths of the Zebrias Group, whereas the faint separation of the colliculi and the close approach of the sulcus to the anterior rim is similar to other genera in the Brachirus Group. Phyllichthys (and also Anisochirus) thus could also be regarded as the most plesiomorphic genus of the Zebrias Group. Species and distribution: CHABANAUD (1939) listed three species from the warm waters of Australia – P. sclerolepis, P. punctatus and P. sejunctus. 316 825 826 Fig. 825: Anisochirus panoides (BLEEKER 1851) – 15 × Fig. 826: Phyllichthys punctatus MCCULLOCH 1916 – 15 × Phyllichthys punctatus MCCULLOCH 1916 Fig. 826 Investigated otoliths: 2 otoliths, somewhat eroded by formalin (left and right side) from Western Australia, off Singletown Beach, 32°27’S/ 115°45’E, ZMH Ot.20.5.1995.4-5 (leg. WAM-P 28397-003). Distribution: Western Australia. 7.8.6 Zebrias Group Genera: This group contains at least 5 recent genera – Aesopia, Pseudaesopia, Soleichthys, Zebrias and Typhlachirus. Except for the latter, otoliths are known from all of these. Recommendation is made to separate the two species of the genus Soleichthys and erect a new genus for Soleichthys microcephalus should other ichthyological investigations support the otolith analysis. Phyllichthys and Anisochirus of the Brachirus Group could also be placed in this group (see respective entries). Finally, one newly erected fossil genus – Granulithus – is also included in this group. The ending -lithus is chosen to indicate that it represents an otolith based genus. Definition and relationship: The otoliths of this group of fishes, which are often found in near coralline environments, are characterized by otoliths with a set of synapomorphic features. These are the ventrally pronounced outline and the deep sulcus with completely fused colliculi (except for “Soleichthys” microcephalus). Also the sulcus is rather short, terminating at some distance from the posterior rim and also from the anterior rim of the otolith (except for Aesopia and Granulithus). The Zebrias Group clearly represents a specialized offshot from the Brachirus Group. A morphologically intermediate genus as far as otoliths are concerned is Phyllichthys. Phyllichthys is placed here in the Brachirus Group (see respective entry) but could also be regarded as the most plesiomorphic genus of the Zebrias Group. Aesopia KAUP 1858 Type-species: Aesopia cornuta KAUP 1858 syn. Coryphaesopia CHABANAUD 1930 (typespecies: A. cornuta) Diagnosis: Moderately thin, rather elongate and ovally shaped otoliths; ventral rim shallow, broad, dorsal rim more rounded, short, without angles, anterior and posterior rims rounded. The otolith looks like turned upside down. Index l:h 1.55 to 1.65. Otolith size small, not exceeding much 2.5 mm. Sulcus deepened, wide, anteriorly reaching relatively close to the anterior rim of the otolith, posteriorly terminating at some distance from the posterior rim of the otolith. Ostium and cauda completely fused, and so are the colliculi. Dorsal and ventral depressions rather narrow, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face slightly convex, not very smooth; outer face almost flat, smooth. Rims moderately thickset. Measurements: cornuta l:h h:t 1.55-1.65 2.5-2.7 ol:cl – oh:ch – con.i 3.5-4.2 Side dimorphism: Not apparent. Variability: Details of the outline and the width of the sulcus seem to variate slightly. Discussion: Otoliths of Aesopia differ somewhat from those of the other genera in the Zebrias Group. They are rather elongate and, most important, the sulcus still reaches close to the anterior tip of the otolith. Species and distribution: Aesopia is a monospecific genus with A. cornuta widely distributed through the Indo-West Pacific. Schwarzhans: Pleuronectiformes 317 827a 829a 828 827c 829b 827b Figs. 827-829: Aesopia cornuta KAUP 1858 – 15 × Aesopia cornuta KAUP 1858 Figs. 827-829 Measurements: †granum syn. Coryphaesopia barnardi CHABANAUD 1934 Investigated otoliths: 3 otoliths (2 left and 1 right side) from the Ganjam coast, India, ZMH Ot.20.5.1995.6-7 (leg. BMNH 90.12.4.10-11) and BMNH 90.12.4.10-11. Distribution: South Africa through the Indian Ocean to the West Pacific (Japan). †Granulithus n.gen. Type-species: Aesopia granum SCHWARZHANS 1994. Name: By tautonomy from the type-species; ending -lithus indicates it being an otolith based fossil genus. Diagnosis: A fossil, otolith based genus of the family Soleidae, subfamily Soleinae, Zebrias otolith group with the following characters. The otoliths are very small, not exceeding 1.5 mm, compact and rather thickset. Outline is moderately elongate, ovally, somewhat variable. Sulcus moderately wide to wide, very deep, with completely fused colliculi, short, terminating at some distance from the posterior rim of the otolith, but anteriorly reaching relatively close to the anterior tip of the otolith. Circumsulcal depression narrow, rather shallow, but well developed around caudal tip of sulcus. Inner and outer faces moderately convex and smooth. Rims rather thickset. Piscium Catalogus, Part Otolithi piscium, Vol. 2 l:h h:t 1.40-1.80 2.2-2.4 ol:cl – oh:ch – con.i 3.2-3.8 Side dimorphism: Not apparent. Variability: Outline and width of the sulcus are quite variable. Discussion: Granulithus is quite similar to Aesopia in which it has originally been placed. It is in particular the deep sulcus, which closely reaches to the anterior tip of the otolith which both genera share. However, the compact appearance and the extremely deepened sulcus are quite distinctive and represent the main reasons to separate the fossil from the recent genus. Species and distribution: Granulithus is a monospecific genus with G. granum exclusively known from the Upper Oligocene of northern Germany. There it occurs in a near shore rocky subtidal pool environment. Granulithus granum (SCHWARZHANS 1994) Figs. 830-833 syn. Aesopia granum SCHWARZHANS 1994 – SCHWARZHANS 1994: figs. 529-532 Investigated otoliths: 4 otoliths (1 left, 3 right side) including the holotype (fig. 830) and the paratypes (figs. 831-833) from the Upper Oligocene of Ratingen near Düsseldorf, northern Germany. Distribution: Upper Oligocene of northern Germany, known only from the type-locality. 318 832a 830a 830c 833 831 832b 830b Figs. 830-833: Granulithus granum (SCHWARZHANS 1994) – 15 × Soleichthys BLEEKER 1860 Type-species: Solea heterorhinos BLEEKER 1856 Diagnosis: Moderately thin, compressed, ovally shaped otoliths; ventral rim shallow, broad, dorsal rim more rounded, short, without angles, anterior rim rounded, posterior rim blunt or rounded. All rims somewhat undulating. The otolith looks like turned upside down. Index l:h about 1.30. Otolith size rather small, probably not exceeding much 3 mm. Sulcus deepened, wide, anteriorly reduced, posteriorly terminating at some distance from the posterior rim of the otolith. Ostium and cauda completely fused, and so are the colliculi. Dorsal and ventral depressions moderately wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face convex, not very smooth; outer face almost flat, smooth. Rims sharp to moderately thickset. Measurements: microcephalus heterorhinos l:h 1.10-1.15 1.30 h:t 2.9 3.5 ol:cl 1.5-1.6 – oh:ch 1.05-1.20 – con.i 3.0 2.7 Side dimorphism: Not apparent in S. heterorhinos. In “S.” microcephalus otoliths of the left side show separated colliculi, whereas in otoliths of the right side they are practically fused. Variability: Apparently very limited. Discussion: Otoliths of S. heterorhinos resemble those of the genus Aesopia in outline and general appearance. However, the sulcus is anteriorly reduced and the otolith itself more compressed. – “S”. microcephalus resembles more otoliths of Pseudaesopia in its more rectangular outline. A very plesiomorphic character for a member of the Zebrias Group found in this species is the separation of the colliculi (particularly so in otoliths of the left side). All in all, otoliths of “S”. microcephalus differ significantly from the type-species of Soleichthys – S. heterorhinos – and it is because of that that I suggest to place it in a separate genus altogether, provided other ichthyological analyses support the otolith findings. “S”. microcephalus seemingly represents one of the most plesiomorphic species in the Zebrias Group characterized by its separated colliculi. It has probably given rise to the genera Pseudaesopia and Zebrias. Species and distribution: Traditionally, two species have been placed in this genus – S. heterorhinos widely distributed throughout the Indo-West Pacific and “S”. microcephalus from southern Australia. Recently, S. siammakuti has been described from the Gulf of Thailand. Soleichthys heterorhinos (BLEEKER 1856) Fig. 834 syn. Aesopia multifasciata KAUP 1858 syn. Solea nigrostriolata STEINDACHNER & KNER 1870 syn. Solea tubifera PETERS 1876 syn. Solea lineata RAMSAY 1883 ?syn. Solea borbonica REGAN 1905 Investigated otoliths: 1 otolith (left side) from the Oualau atoll, BMNH 79.5.14.65. Discussion: See entry to genus. Distribution: Indo-West Pacific from the Isle of Mauritius to Australia and the Philippines. Schwarzhans: Pleuronectiformes 319 “Soleichthys” microcephalus GÜNTHER 1862 Figs. 835-837 Investigated otoliths: 3 otoliths (2 left side, figs. 835, 837 and 1 right side, fig. 836) from Port Jackson, Australia, ZMH Ot.20.5.1995.8-9 (leg. BMNH 90.9.23.56-60) and BMNH 90.9.23.56-60. a c Discussion: See entry to genus. Distribution: Coasts of southern temperate Australia. b Fig. 834: Soleichthys heterorhinus (BLEEKER 1856) – 15 × Pseudaesopia CHABANAUD 1934 Type-species: Aesopia regani GILCHRIST 1906 Diagnosis: Moderately thin, compressed otoliths with rounded rectangular outline; ventral rim shallow, broad, dorsal rim more rounded, short, with rounded medio- and postdorsal angles, anterior rim rounded, posterior rim blunt, high, nearly vertically cut. The otolith looks like turned upside down. Index l:h 1.15 to 1.30. Otolith size small, not exceeding much 2.5 mm. Sulcus deepened, wide, anteriorly reduced, posteriorly terminating at some distance from the posterior rim of the otolith. Ostium and cauda completely fused, and so are the colliculi. Dorsal and ventral depressions rather narrow, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face convex, not very smooth; outer face almost flat, smooth. Rims sharp. Measurements: japonica l:h 1.15-1.30 h:t 3.0 con.i 2.3 Variability: Except for the proportions of the otolith intraspecific variability seems to be very limited. 835c 835b 837 Figs. 835-837: “Soleichthys” microcephalus GÜNTHER 1862 – 15 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 oh:ch – Side dimorphism: Not apparent. 836 835a ol:cl – 320 839 838c 838a 838b 841 840 Figs. 838-841: Pseudaesopia japonica (BLEEKER 1860) – 15 × Discussion: Otoliths of the genus Pseudaesopia very closely resemble those of the genera Zebrias and Soleichthys. In fact, similarity with Zebrias is so close that based on otoliths Pseudaesopia would better be regarded as a subgenus only. Within the genus Soleichthys “S”. microcephalus is closest, merely differing in the separation of the colliculi (see respective entry for further discussion). syn. Nematozebrias CHABANAUD 1943 (typespecies: Aesopia quagga) syn. Strabozebrias CHABANAUD 1943 (type-species: Synaptura cancellata) Investigated otoliths: 4 otoliths (3 left and 1 right side) from the Inland Sea of Japan, ZMH Ot.20.5.1995.10-12 (leg. BMNH 1905.6.6.213-222) and BMNH 1905.6.6.213-222. Diagnosis: Thin to moderately thickset, compressed otoliths with rounded rectangular outline; ventral rim shallow, broad, dorsal rim more rounded, with rounded pre- and postdorsal angles, anterior and posterior rims blunt, high, nearly vertically cut. The otolith looks like turned upside down. Index l:h 1.15 to 1.30. Otolith size moderate, not exceeding much 3.5 mm. Sulcus deepened, narrow or wide, very short, anteriorly reduced, posteriorly terminating at some distance from the posterior rim of the otolith. Ostium and cauda completely fused, and so are the colliculi. Dorsal and ventral depressions moderately wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face convex, not very smooth; outer face almost flat, smooth. Rims sharp. Distribution: Japan. Measurements: Zebrias JORDAN & SNYDER 1900 Type-species: Pleuronectes zebra BLOCH 1785 altipinnis synapturoides cancellatus zebrias quagga Species and distribution: Pseudaesopia contains three species – P. regani from South Africa, P. japonica from Japan and P. crossolepis from China. Pseudaesopia japonica (BLEEKER 1860) Figs. 838-841 syn. Zebrias smithii SMITH & POPE 1906 l:h 1.25 1.05-1.10 1.20-1.30 1.30 1.20-1.25 h:t 3.0 3.1 3.5 4.0 nm ol:cl – – – – – oh:ch – – – – – con.i 3.3 2.6 3.0 4.5 nm syn. Holonodus CHABANAUD 1936 (type-species: Synaptura synapturoides) syn. Haplozebrias CHABANAUD 1943 (type-species: Synaptura fasciata) Schwarzhans: Pleuronectiformes 321 842c 842a 843 842b Figs. 842-843: Zebrias altipinnis (ALCOCK 1890) – 15 × Side dimorphism: Otoliths of the left side usually show a wider sulcus than those of the right side. Also sometimes left hand otoliths exhibit an incipient separation into ostium and cauda (although colliculi are always fused) or sometimes are slightly more compressed than those of the right side. Species and distribution: Zebrias contains about 14 nominally valid species mostly from the Indian Ocean – Z. altipinnis, Z. annadalei, Z.cancellatus, Z. cochinensis, Z. craticulus, Z. fasciatus, Z. keralensis, Z. lucapensis, , Z. munroi, Z. penescalaris, Z. quagga, Z. scalaris, Z. synapturoides and Z. zebra. Discussion: Zebrias has been separated into various genera or subgenera depending on the authors views. At this stage the mosaic pattern of the otolith morphology does not support such a concept. Nevertheless, it seems that two slightly different morphologies could possibly be distinguished and could eventually be attributed to two separate genera or subgenera. At first, there is a group of species with otoliths nearly rectangular in outline containing Z. altipinnis, Z. synapturoides and Z. cancellatus. Those closely resemble Pseudaesopia and may even be placed in that genus. But also “Soleichthys” microcephalus is very similar except for the separated colliculi in that species. The second group shows anteriorly narrowed otoliths which are rather thin and have a more flat inner face. This species group contains Z. zebra and Z. quagga. Zebrias altipinnis (ALCOCK 1890) Figs. 842-843 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 2 otoliths (1 left and 1 right side) from the river Hughli, India, ZMH Ot.20.5. 1995.13 (leg. BMNH 1928.3.20.29-30) and BMNH 1928.3.20.29-30. Discussion: This species is remarkable for the incipient distinction into ostium and cauda in otoliths of the left side. In this respect it resembles “Soleichthys” microcephalus, although there even the colliculi are separated. Otolith morphology suggests that Z. altipinnis probably is the most plesiomorphic species in the genus. Distribution: India and Malaysia. 322 844c 845 844a 844b 846b 846a 847 Figs. 844-845: Zebrias synapturoides (JENKINS 1910) – 15 × Figs. 846-847: Zebrias cancellatus MCCULLOCH 1916 – 15 × Zebrias synapturoides (JENKINS 1910) Figs. 844-845 Zebrias zebra (BLOCH 1785) Fig. 848 syn. Solea jerreus CUVIER 1829 syn. Solea ommatura RICHARDSON 1845 Investigated otoliths: 2 otoliths (left and right side) from the Ganjam coast, India, ZMH Ot.20.5. 1995.14 (leg. BMNH 1928.3.20.23-25) and BMNH 1928.3.20.23-25. Investigated otoliths: 1 otolith (left side), without location, BMNH 74.1.16.39. Discussion: Otoliths of Z. synapturoides are very compressed and those of the left side show an extremely widened sulcus. Discussion: Otoliths of Z. zebra are readily recognized by its anteriorly narrowed outline. Distribution: Widely distributed from Indonesia to China and Japan. Distribution: India. Zebrias quagga (ALCOCK 1890) Figs. 849-850 Zebrias cancellatus MCCULLOCH 1916 Figs. 846-847 Investigated otoliths: 2 otoliths (left and right side) from Shark Bay, Western Australia, 25°21’S/ 113°44’E, ZMH Ot.20.5.1995.15-16 (leg. WAM-P 28624-001). Discussion: Similar to Z. synapturoides, but more elongate and with a very regular rectangular outline. Investigated otoliths: 2 somewhat eroded, juvenile otoliths (left side) from the Persian Gulf, BMNH 1911.2.23.53-57. Discussion: The otoliths available from Z. quagga are too small and poorly preserved to allow reliable analysis. It seems that they are basically similar to Z. zebrias. Distribution: Widely distributed from the Persian Gulf to China and the Sea of Java. Distribution: Western Australia. Schwarzhans: Pleuronectiformes 323 849 848a 848c 848b 850 Fig. 848: Zebrias zebra (BLOCH 1785) – 15 × Figs. 849-850: Zebrias quagga (ALCOCK 1890) – 15 × Typhlachirus HARDENBERG 1931 Type-species: Synaptura lipophthalma JANOS 1881 syn. Cryptops HARDENBERG 1931 (type-species: C. caeca; syn. T. lipophthalma) Remarks: Otoliths of Typhlachirus have not been available for investigation. A specimen in the BMNH collection was found to have its otoliths dissolved by formalin. Typhlachirus is thought to be related to Brachirus and/or Zebrias (CHABANAUD, 1948). Species and distribution: Typhlachirus is known from two species – T. lipophthalmus from Borneo and T. sorsogonensis from the Philippines – both of which have been collected very rarely. inner face and the shallow sulcus. In contrast to the otoliths of the Heteromycteris Group the circumsulcal depression (well connected around the cauda) runs relatively close to the rims of the otoliths and is often very narrow, sometimes reduced to a furrow only. Also the cauda is not enlarged. The otoliths of the Pardachirinae bear close resemblance to the Cynoglossidae and it is quite probable that the Cynoglossidae have derived from them. Cynoglossid otoliths are characterized by the unique widened cauda and the fused colliculi resulting in a “hammer” shaped sulcus. This pattern is already foreshadowed in the Heteromycteris Group (see respective entries). On the other hand Cynoglossidae share the narrow circumsulcal depression which runs close to the otolith rims with the Pardachirus Group. Pardachirinae 7.8.7 Pardachirus Group Genera: The Pardachirus Group contains three recent genera – Aseraggodes, Pardachirus (with Liachirus as a junior synonym) and Parachirus – and two newly erected fossil otolith based genera from the European Eocene – Praearchirolithus and Pseudopardachirolithus. The two fossil records from Eocene times prove the ancient origin not only of the Soleidae but also of the subfamily Pardachirinae, which in many respects is the most apomorphic subfamily of the Soleidae. Definition and relationship: The otoliths of the Pardachirus Group like those of the related Hetromycteris Group are characterized by their compressed, high bodied outline, the smooth convex Piscium Catalogus, Part Otolithi piscium, Vol. 2 †Praearchirolithus n.gen. Type-species: genus Soleidarum schultzei NOLF & LAPIERRE 1979 Name: A combination of prae (lat. = early) and the generic name Achirus; ending -lithus indicates it being an otolith based fossil genus. Diagnosis: A fossil otolith based genus of the family Soleidae, subfamily Pardachirinae, Pardachirus Group with the following characters. The otoliths are small, not exceeding 1.5 mm, compact, moderately thickset and with an almost circular outline. Ventral rim deeply and regularly curving, dorsal rim flat, with pre- and postdorsal angles. They represent the only genus in the group with an index l:h of more than 1.0. The sulcus is narrow, slightly deepened, particularly so the 324 851a 851c 852 853a 851b 853b Figs. 851-853: Praearchirolithus schultzei (NOLF & LAPIERRE 1979) – 25 × small cauda. Inner face otherwise rather smooth and moderately convex. Circumsulcal depression narrow, running close to the rims of the otolith. Rims rather thickset. Outer face smooth, slightly convex. olles, France, coll. IRSNB. Measurements: Aseraggodes KAUP 1858 Type-species: Aseraggodes guttulatus KAUP 1858 †schultzei l:h h:t 1.05-1.10 2.6-2.8 ol:cl 1.7-2.1 oh:ch 1.0-1.25 con.i 2.4-2.5 Side dimorphism: Not apparent. Variability: Very limited to details of the outline, especially the expression of the dorsal rim, and minor modifications of the sulcus proportions. Discussion: Praearchirolithus no doubt represents the most “primitive” genus in the Pardachirus Group evidenced by the high index l:h and the simple character status of sulcus and otolith outline. Species and distribution: Praearchirolithus is a monospecific genus with P. schultzei from the Upper Eocene of France, Paris Basin. Praearchirolithus schultzei (NOLF & LAPIERRE 1979) Figs. 851-853 syn. genus Soleidarum schultzei NOLF & LAPIERRE 1979 – NOLF & LAPIERRE 1979: pl. 6, figs. 21-23 (non figs. 24-25) Investigated otoliths: 13 otoliths (paratypes) from the Upper Eocene, Auversian of Ronquer- Distribution: Upper Eocene of France (Paris Basin) syn. Coryphillus CHABANAUD 1931 (type-species: Aseraggodes filiger), possible subgenus syn. Beaufortella CHABANAUD 1943 (type-species: Aseraggodes abnormis) syn. Synclidopus CHABANAUD 1943 (type-species: Solea macleayana), possible subgenus Diagnosis: Thin to moderately thickset compressed otoliths; ventral rim deeply and mostly regularly curving, dorsal rim more shallow, often irregularly curving, with massive, variable predorsal and less pronounced postdorsal angles, anterior rim blunt, posterior rim blunt, nearly vertically cut or broadly rounded, rarely concave. Index l:h less than 1.00. Otolith size up to 2.5 mm, diagnostic maturity probably reached at about 1.2 to 1.5 mm. Sulcus variable in width, moderately shallow, but sometimes deepened, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium usually wider than cauda and usually not much longer. Dorsal and ventral depressions moderately wide, somewhat deepened and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims more or less thickset. Schwarzhans: Pleuronectiformes 325 854a 854c 855a 855b 854b 858 857 856 Figs. 854-858: Aseraggodes kobensis (STEINDACHNER 1896) – 15 × Measurements: kobensis cyaneus klunzingeri macleayanus filiger l:h h:t ol:cl 0.95-1.00 2.9-3.3 1.2-1.4 0.85-0.95 3.7 0.9-1.0 1.05 3.8 0.9-1.05 1.05 2.4 2.2 0.95 3.3 1.0 oh:ch 1.0-1.35 1.0-1.15 0.95 1.35 0.95 con.i 2.5-3.8 4.0 3.2 2.2 2.6 Side dimorphism: Not apparent. Variability: Details of the outline and proportions of otolith and sulcus are all apt to some, usually minor, modifications. Discussion: Except for A. macleayanus otoliths of the genus Aseraggodes are characterized by the rather low index ol:cl and the relatively flat inner face with the rather wide circumsulcal depression. In A. filiger the anterior sulcal opening is reduced. The two somewhat aberrant species mentioned may be regarded as representatives of distinct subgenera or genera (Synclidopus and Coryphillus respectively). However, the genus Aseraggodes is very specious and otoliths so far are only known from relatively few species. More material of this interesting genus has to be investigated before any further conclusions can be Piscium Catalogus, Part Otolithi piscium, Vol. 2 drawn based on otoliths. Aseraggodes represents a somewhat separate lineage within the Pardachirus Group. Species and distribution: Aseraggodes is a specious genus widely distributed throughout the Indo-West Pacific. The following list of 22 species may not be complete: A. abnormis, A. bahamondi, A. beauforti, A. cyaneus, A. dubius, A. filiger, A. guttulatus, A. haackeanus, A. herrei, A. kaianus, A. klunzingeri, A. kobensis, A. macleayanus, A. melanostictus, A. microlepidotus, A. normani, A. ocellatus, A. persimilis, A. sinusarabici, A. smithi, A. texturatus, A. whittakeri. Of these species A. herrei from the Galapagos Islands is the only species outside the Indo-West Pacific. Aseraggodes kobensis (STEINDACHNER 1896) Figs. 854-858 Investigated otoliths: 6 otoliths (3 left and 3 right side) from off Kochi, Japan, ZMH Ot.11.6.1995.16 (leg. Sasaki). 326 859a 859c 861 860 859b Figs. 859-861: Aseraggodes cyaneus (ALCOCK 1890) – 15 × Discussion: A rather flat and roundish otolith with irregularly curving dorsal and posterior rims. Distribution: Coasts of Japan. Aseraggodes cyaneus (ALCOCK 1890) Figs. 859-861 syn. Solea umbratilis ALCOCK 1894 Investigated otoliths: 3 otoliths (1 left and 2 right side) from the Bay of Bengal, ZMH Ot. 11.6.1995.78 (leg. BMNH 1928.3.20.49-51) and BMNH 1928.3.20.49-51. Discussion: Very similar to A. kobensis, but somewhat more compressed and thin. Aseraggodes macleayanus (RAMSAY 1881) Fig. 862 Investigated otoliths: 1 otolith (left side) from Queensland, Australia, ZMH Ot.11.6.1995.10 (leg. ZMH 20110). Discussion: Otoliths of A. macleayanus are easily recognized by their outline (backward shift of the ventral rim and concave posterior rim), the deepened and widened ostium, the high index ol:cl and the very narrow ventral portion of the circumsulcal depression. In this respect they show quite some similarities with otoliths of the genus Pardachirus. Possibly A. macleayanus represents a distinct genus or subgenus of Aseraggodes, namely Synclidopus. Distribution: Australia, coasts of Queensland. Distribution: Persian Gulf to the Bay of Bengal. Aseraggodes filiger WEBER 1913 Fig. 865 Aseraggodes klunzingeri (WEBER 1908) Figs. 863-864 Investigated otoliths: 2 otoliths (left and right side) from New Guinea, ZMH Ot.11.6.1995.9 (leg. BMNH 1938.2.24.1-3) and BMNH 1938.2.24.1-3. Discussion: Similar to A. kobensis and A. cyaneus but less compressed and with a more regular outline. Investigated otoliths: 1 otolith (left side) from Singapore, BMNH 1934.9.6.2. Discussion: This otolith is characterized by its regular roundish outline and the anteriorly reduced sulcus. It may represent a distinct subgenus of Aseraggodes, namely Coryphillus. Distribution: Sea of Java to Malaysia. Distribution: Southern New Guinea ascending into the Lorentz and Meraukee rivers, northern Australia in Drysdale and Ord rivers. Schwarzhans: Pleuronectiformes 327 862a 862c 862b 862d 864 863a 865a 865b 863b 865c Fig. 862: Aseraggodes macleayanus (RAMSAY 1881) – 15 × Figs. 863-864: Aseraggodes klunzingeri (WEBER 1908) – 15 × Fig. 865: Aseraggodes filiger WEBER 1913 – 15 × †Pseudopardachirolithus n.gen. Type-species: Pseudopardachirolithus nolfi n.sp. Name: A combination of pseudo and the genus name Pardachirus; ending -lithus indicates it being an otolith based fossil genus. Diagnosis: A fossil, otolith based genus of the family Soleidae, subfamily Pardachirinae, Pardachirus Group with the following characters. The otoliths are small, up to 2.0 mm, compact and thickset with an index l:h well below 1.0. Ventral rim deeply curved, somewhat shifted backwards, dorsal rim high, somewhat irregularly curved, anterior rim blunt, posterior rim nearly vertically cut, slightly concave. Sulcus narrow to moderately wide, shallow, reaching close to the anterior rim of the otolith. Cauda much shorter than ostium. Circumsulcal depression dorsally widened, ventrally very narrow, resembling a ventral furrow, running close to the otolith rims. Inner face strongly convex, smooth; outer face flat, smooth. Rims rather sharp. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Measurements: †nolfi †sulci l:h 0.75-0.85 0.90-1.00 h:t 2.7 2.5 ol:cl oh:ch 1.65-2.4 0.95-1.05 1.85-2.0 0.8-0.9 con.i 1.6 1.6 Side dimorphism: Not apparent. Variability: Ornamentation of the outline and proportions of the otolith are apt to some minor modifications. Discussion: Otoliths of Pseudopardachirolithus are quite similar to those of Pardachirus. However, they are more thickset, with a more convex inner face and a more “primitive” character status of the circumsulcal depression and the sulcus. Apparently, both genera are closely related. The fossil Praearchirolithus is more roundish in outline and with a much less convex inner face, thus representing a still more primitive character state. Species and distribution: Two fossil species – P. nolfi from the Upper Eocene of France and P. sulci from the Upper Oligocene and Lower Miocene of France. 328 Pseudopardachirolithus nolfi n.sp. Figs. 866-869 syn. genus Soleidarum schultzei – NOLF & LAPIERRE 1979: pl. 6, figs. 24-25 (non figs. 21-23) Name: In honor of Dirk Nolf, renown otolith specialist from Brussels, Belgium. Holotype: Fig. 866, IRSNB P. Type locality: Ronquerolles, sheet Creil, x = 590275, y = 162300, Paris Basin, France. Age: Auversian, Upper Eocene. Paratypes: 6 otoliths (figs. 867-869), topo- and stratitypic, IRSNB P (all from the paratype sequence of genus Soleidarum schultzei). Diagnosis: Extremely high bodied, compact, small, thickset otoliths with an index l:h of 0.75 to 0.85. Ventral rim very deeply curving. Inner face strongly convex, smooth. Sulcus very narrow, shallow, ostium about two times as long as cauda. Description: Outline: Otoliths small (less than 1.5 mm), very high and compact. Ventral rim deeply curving, dorsal rim likewise, but somewhat irregularly, anterior rim blunt or broadly rounded, posterior rim vertically cut with faint concavity. Occasionally rims delicately crenulated. Otoliths very thickset. Inner face: Strongly convex and smooth. Sulcus long, narrow, shallow, with slightly supramedian position. Ostium about two times as long as cauda, similar in width. Separation of colliculi distinct. Circumsulcal depression close to the rims of the otolith, dorsally widened, ventrally reduced to a narrow line. Other views: Rims rather sharp. Outer face smooth, nearly flat. the Upper Oligocene and Lower Miocene of France is somewhat less high bodied with the backward shifted ventral rim and a wider sulcus. Both species likely represent part of a fossil lineage. Distribution: Upper Eocene of France (Paris Basin). Pseudopardachirolithus sulci (STEURBAUT 1984) Figs. 870-871 syn. genus aff. Paraplagusia sp. – STEURBAUT 1979: pl. 11, fig. 18 syn. Solea sulci STEURBAUT 1984 – STEURBAUT 1984: pl. 35, figs. 24-26 Investigated otoliths: 2 otoliths (left and right side), paratypes (IRSNB P 4265-4266) from the Burdigalian, Lower Miocene of Pont-Pourquey, Aquitaine Basin, France. Discussion: Similar to P. nolfi (see respective entry). Distribution: Upper Oligocene and Lower Miocene of France (Aquitaine Basin) Pardachirus GÜNTHER 1862 Type-species: Achirus marmoratus (LACEPEDE 1802) syn. Liachirus GÜNTHER 1862 (type-species: L. nitidus, syn. P. melanospilos) syn. Normanetta WHITLEY 1931 (type-species: Achirus poropterus) Side dimorphism: Not apparent. Ontogeny and variability: Proportions of the otolith and details of the outline may vary slightly. Sometimes the otolith margins are delicately ornamented. This seems to occur in the smallest specimens only and could be an ontogenetic effect. Discussion: Holotype and paratypes of this species originally have been described in the type sequence of genus Soleidarum schultzei (see Praearchirolithus schultzei). However, they are easily distinguished by the characters given in the diagnosis. The geologically younger P. sulci from Diagnosis: Thin to moderately thickset compressed otoliths; ventral rim deeply and regularly curving, somewhat shifted backwards, dorsal rim more shallow, often irregularly curving, with massive, variable predorsal and less pronounced postdorsal angle, anterior rim broadly rounded, posterior rim blunt to vertically cut, sometimes with faint concavity. Index l:h 0.90 to 1.05. Otolith size up to 3.0 mm, diagnostic maturity probably reached at about 1.5 mm. Sulcus rather narrow, shallow, rarely somewhat deepened, position slightly supramedian, anteriorly reaching close to the anterior rim of Schwarzhans: Pleuronectiformes 329 866c 868 866a 867 869 866b 870b 871 870c 870a Figs. 866-869: Pseudopardachirolithus nolfi n.sp. – 25 × Figs. 870-871: Pseudopardachirolithus sulci (STEURBAUT 1984) – 25 × the otolith. Ostium usually narrower than cauda, much longer. Colliculi nearly fused. Dorsal and ventral depressions very narrow like a furrow, well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims more or less sharp. Measurements: hedleyi marmoratus pavoninus melanospilos l:h 1.00 0.95 0.90 1.05 h:t 3.5 2.7 3.4 3.1 ol:cl 1.75 1.80 1.35 2.40 oh:ch 0.85 0.70 0.90 1.05 con.i 2.4 1.8 2.5 2.6 Side dimorphism: Not apparent, according to a sequence of otoliths of P. pavoninus figured in CHAINE (1936). Variability: According to figures by CHAINE (1936) limited to variations in the proportions of the otolith and details of the outline. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Otoliths of the genus Pardachirus show a number of similarities with genera of the Heteromycteris Group (see respective entry) and also resemble Cynoglossid otoliths, except for that those show completely fused colliculi and the peculiar “hammer” shaped sulcus. Pardachirus and possibly also the related genus Parachirus (of which otoliths are not known) represent the most apomorphic genus in the Pardachirus Group. The monospecific genus Liachirus (L. melanospilos) is being placed in synonymy with Pardachirus based on the very close resemblance of its respective otoliths. Species and distribution: Pardachirus contains 6 nominal species from the Indo-West Pacific – P. hedleyi, P. marmoratus, P. melanospilos, P. morrowi, P. pavoninus and P. poropterus. 330 Pardachirus hedleyi OGILBY 1916 Fig. 872 Daresalam (?), ZMH Ot.11.6.1995.13 (leg. ZMH 20118). Investigated otoliths: 1 otolith (left side) from New South Wales, Australia. BMNH 1925.9.21.4. Remarks: The label of the specimen from the ZMH collection, from which the otolith was extracted, is either faulty since it indicates as location Daresalam in Tanzania or it represents a different species. According to the geographical distribution pattern, this could then possibly be P. morrowi. Discussion: P. hedleyi is recognized by its somewhat deepened cauda and the still rather wide circumsulcal depression. Distribution: Coasts of Queensland and New South Wales, Australia. Pardachirus marmoratus (LACEPEDE 1802) Fig. 873 Investigated otoliths: 1 otolith (left side) from East Africa, ZMH Ot.11.6.1995.11 (leg. ZMH 20121). Discussion: Very similar to P. pavoninus but more rounded in outline, with a more widened cauda and a more strongly convex inner face. Distribution: Persian Gulf to Red Sea and East Africa south to Mozambique and Madagascar. Pardachirus pavoninus (LACEPEDE 1802) Fig. 875 Discussion: Characterized by a somewhat pointed anterior rim and an index l:h of slightly over 1.0. Distribution: Coasts of India, Indonesia and China. Parachirus MATSUBARA & OCHIAI 1963 Type-species: Parachirus xenicus MATSUBARA & OCHIAI 1963 Remarks: Otoliths of Parachirus have not been available for investigation. Parachirus is apparently closely related to Pardachirus. Species and distribution: Parachirus is a monospecific genus with P. xenicus known from Japan through the Indo-West Pacific to South Africa. syn. Achirus maculatus KUHL & v.HASSELT 1845 7.8.8 Heteromycteris Group Investigated otoliths: 1 otolith (left side) from Singapore, ZMH Ot.11.6.1995.12 (leg. ZMH 20123). Genera: The Heteromycteris Group (or Heteromycterinae of CHABANAUD, 1939) as understood here contain three genera – Heteromycteris, Rendahlia and Peltorhamphus. Since NORMAN (1934) Peltorhamphus has been placed in the Pleuronectidae in the subfamily Rhombosoleinae, although he noted that some genera bear some superficial resemblance with Soleidae. According to otolith analysis Rhombosoleinae are regarded as a polyphyletic combine (see entries to chapters 5.3.2., the Ammotretis Group, Pleuronectidae and the Samaris, Pelotretis and Rhombosolea Groups). However, NORMAN was right in regarding similarities of his Rhombosoleinae with Soleidae as purely superficial, that is except for Peltorhamphus. Otolith analysis clearly characterizes Peltorhamphus as a Soleidae, probably close to Heteromycteris. This conclusion, however, needs to be verified by other ichthyological investigations. Discussion: Similar to P. marmoratus but more high bodied and with conspicuous predorsal projection; also cauda less widened. Distribution: Andaman Islands to Japan and northern Australia. Pardachirus aff. melanospilos (BLEEKER 1854) Fig. 874 syn. Liachirus nitidus GÜNTHER 1862 Investigated otoliths: 1 otolith (left side) from Schwarzhans: Pleuronectiformes 331 873a 872a 873c 872c 873b 872b 874a 875a 875c 874b 874c 875b Fig. 872: Pardachirus hedleyi OGILBY 1916 – 15 × Fig. 873: Pardachirus marmoratus (LACEPEDE 1802) – 15 × Fig. 874: Pardachirus aff. melanospilus (BLEEKER 1854) – 15 × Fig. 875: Pardachirus pavoninus (LACEPEDE 1802) – 15 × Fishes of the Heteromycteris Group are distributed from the West African coast through the Indo-West Pacific. Peltorhamphus is entirely endemic to the waters around New Zealand. Definition and relationship: Otoliths of the Hetromycteris Group share a number of apomorphic characters with those of the Pardachirus Group, such as the shallow sulcus with the short cauda, the smooth convex inner face, the narrow circumsulcal depression and the general outline of the otolith. Differing from otoliths of the Pardachirus Group is the position of the circumsulcal depression at some distance from the rims of the otoPiscium Catalogus, Part Otolithi piscium, Vol. 2 liths and the tendency to enlarge the cauda. The latter character, the widened cauda, has further developed in Cynoglossidae to the characteristic “hammer” shaped sulcus with completely fused colliculi. In fact the overall pattern of Cynoglossid otoliths show good resemblance to those of the Heteromycteris and Pardachirus Groups. Fishes of the Heteromycteris Group too resemble cynoglossids in the loss of the pectoral fins and the incipiently hooked mouth. I therefore postulate that the Cynoglossidae have derived from near the Pardachirinae and there possibly the Heteromycteris Group (see also entry to Cynoglossidae). 332 Heteromycteris KAUP 1858 Type-species: Heteromycteris capensis KAUP 1858 syn. Amate JORDAN & STARKS 1906 (type-species: Achirus japonicus) syn. Monodichthys CHABANAUD 1925 (typespecies: M. proboscideus) Diagnosis: Thin to moderately thickset, rather elongate otoliths; ventral rim not very deeply and mostly regularly curving, somewhat shifted backwards, dorsal rim more shallow, often irregularly curving, with massive, variable predorsal and less pronounced postdorsal angle, anterior rim rounded, posterior rim blunt, rounded. Index l:h 1.20 to 1.40. Otolith size up to 3.5 mm, diagnostic maturity probably reached at about 1.2 mm. Sulcus rather narrow, moderately shallow to shallow, position median to slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium narrower than cauda and much longer. Dorsal and ventral depressions rather narrow, somewhat deepened, close to the sulcus and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims sharp to moderately thickset. l:h h:t 1.25-1.40 1.9-2.2 1.35-1.40 2.2 1.20 3.2 Heteromycteris japonicus (TEMMINCK & SCHLEGEL 1846) Figs. 876-877 Investigated otoliths: 2 otoliths (left side) from the Inland Sea of Japan, ZMH Ot.12.6.1995.1 (leg. BMNH 1905.6.6.223-7) and BMNH 1905.6.6.223-7. Discussion: Rather thickset otoliths with a slightly deepened sulcus. Distribution: Coasts of China and Japan. Heteromycteris oculus (ALCOCK 1889) Figs. 878-879 Investigated otoliths: 2 otoliths (left side) from the Ganjam coast, India, ZMH Ot.12.6.1995.2 (leg. BMNH 1928.3.20.52-56) and BMNH 1928.3.20.5256. Discussion: Otoliths of H. oculus are characterized by their rather massive predorsal projection. Measurements: japonicus oculus capensis lus from the Indian subcontinent, H. cheni from China and H. japonicus and H. matsubarai from Japan. H. hartzfeldi is being placed in the genus Rendahlia (see respective entry). ol:cl 2.3-2.8 2.0-2.5 2.8 oh:ch 0.6-0.75 0.7-1.0 0.7 con.i 2.2-2.6 2.5 2.8 Side dimorphism: Not data. Ontogeny and variability: A rather large otolith of H. japonicus shows a more gently curving ovale outline and is also more thickset than smaller ones. Variability apparently is very limited in this genus, restricted mainly to details of the dorsal rim and variations in the index oh:ch. Discussion: Otoliths of Heteromycteris are very similar to those of the related genus Rendahlia. However, the latter are more compressed and the shape of the sulcus has further advanced to resemble Cynoglossidae. Species and distribution: Heteromycteris contains 6 nominally valid species – H. proboscideus from West Africa, H. capensis from South Africa, H. ocu- Distribution: Coasts of India. Heteromycteris capensis KAUP 1858 Fig. 880 Investigated otoliths: 1 otolith (left side) from False Bay, South Africa, BMNH 1930.5.6.43. Discussion: Otolith rather thin and more compressed than those of the two other species. Distribution: Coasts of South Africa. Rendahlia CHABANAUD 1930 Type-species: Achirus jaubertensis RENDAHL 1923 Diagnosis: Thin, compressed otoliths; ventral rim deeply and mostly regularly curving, some- Schwarzhans: Pleuronectiformes 333 877c 877a 876a 876b 878c 877b 879 878a 878b 880a 880b Figs. 876-877: Heteromycteris japonicus (TEMMINCK & SCHLEGEL 1846) – 15 × Figs. 878-879: Heteromycteris oculus (ALCOCK 1889) – 15 × Fig. 880: Heteromycteris capensis KAUP 1858 – 15 × what shifted backwards, dorsal rim more shallow, often irregularly curving, with weak predorsal and pointed postdorsal angle, anterior rim rounded, sometimes pointed, posterior rim blunt, incipiently concave. Index l:h 1.05 to 1.15. Otolith size may be up to 3.0 mm, diagnostic maturity probably reached at about 1.0 mm. Sulcus rather narrow, moderately shallow to shallow, position slightly supramedian, anteriorly reaching close to the anterior rim of the otolith. Ostium narrower than cauda and longer. Dorsal and ventral depressions rather narrow, somewhat deepened, close to the sulcus and well connected around the cauda to form a circumsulcal depression. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Inner face markedly convex, smooth; outer face almost flat, smooth. Rims sharp. Measurements: hartzfeldi jaubertensis l:h 1.05 1.10-1.15 h:t 2.9 3.1 ol:cl nm 1.8-2.0 oh:ch 0.6 0.6 con.i 2.5 1.5 Side dimorphism: The single right hand otolith of R. jaubertensis shows a somewhat smaller, slightly deepened sulcus. Discussion: Otoliths of Rendahlia are very similar to Heteromycteris. They differ in being more compressed and showing a more widened cauda (index oh:ch) thus more closely resembling Cynoglossid otoliths. 334 Species and distribution: Originally described as a monospecific genus I have also placed R. hartzfeldi in this genus, purely based on its otolith morphology. Rendahlia hartzfeldi (BLEEKER 1853) Fig. 881 syn. Heteromycteris normani CHABANAUD 1935 Investigated otoliths: 1 otolith (left side) from Singapore, BMNH 1934.9.6.4. Discussion: Otoliths of R. hartzfeldi are readily recognized by the pointed postdorsal angle and the completely fused colliculi. In this respect they almost perfectly resemble Cynoglossid otoliths, differing mainly in the circumsulcal depression located close to the sulcus. Distribution: Gulf of Bengal, Malaysia, Indonesia and New Guinea. Rendahlia jaubertensis (RENDAHL 1923) Figs. 882-883 Investigated otoliths: 2 otoliths (left and right side) from Lord Byron Island, Timor Sea off Derby, NW-Australia, 16°10’S/123°28’E, ZMH Ot.12.6.1995.3-4 (leg. WAM P 30319-023). Discussion: Similar to R. hartzfeldi, but with pointed anterior tip and separated colliculi. Distribution: Northwest Australia. Peltorhamphus GÜNTHER 1862 Type-species: Peltorhamphus novaezeelandiae GÜNTHER 1862 Diagnosis: Thin to moderately thickset, compressed otoliths; ventral rim deeply and regularly curving, shifted backwards, dorsal rim more shallow, often irregularly curving, with massive, variable pre- to middorsal projection and rounded postdorsal angle, anterior rim rounded, posterior rim blunt, rounded to vertically cut. Index l:h 0.75 to 1.10. Otolith size up to 4.5 mm, diag- nostic maturity probably reached at about 1.5 to 2.0 mm. Sulcus moderately wide, moderately shallow to shallow, cauda sometimes deepened, position median to slightly supramedian, anteriorly reaching close to the anterior rim of the otolith or opening to it (pseudoostial opening). Ostium narrower than cauda and much longer. Separation of colliculi variable, sometimes quite indistinct. Dorsal and ventral depressions moderately wide, slightly deepened, close to the sulcus and well connected around the cauda to form a circumsulcal depression. Inner face markedly convex, smooth; outer face almost flat, smooth. Rims sharp. Measurements: novaezeelandiae †flexodorsalis latus tenuis †fordycei l:h 1.00-1.10 1.05-1.10 1.10 0.90-1.00 0.75-0.80 h:t 4.2 2.7 3.3 3.1 3.5 ol:cl (1.6-2.2) 2.1-2.4 1.8 2.1-2.7 1.6-1.9 oh:ch 0.85-0.9 0.65-0.9 1.0 0.8-1.0 0.95-1.0 con.i 2.1-2.5 2.3 2.6 1.8-2.0 2.2 Side dimorphism: Not apparent. Sometimes it seems that otoliths of the right side are slightly more compressed than those of the left side. Ontogeny and variability: Otoliths of 2 mm of size and smaller are usually more rounded in outline than larger ones. Variability is moderate, restricted to details of the outline and proportions of otolith and sulcus. Also the degree of the ostial opening is apt to some modifications. Discussion: Peltorhamphus is generally regarded as a Pleuronectidae, subfamily Rhombosoleinae (NORMAN, 1934). Otoliths, in my opinion, clearly demonstrate this genus to represent a Soleidae, probably close to Heteromycteris. This hypothesis, however, needs to be verified by other ichthyological investigations. Species and distribution: Peltorhamphus is endemic to the sea around New Zealand. It contains 3 recent species – P. novaezeelandiae, P. latus and P. tenuis – plus 2 fossil species – P. fordycei from the Miocene and P. flexodorsalis from the Pliocene. Also P. tenuis is known as fossil from the Pliocene of New Zealand. Schwarzhans: Pleuronectiformes 335 881c 881a 883 882a 881b 882b Fig. 881: Rendahlia hartzfeldi (BLEEKER 1853) – 15 × Figs. 882-883: Rendahlia jaubertensis (RENDAHL 1923) – 25 × Peltorhamphus novaezeelandiae GÜNTHER 1862 Figs. 884-886 Investigated otoliths: 5 otoliths, 4 (left and right side, figs. 884-886), AIM 2760 (coll. Grenfell) and 1 (right side) from off Wellington, New Zealand, BMNH 73.12.13.14-15. Discussion: Otoliths of P. novaezeelandiae are rather compressed with a massive middorsal projection. The differ from the related fossil P. flexodorsalis in the almost completely fused colliculi. Also in P. flexodorsalis the middorsal projection is still more massively developed. Distribution: New Zealand. Peltorhamphus flexodorsalis n.sp. Figs. 888-894 Name: flexus (lat.) = bent and dorsalis, referring to the very strongly developed middorsal projection. Holotype: Fig. 888, BSP 1984 X 117. Type locality: Martinborough, New Zealand northern Island. Age: Wanganuian, Pliocene. Paratypes: 6 otoliths (figs. 889-894), topo- and stratitypic, BSP 1984 X 118-123. Diagnosis: Compressed, massive otoliths with an extremely strongly developed middorsal projection. Postdorsal portion often concave. Ostium and cauda clearly separated, cauda somewhat deepened, ostium anteriorly open (pseudoostial opening). Piscium Catalogus, Part Otolithi piscium, Vol. 2 Description: Outline: Otoliths compressed with a moderately deeply curving ventral rim, shifted far backwards. Dorsal rim with extremely strongly developed middorsal projection, often concave behind. Anterior rim rounded, sometimes with pseudo-excisura, posterior rim blunt, nearly vertically cut. Otolith compact, moderately thickset. Inner face: Convex and rather smooth. Sulcus long, moderately wide, with median position and slightly deepened, especially the cauda. Ostium at least two times as long as cauda, slightly narrower, anteriorly open (pseudoostial opening). Colliculi well separated. Circumsulcal depression moderately wide, rather shallow, close to the sulcus, well connected around the caudal tip of the sulcus. Other views: Outer face nearly flat, rather smooth. Rims mostly sharp. Side dimorphism: Otoliths of the right side seem to be slightly more compressed than those of the left side. Ontogeny and variability: Otoliths of 2 mm of size and smaller are usually more rounded in outline than larger ones. Variability is moderate, restricted to details of the outline and proportions of otolith and sulcus. Also the degree of the ostial opening is apt to some modifications. Discussion: P. flexodorsalis is very close to the recent P. novaezeelandiae and may very well represent the direct ancestor. It differs in the more strongly developed middorsal projection and the clear separation of the colliculi. 336 885a 884a 884b 884c 885b 887c 887a 886 887b Figs. 884-886: Peltorhamphus novaezeelandiae GÜNTHER 1862 – 15 × Fig. 887: Peltorhamphus latus JAMES 1972 – 15 × Peltorhamphus latus JAMES 1972 Fig. 887 Peltorhamphus tenuis JAMES 1972 Figs. 895-899 Investigated otoliths: 1 otolith (left side) (paratype) from the Tasman Bay, New Zealand, 41°0’S/ 173°7’E, BMNH 1970.12.15.3-5. Investigated otoliths: 1 otolith (left side, fig. 895) (paratype) from Pegasus Bay, New Zealand, 43°27’S/172°7’E, BMNH 1970.12.15.10-11 and 5 fossil specimens (figs. 896-899) from the Pliocene, Wanganuian of Martinborough, New Zealand north island. Discussion: Similar to P. novaezeelandiae but with very shallow middorsal portion and with clearly separated colliculi. Also the sulcus is rather wide. Distribution: New Zealand. Schwarzhans: Pleuronectiformes 337 889 888a 888c 888b 890 891 892 894 893 Figs. 888-894: Peltorhamphus flexodorsalis n.sp. – 15 × Discussion: Otoliths of P. tenuis are more compressed than those of the other two recent species and show a rather gently curving dorsal rim. Distribution: New Zealand, also known as fossil from the Pliocene of the same area. Peltorhamphus fordycei (SCHWARZHANS 1980) Figs. 900-902 syn. Achirus fordycei SCHWARZHANS 1980 – SCHWARZHANS 1980: figs. 585-588 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 5 otoliths, including holotype (fig. 900) and paratypes (figs. 901-902) from the Double Corner Shellbed Formation, Lillburnian/Waiauan, Middle Miocene of the Waipara river, sheet S68-137/074, Canterbury, New Zealand south island, NZGS. Discussion: Otoliths of P. fordycei are readily recognized by their extremely low index l:h. Distribution: Middle Miocene of New Zealand. 338 895b 896b 896a 895c 895a 898 897 899 901 902 900c 900a 900b Figs. 895-899: Peltorhamphus tenuis JAMES 1972 – 15 × Figs. 900-902: Peltorhamphus fordycei (SCHWARZHANS 1980) – 15 × 7.9 Cynoglossidae Genera: The family Cynoglossidae contains 2 large genera – Cynoglossus and Symphurus. Each of the two genera contains more than 50 species making them the most speciouss genera of the Pleuronectiformes. A third genus usually recognized in ichthyological literature – Paraplagusia (with only few species) – is here regarded as a subgenus of Cynoglossus (for reasoning see below and introduction to Cynoglossus). The otoliths of the various species of both genera show a distinct clustering. These clusters are presented here in subgeneric ranking using generic names from the synonymy lists of the respective genera (see respective entries). It is envisaged that these clusters could be given generic ranking if supported by other ichthyological analyses. Definition and relationship: The Cynoglossidae are the amalgamation of all left eyed Soleoidei (and the Soleidae of the right eyed Soleoidei). In some literature they are subdivided into two subfamilies – the Cynoglossinae and the Symphurinae. Schwarzhans: Pleuronectiformes 339 Apparently, Cynoglossidae form a morphologically well defined and dense cluster. Their otoliths are immediately recognized by the “hammer” shaped sulcus. The sulcus is shallow, not or not distinctly opening anteriorly and filled with a uniform colliculum. Anteriorly (representing the ostium) it is narrow, posteriorly (representing the cauda) it is extremely widened dorsally and ventrally with a nearly vertically cut termination resulting in the typical “hammer” shaped outline. Else, the inner face typically is convex and smooth, with a narrow furrow-like circumsulcal depression close to the rims of the otolith. In outline, the otoliths are often very high bodied, commonly with a massive predorsal projection and a far backwardly shifted postventral corner. The otolith pattern of the Cynoglossidae resembles that of certain genera of the Pardachirinae (Soleidae) even to the point that the “hammer” shaped sulcus is foreshadowed in those genera. Such initial feature is found in the genera of the Heteromycteris Group of the Pardachirinae like in the genus Rendahlia (see respective entries). The fishes of the Heteromycteris Group too resemble cynoglossids in the loss of the pectoral fins and the incipiently hooked mouth. From these observations it may be concluded that the Cynoglossidae have derived from near the Pardachirinae and thus represent a paraphyletic unit. The members of the Cynoglossidae have recently been subject to a phylogenetical study by CHAPLEAU (1987). He regarded the genus Symphurus as the most plesiomorphic in the family forming the sister group to Cynoglossus and Paraplagusia, the latter representing the most apomorphic one. Similar views were expressed in MENON’s review of the genus Cynoglossus in 1977. Otoliths, however, point to a completely different phylogenetic alignment. Those of the genus Symphurus exhibit a number of additional and highly specialized characters (for details see entry to genus) which can not possibly be interpreted as plesiomorphic in comparison with the genus Cynoglossus. Therefore, it may be questioned whether the seemingly primitive characters observed in fishes of the genus Symphurus may not possible represent a reduction rather than a plesiomorphic character state. In the fossil record, cynoglossid otoliths are rare, but both genera are known since Lower Miocene times (not identifiable to the species in the case of Symphurus). Typical representatives of Piscium Catalogus, Part Otolithi piscium, Vol. 2 the genus Cynoglossus from the Miocene, however, document that the genus is probably older than assumed by MENON (1977). Also its occurrence in European sediments contradicts his hypothesis that the genus Cynoglossus had developed in the Indian Ocean and as lately as Pliocene, after the Tethyan waterways had been destructed. The wider present day geographical distribution of the genus Symphurus is irrelevant in this respect since it is a genus mostly adapted to deeper water. Plate tectonic developments and paleogeographic situations should be used much more carefully to explain recent biogeographic distribution patterns or phylogenetic assumptions, especially in the (seeming) absence of fossil data. Distribution: Cynoglossidae are widely distributed throughout the tropical and subtropical seas. The genus Cynoglossus chiefly occurs in the shallow water of the Indo-West Pacific and with few species in the East Atlantic. Fishes of the genus Symphurus are mostly adapted to deeper water on the continental shelfs and slopes in all tropical and subtropical oceans. 7.9.1 Cynoglossus Group Genera: One genus – Cynoglossus. Paraplagusia is regarded as a subgenus of Cynoglossus (see entry to genus). Definition and relationship: Otoliths of the genus Cynoglossus show the typically shallow “hammer” shaped sulcus with fused colliculi and the high bodied outline often with a massive predorsal projection and a backwardly shifted postventral corner. Typically, the inner face is convex and smooth, with a narrow circumsulcal depression running close to the otolith rims. A similar pattern is foreshadowed in the Pardachirinae (Heteromycteris Group) from near which Cynoglossidae are supposed to have derived. Otoliths of the second cynoglossid group, the Symphurus Group, show further specializations such as the anteriorly reduced sulcus, a very special development of the postdorsal and the postventral portions of the circumsulcal depression (bilobate) and the backwardly shifted dorsal rim. It is therefore assumed that Symphurus originated from near certain species groups within the genus Cynoglossus, where similar trends can be observed. 340 Cynoglossus HAMILTON-BUCHANAN 1822 Type-species: Cynoglossus lingua HAMILTONBUCHANAN 1822 syn. Cantoria KAUP 1858 (type-species: Plagusia potous, syn. C. arel) syn. Arelia KAUP 1858 (type-species: C. arel) syn. Icania KAUP 1858 (type-species: C. cynoglossus) – subgenus syn. Trulla KAUP 1858 (type-species: Trulla cantori, syn. C. borneensis) – subgenus syn. Paraplagusia BLEEKER 1865 (type-species: Pleuronectes bilineatus) – subgenus syn. Rhinoplagusia BLEEKER 1875 (type-species: Plagusia japonica) syn. Usinostia JORDAN & SNYDER 1900 (typespecies: Plagusia japonica) syn. Areliscus JORDAN & SNYDER 1900 (typespecies: C. joyneri) syn. Cynoglossoides VON BONDE 1922 (type-species: C. attenuatus) syn. Dollfusichthys CHABANAUD 1931 (typespecies: D. sinusarabici) syn. Dexiourius CHABANAUD 1947 (type-species: C. semilaevis) – subgenus syn. Cynoglossoides [not VON BONDE 1922] SMITH 1949 (type-species: C. ecaudatus) Diagnosis: Thin to moderately thickset, ovale to high bodied otoliths; ventral rim deeply curving, anteriorly inclined, posteriorly with massive corner towards the posterior rim, dorsal rim more shallow with postdorsal angle and usually massive predorsal projection, anterior rim broadly rounded, posterior rim high, oblique or vertically cut, with or without concavity, or broadly rounded. Maximal otolith size variable, up to and more than 5 mm in large species and 1.5 to 2 mm in dwarfed species. Sulcus usually shallow, occasionally somewhat deepened, with fused colliculi, typical “hammer” shaped outline, not or indistinctly opening anteriorly. Circumsulcal depression well developed but very narrow, often furrow like, sometimes postdorsally somewhat widened, running close to the otolith rims. Inner face markedly to strongly convex, usually rather smooth; outer face flat to markedly concave, rarely convex, usually smooth. Rims usually sharp, occasionally more thickset, not or only faintly ornamented. Subgeneric definitions: The various species of the genus Cynoglossus can be subdivided in species clusters by means of otolith analysis to which subgeneric ranking and naming from the synonymy list can provisionally be applied (see discussion lateron for more details). Otoliths of the subgenus Trulla show a very convex and rather smooth inner face. The predorsal projection is strongly developed. Otoliths of the subgenus Dexiourius are similar to Trulla, but usually with a less pronounced predorsal projection and a not so much widened cauda, often with a rounded termination. – Both subgenera are supposed to represent rather plesiomorphic otolith patterns. Otoliths of the subgenus Paraplagusia again have a very convex and very smooth inner face. The sulcus is completely flat and a predorsal projection is completely missing. The subgenus Cynoglossus contains a number of dwarfed species. Otoliths have a rather flat inner face and the ostium is anteriorly narrowed, often pointed. A predorsal projection is developed. The circumsulcal depression has developed some kind of secondary funnel-shaped connection towards the extended dorsal and ventral tips of the cauda. This character is similarly developed as in the genus Symphurus. The subgenus Icania again contains numerous dwarfed species. Otoliths resemble those of the subgenus Cynoglossus in the rather flat inner face and the moderate predorsal projection but lack the anterior narrowing of the ostium and the peculiar development of the circumsulcal depression. Instead a tendency is observed to smoothen the outline of the sulcus. This has developed furthest in C. carpentari where the sulcus secondarily has become ovale again and is also considerably deepened. Measurements: l:h subgenus Trulla canariensis †obliqueventralis dubius borneensis senegalensis quadrilineatus lida h:t 0.95-1.00 3.3 0.80-0.85 4.3 1.20-1.30 4.9 1.05-1.15 4.0 1.10 3.3 1.10-1.20 2.6-3.0 1.25 3.0 subgenus Dexiourius kapuasensis 1.05 heterolepis 1.30 feldmanni 0.95 semilaevis 1.10 2.8 2.4 3.4 3.8 l:ol ch:oh con.i 1.5-1.6 1.7 1.7-1.8 1.6-1.8 1.7 1.5 1.5 1.9 2.4-2.6 1.7-1.9 1.9-2.1 2.0 1.5-1.6 2.0 3.0 2.6 3.7 3.0 2.9 2.6 2.6 1.6 2.0 1.5 1.9 2.6 1.7 2.1 2.0 2.1 2.8 2.5 2.6 Schwarzhans: Pleuronectiformes 341 gracilis abbreviatus trigrammus 1.00 1.00 1.05 subgenus Paraplagusia dispar 1.05 japonicus 1.05-1.10 bilineatus 1.15 blochi 1.40 unicolor 1.15 4.2 5.0 3.3 1.8 1.7-1.9 1.7 2.3 2.0 2.1 3.2 2.3 3.4 4.4 3.4 3.7 3.5 3.2 1.5-1.6 1.8-1.9 2.5 1.6-1.71.5-1.8 1.7-1.9 1.6 2.2 1.9 1.8 1.7 2.3 1.8 1.8 1.9 subgenus Cynoglossus arel 1.05-1.10 3.7 robustus 1.10-1.15 4.1 lingua 1.20-1.30 3.0 joyneri 1.25-1.35 2.8-3.0 itinus 0.85-0.90 3.3 kopsi 1.00-1.05 3.8 interruptus 0.95 nm sealarki 1.00 3.6 zanzibarensis 1.15 3.1 1.6-1.8 1.7-1.9 1.6-1.7 1.6-1.8 1.5-1.7 1.8-1.9 2.2 1.9-2.1 1.9 3.5-4.1 3.3-3.6 3.1-4.4 1.7-2.2 2.6-3.4 6.5-7.0 3.5 3.6-3.9 3.0-4.5 subgenus Icania broadhursti 0.90 3.5 maculipinnis 0.90 3.2 gilchristi 0.90 3.4 puncticeps 0.85-0.90 4.1 †leuchsi 0.85-0.95 4.0 cynoglossus 1.15 3.0 semifasciatus 1.10 2.8 monopus 1.20 3.2 carpentari A 1.30-1.50 2.4-2.6 carpentari B 1.20 3.2 1.4-1.6 1.6-1.7 1.8 1.8-1.9 1.6-1.8 1.8 1.9 2.1 1.8-2.4 1.9-2.3 2.4-2.9 3.4 2.7-3.0 2.6 2.4 2.0 2.2-2.4 1.9 2.3-2.6 nm 1.7 3.7 2.4 3.0 1.3 3.0 nm about 7 nm about 10 6.0 4.5 5.5 4.5 1.9 2.3 nm 2.6 3.7 Side dimorphism: Usually not apparent. Sometimes a very faint degree of side dimorphism is seen in details of the outline. Ontogeny and variability: Smaller otoliths are usually more gently rounded and thus less characteristic than larger ones. All in all the degree of ontogenetical changes is rather small and in most instances juvenile otoliths can be attributed without much difficulties. However, in the presence of dwarfed species in the same area differentiation of otoliths from adult dwarfed species from small otoliths of large species could become difficult. Variability in most species is at low or moderate level mainly concerning details of the outline and minor variations in sulcus proportions. Discussion: The various species of the genus Cynoglossus have been comprehensively revised by MENON (1977). He defined six major species groups, some of them including subgroups (or complexes, as he termed them). He did not officially name them as subgenera, because he felt Cynoglossus to represent a very dense cluster in itself with a mosaic morphology distribution. Like in most ichthyological literature Paraplagusia was then excluded as a separate genus, which MENON reviewed in 1979. Piscium Catalogus, Part Otolithi piscium, Vol. 2 MENON (1977, 1979) stated that “Paraplagusia can be distinguished from Cynoglossus mainly by its possession of a series of fringes an the lips on the ocular side. In all other features, including the osteology, Paraplagusia is very similar to Cynoglossus”. Otoliths support this close relationship. In fact, otolith morphology in the genus Cynoglossus is more diverse than differences of some of its species to the four species usually placed in Paraplagusia. It seems that separation of Paraplagusia from Cynoglossus is mainly based on a single highly obvious and autapomorphic character. In my opinion this is a typical case of paraphyly. Either the various species groups observed in Cynoglossus have to be raised to genus level or else Paraplagusia must be regarded as a subgenus of Cynoglossus in order to arrive at a sound phylogenetic classification. I have here chosen the second solution and have included Paraplagusia in Cynoglossus. MENON’s groups and complexes have been divided based on a number of meristic characters such as presence or absence of lateral lines on the blind side, number of rays in the caudal fin, size of eyes, width of interorbital space, shape of snout and others (f.i. dwarfing of species). I have investigated otoliths of 35 species of the 54 included in this genus (including 4 species traditionally being placed in Paraplagusia). This covers all of MENON’s species groups and complexes except for the monospecific C. macrophthalmus complex and the C. ecaudatus complex. (An otolith extracted from C. ecaudatus was so brittle due to the effects of formalin that it fell apart when touched by the tweezers. However, it seemed to be a compact, thick otolith probably not unlike the one from C. sealarki). His grouping in most instances compares very well with the grouping according to otolith patterns. The species placed here in the subgenus Trulla quite well corresponds to MENON’s canariensis group. I have, however, excluded C. dispar and placed it in the subgenus Paraplagusia chiefly because of its otolith morphology, although the presence of a lateral line on the blind side was used as a prime character by MENON to define this group. On the other hand C. lida was tentatively included from MENON’s cynoglossus group. Otoliths of C. attennatus recently figured by SMALE et al. (1995) suggest that this species may also belong to the subgenus Trulla. – MENON regarded this group as the most primitive in the genus because of the presence of lateral 342 lines on the blind side. Otoliths suggest this too since the cauda is not as much widened as compared to the ostium and compared to the situation in most other groups (index ch:oh mostly below 2). The species placed in the subgenus Dexiourius represent MENON’s heterolepis group. However, unlike MENON I do not regard it as closely related to the carpentari group (subgenus Icania), but instead as a still rather primitive group close to Trulla. In particular the posteriorly rounded cauda is an indication of the primitive status of this subgenus. The subgenus Paraplagusia corresponds to the genus Paraplagusia of MENON (1977, 1979), only that C. dispar has tentatively been included as well (see above). Despite the obvious specialization of the lips (see above) characterizing the fishes of this subgenus, otoliths seem to indicate that this too is still a rather plesiomorphic subgenus (low index ch:oh). However, the very strongly convex inner face found in the otoliths of this subgenus and the shallow predorsal rim must be regarded as apomorphic developments. The species placed in the subgenus Cynoglossus comprises the kopsi (to the largest part) and arel groups of MENON. Species of the kopsi group are all dwarfed whereas those of the arel group are large. Still their otoliths depict a number of specialized features (see earlier) which they share with each other and they are therefore placed together in one group. In some of the specialized features otoliths of this group resemble those of the genus Symphurus. MENON’s ogilbyi complex of the kopsi group exhibits quite a different otolith pattern and is placed in the subgenus Icania. The last subgenus is Icania, comprising MENON’s cynoglossus and carpentari groups and his ogilbyi complex from the kopsi group. Again species of the cynoglossus group are dwarfed, those of the carpentari group are not. By means of otoliths this is probably the most diverse, least well defined subgenus and some of its members show the most specialized otolith morphology in this genus. Also it seems to me that this group could reasonably be split up into two or even three separate groups (or subgenera). C. lida of MENON’s cynoglossus group is already removed and placed in the subgenus Trulla. The roughly triangular shaped otoliths of the dwarfed ogilbyi complex and the puncticeps complex of MENON look just like small specimens of members of the subgenus Trulla, where they could be placed alterna- tively. MENON’s cynoglossus and monopus complexes show some special features such as the nearly flat inner face and the tendency to smoothen the outline of the sulcus. This character is further developed in MENON’s carpentari group to an ovally shaped sulcus outline (sulcus is also deepened), which is very untypical for a cynoglossid otolith. Again this is a very specialized feature which could be interpreted to separate the carpentari group from the subgenus Icania altogether. Unfortunatelly, otoliths are not known from the two of the other species in this group (paratypes of C. acutirostris in the BMNH collection were found to have otoliths dissolved by formalin). Recently, otoliths of C. marleyi have been figured by SMALE et al. (1995) and they indeed closely resemble those of C. carpentari. On the other hand, the otolith pattern of C. monopus could be interpreted as some kind of plesiomorphic character state from which the carpentari group evolved. Species and distribution: Including Paraplagusia as a subgenus, Cynoglossus contains some 54 valid species. In alphabetic order they are the following: C. abbreviatus, C. acutirostris, C. arel, C. attenuatus, C. bilineatus, C. blochi, C. borneensis, C. broadhursti, C. browni, C. cadenati, C. canariensis, C. capensis, C. carpentari, C. cynoglossus, C. dispar, C. dollfusi, C. dubius, C. durbanensis, C. ecaudatus, C. feldmanni, C. gilchristi, C. gracilis, C. heterolepis, C. interruptus, C. itinus, C. japonicus, C. joyneri, C. kapuasensis, C. kopsi, C. lachneri, C. lida, C. lingua, C. macrophthalmus, C. macrostomus, C. maculipinnis, C. marleyi, C. microlepis, C. microphthalmus, C. monodi, C. monopus, C. ogilbyi, C. puncticeps, C. quadrilineatus, C. robustus, C. sealarki, C. semifasciatus, C. semilaevis, C. senegalensis, C. sinusarabici, C. suyeni, C. trigrammus (regarded as synonym of C. abbreviatus by MENON), C. unicolor (regarded as synonym of C. bilineatus by MENON), C. waandersi, C. zanzibarensis. In addition there are two fossil records – C. leuchsi from the Miocene of Europe and C. obliqueventralis from the Pliocene of NW-Africa. The fishes of the genus Cynoglossus are widely distributed through the Indo-West Pacific and along the shores of Australia and West Africa. One species – C. sinusarabici – has immigrated into the eastern Mediterranean by ‘Lessepsian migration’ from the Red Sea through the Suez Canal. Schwarzhans: Pleuronectiformes 343 904a 903 904c 904b 906 905c 905b 905a Figs. 903-904: Cynoglossus (Trulla) canariensis STEINDACHNER 1882 – 10 × Figs. 905-906: Cynoglossus (Trulla) obliqueventralis n.sp. – 10 × Cynoglossus (Trulla) canariensis STEINDACHNER 1882 Figs. 903-904 syn. Cynoglossus lagoensis REGAN 1915 Investigated otoliths: 2 otoliths (left and right side) from off Luanda, Angola, ZMH Ot. 27.6. 1995.1-2 (leg. ZMH 20180). Discussion: A species with a massive, rounded predorsal projection, a deep postventral corner and a rather wide ostium. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: West Africa, Canary Islands, Senegal to Angola. Cynoglossus (Trulla) obliqueventralis n.sp. Figs. 905-906 Name: Referring to the steeply inclined anterior-ventral rim. Holotype: Fig. 905, SMF P 9327. Type-locality: Right river banks of the Oued Beth, ca. 1 km south of Dar Bel Hamri, NW-Morocco. Age: Lumachelle at the base of the Sands of Dar Bel Hamri, Lower Pliocene. 344 Paratypes: 1 otolith (fig. 906), topo- and stratitypic, SMF P 9328. Diagnosis: Large, very high bodied otoliths (index l:h 0.80-0.85). Predorsal projection broadly rounded, anterior-ventral rim steeply inclined, postventral corner very strongly developed. Description: Outline: Thin, very high otoliths with a broadly rounded predorsal projection, a moderate postdorsal angle, a steeply inclined anterior-ventral rim, a very strong postventral corner and a vertically cut, straight to slightly concave posterior rim. All rims smooth. Inner face: Smooth and considerably convex, particularly in the vertical direction. Sulcus “hammer” shaped, shallow, with pseudoostial opening, anteriorly moderately wide, posteriorly much widened. Colliculi completely fused. Circumsulcal depression indistinct, rather shallow, postventrally and dorsally somewhat widened. Other views: Rims sharp. Outer face concave, smooth. Discussion: This is the most highly bodied otolith of the genus Cynoglossus. Also the outline of the otolith is highly characteristic as described in the diagnosis. C. obliqueventralis probably is related to C. canariensis. Cynoglossus (Trulla) dubius DAY 1873 Figs. 907-908 Investigated otoliths: 2 otoliths (left and right side) from Karachee, India, ZMH Ot.27.6.1995.3 (leg. BMNH 1911.12.6.16) and BMNH 1911.12. 6.16. Discussion: A rather elongate otolith with a characteristically hooked predorsal projection. Distribution: West coast of India. Cynoglossus (Trulla) borneensis (BLEEKER 1858) Figs. 909-911 ?syn. Plagusia trulla CANTOR 1850 syn. Trulla cantori KAUP 1858 syn. Cynoglossus sinicus WU 1932 Investigated otoliths: 3 otoliths (1 left and 2 right side) from Singapore, ZMH Ot.27.6.1995.4-5 (leg. BMNH 1933.7.31.28-29) and BMNH 1933.7.31.2829). Discussion: Very similar to C. dubius but more compressed. Distribution: Borneo, Malaya, Thailand and South China Sea. Cynoglossus (Trulla) senegalensis (KAUP 1858) Fig. 912 syn. Cynoglossus goreensis STEINDACHNER 1882 syn. Cynoglossus simulator CHABANAUD 1949 Investigated otoliths: 1 otolith (right side), ZMH Ot.27.6.1995.6 (leg. ZMH 20180). Discussion: A moderately compressed otolith with a rather feeble postventral corner and a shallow and broad predorsal projection. Distribution: West Africa, Senegal to Nigeria. Cynoglossus (Trulla) quadrilineatus (BLEEKER 1851) Figs. 913-914 syn. Achirus bilineatus LACEPEDE 1802 (non Pleuronectes bilineatus BLOCH 1787) syn. Cynoglossus lineolatus STEINDACHNER 1867 syn. Cynoglossus quinquelineatus DAY 1877 syn. Cynoglossus sindensis DAY 1877 syn. Arelia diplasios JORDAN & EVERMANN 1903 Remarks: Following the inclusion of Paraplagusia as a subgenus in Cynoglossus, C. (Trulla) bilineatus (LACEPEDE 1802) becomes preoccupied by C. (Paraplagusia) bilineatus (BLOCH 1787). Investigated otoliths: 2 otoliths (left and right side) from northern Australia, ZMH Ot.27.6. 1995. 7-8 (leg. WAM). Schwarzhans: Pleuronectiformes 345 908a 907a 908c 908b 910a 909 911 910c 910b 912c 912b 912a Figs. 907-908: Cynoglossus (Trulla) dubius DAY 1873 – 10 × Figs. 909-911: Cynoglossus (Trulla) borneensis (BLEEKER 1858) – 10 × Fig. 912: Cynoglossus (Trulla) senegalensis (KAUP 1858) – 10 × Discussion: These otoliths are characterized by their extremely wide and somewhat deepened sulcus. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Distribution: Widely distributed through the Indo-West Pacific from Pakistan to Japan and southward to Australia. 346 914a 914c 913a 913b 914b 915 916b 916a 916c Figs. 913-914: Cynoglossus (Trulla) quadrilineatus (BLEEKER 1851) – 10 × Figs. 915-916: Cynoglossus (Trulla) lida (BLEEKER 1851) – 10 × Cynoglossus (Trulla) lida (BLEEKER 1851) Figs. 915-916 syn. Plagusia polytaenia BLEEKER 1853 syn. Cynoglossus intermedius ALCOCK 1889 syn. Cynoglossus os FOWLER 1904 Investigated otoliths: 2 otoliths (left and right side), Ganjam coast, India, ZMH Ot.27.6.1995.9 (leg. BMNH 1928.3.20.131) and BMNH 1928. 3.20.131. Discussion: Similar to C. quadrilineatus, specially as far as the sulcus is concerned, but with a more gently curving outline and a conspicuous concavity at the anterior-ventral rim. Distribution: East coast of Africa and Pakistan to Philippines. Cynoglossus (Dexiourius) kapuasensis FOWLER 1905 Figs. 917-918 Investigated otoliths: 2 otoliths (right side) from Sarawak, Borneo, ZMH Ot.27.6.1995.10 (leg. BMNH 1906.10.29.39-40) and BMNH 1906.10. 29.39-40. Discussion: Characteristic is the sharply deepened postdorsal portion of the circumsulcal depression. Distribution: Western Borneo, entering the Kapuas river. Cynoglossus (Dexiourius) heterolepis WEBER 1910 Fig. 919 Investigated otoliths: 1 otolith (right side) from the Upper Fly river, Papua New Guinea, BMNH 1933.2.17.1. Schwarzhans: Pleuronectiformes 347 917 918a 918b 918c 919a 919c 920c 920a 920b 919b Figs. 917-918: Cynoglossus (Dexiourius) kapuasensis FOWLER 1905 – 10 × Fig. 919: Cynoglossus (Dexiourius) heterolepis WEBER 1910 – 10 × Fig. 920: Cynoglossus (Dexiourius) feldmanni (BLEEKER 1853) – 10 × Discussion: Untypically otolith with a very shallow ventral rim and a very smooth and convex inner face. Also otolith rather thickset. Distribution: Thailand, Cambodia, Borneo and Sumatra, entering into rivers. Distribution: New Guinea and northern Australia, entering into rivers. Cynoglossus (Dexiourius) semilaevis GÜNTHER 1873 Fig. 921 Cynoglossus (Dexiourius) feldmanni (BLEEKER 1853) Fig. 920 syn. Arelia rhomaleus JORDAN & STARKS 1906 syn. Cynoglossus roulei WU 1932 syn. Cynoglossus hardenbergi NORMAN 1931 syn. Cynoglossus abentoni STAUCH 1966 Investigated otoliths: 1 otolith (right side) from Thailand, BMNH 1989.11.20.2. Discussion: Otolith high, with nearly triangular outline and slightly deepened postdorsal portion of the circumsulcal depression. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 1 otolith (right side) from Chekiang, China, BMNH 1930.7.28.13. Discussion: Otolith with rounded caudal tip. Otherwise very similar to C. gracilis but may be slightly more elongate. Distribution: China. 348 Cynoglossus (Dexiourius) gracilis GÜNTHER 1873 Fig. 922 Cynoglossus (Paraplagusia) aff. dispar DAY 1877 Figs. 928-929 syn. Cynoglossus microps STEINDACHNER 1898 syn. Areliscus hollandi JORDAN & METZ 1913 syn. Cynoglossus pellegrini WU 1932 Investigated otoliths: 2 otoliths (left and right side) from the Seychelles, ZMH Ot.27.6.1995.15 (leg. BMNH 1869.3.1.30-31) and BMNH 1869.3.1. 30-31. Investigated otoliths: 1 otolith (right side) from Chekiang, China, BMNH 1930.7.28.12. Discussion: Otolith with rounded caudal tip. Very similar to C. semilaevis. Distribution: Korea and China. Cynoglossus (Dexiourius) abbreviatus (GRAY 1835) Figs. 923-924 syn. Areliscus purpureomaculatus REGAN 1905 Discussion: Inner face convex, smooth, with sharp and narrow circumsulcal depression. Posterior rim concave. Predorsal projection reduced. – MENON (1977) placed this species in his canariensis group (here subgenus Trulla) but otoliths are very alike those found in other species of the subgenus Paraplagusia. The presence of lateral line on the blind side is different and thus the supposed re-arrangement needs to be verified by other ichthyological investigations. – However, it is also possible, that this specimen not investigated by MENON rather represents C. bilineatus. It also originates from a different geographical location than the type specimens. Investigated otoliths: 2 otoliths (right side) from Kiautshou, China, ZMH Ot.27.6.1995.11-12 (leg. ZMH 20158). Distribution: Seychelles (?), Pakistan and India. Discussion: Otolith with rounded caudal tip. Typical is the fine marginal crenulation and the very convex and smooth inner face. Cynoglossus (Paraplagusia) japonicus (TEMMINCK & SCHLEGEL 1842) Figs. 930-931 Distribution: Korea, Japan, Taiwan, China. Cynoglossus (Dexiourius) trigrammus GÜNTHER 1862 Figs. 925-927 Investigated otoliths: 3 otoliths (1 left and 2 right side) from the Canton coast, China, ZMH Ot.27.6.1995.13-14 (leg. BMNH 1930.7.28.10-11) and BMNH 1930.7.28.10-11. Discussion: Otolith with rounded caudal tip. Similar to C. gracilis but with more smooth rims and less convex inner face. – MENON (1977) placed C. trigrammus in synonymy with C. abbreviatus, but otoliths indicate that it should be kept as a separate species. Distribution: China. Investigated otoliths: 2 otoliths (left and right side) from Enchu Nada, Central Japan, coll. Ohe #78726-35. Discussion: Similar to C. bilineatus but with a less reduced predorsal projection. Distribution: Korea, Japan and South China. Cynoglossus (Paraplagusia) bilineatus (BLOCH 1787) Fig. 932 syn. syn. syn. ?syn. ?syn. ?syn. Plagusia dipterygia RÜPPELL 1828 Paraplagusia macrocephalus BLEEKER 1875 Plagusia acuminata CASTELNAU 1875 Plagusia guttata MACLEAY 1878 Plagusia notata DE VIS 1883 Plagusia brevirostris KENT 1893 Schwarzhans: Pleuronectiformes 349 921a 921c 922c 921b 922a 922b 923a 923c 924a 924b 923b 926 925 927b 927a 927c Fig. 921: Cynoglossus (Dexiourius) semilaevis GÜNTHER 1873 – 15 × Fig. 922: Cynoglossus (Dexiourius) gracilis GÜNTHER 1873 – 15 × Figs. 923-924: Cynoglossus (Dexiourius) abbreviatus (GRAY 1853) – 10 × Figs. 925-927: Cynoglossus (Dexiourius) trigrammus GÜNTHER 1862 – figs. 925-926 = 10 ×; fig. 927 = 15 × syn. Plagusia robinsoni REGAN 1919 ?syn. Rhinoplagusia australis RENDAHL 1921 syn. Rhinoplagusia formoana OSHIMA 1927 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 1 otolith (right side) from off Kochi, Japan, ZMH Ot.27.6.1995.16 (leg. Sasaki). 350 928a 928c 929 928b 931b 931a 930c 930a 930b 932c 932a 932b 934c 933a 933b 934a 934b Figs. 928-929: Cynoglossus (Paraplagusia) aff. dispar DAY 1877 – 10 × Figs. 930-931: Cynoglossus (Paraplagusia) japonicus (TEMMINCK & SCHLEGEL 1842) – 10 × Fig. 932: Cynoglossus (Paraplagusia) bilineatus (BLOCH 1787) – 10 × Fig. 933: Cynoglossus (Paraplagusia) blochi BLEEKER 1875 – 15 × Fig. 934: Cynoglossus (Paraplagusia) unicolor MACLEAY 1882 – 10 × Discussion: Very similar to C. dispar and C. japonicus. Distinguished from the latter by the reduced predorsal projection. Distribution: Widely distributed throughout the Indo-West Pacific, from East Africa through the Indian Ocean to China and Australia(?). Schwarzhans: Pleuronectiformes 351 936b 935 936a 936c 938 939a 937 940 939b Figs. 935-940: Cynoglossus (Cynoglossus) arel (SCHNEIDER 1801) – 10 × Cynoglossus (Paraplagusia) blochi BLEEKER 1875 Fig. 933 Cynoglossus (Cynoglossus) arel (SCHNEIDER 1801) Figs. 935-940 Investigated otoliths: 1 otolith (right side) from Calcutta, India, BMNH 1933.1.2.5. syn. Cynoglossus melampetalus RICHARDSON 1846 syn. Plagusia grandisquamis CANTOR 1850 syn. Plagusia macrolepidota BLEEKER 1851 syn. Plagusia cantoris BLEEKER 1853 syn. Plagusia oligolepis BLEEKER 1854 syn. Cantoria pinangensis KAUP 1858 syn. Arelia kaupii BLEEKER 1860 syn. Cynoglossus elongatus GÜNTHER 1862 Discussion: Otolith rather elongate. Distribution: Pakistan to the Malay Archipelago and Australia. Cynoglossus (Paraplagusia) unicolor MACLEAY 1882 Fig. 934 Investigated otoliths: 1 otolith (right side) from Western Australia, ZMH Ot.27.6.1995.17 (leg. WAM). Discussion: Similar to C. japonicus but may be more elongate. The presence of the predorsal angle distinguishes this otolith from C. bilineatus, which is also the reason why I kept the Australian specimens separate, contrary to MENON (1979). Distribution: Australia. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Investigated otoliths: 7 otoliths (3 left and 4 right side), 4 otoliths identified as C. macrolepidotus (figs. 935-938) from the Persian Gulf, ZMH Ot.27.6. 1995.18-20 (leg. BMNH 1928.3.20.89-90) and BMNH 1928.3.20.89-90, 2 otoliths identified as C. melampetalus (figs. 939-940) from Amoy, China, ZMH Ot.27.6.1995.21 (leg. BMNH 1924.12. 15.82-86) and BMNH 1924.12.15.82-86), 1 otolith (not figured) identified as C. arel from Indonesia, BMNH 1968.9.8.13-14. Discussion: Otoliths large. Predorsal projection massive. Sulcus with narrowed, pointed anterior tip. Similar to C. robustus and C. lingua but more compressed. Those specimens identified as C. me- 352 941a 941c 942b 942a 941b 945a 943 945c 944 945b Figs. 941-942: Cynoglossus (Cynoglossus) robustus GÜNTHER 1873 – 10 × Figs. 943-945: Cynoglossus (Cynoglossus) lingua HAMILTON-BUCHANAN 1822 – 10 × lampetalus are more regular in outline and with a less pronounced predorsal projection. Distribution: Persian Gulf to India and to the South China Sea, the Philippines and Taiwan. Cynoglossus (Cynoglossus) robustus GÜNTHER 1873 Figs. 941-942 syn. Cynoglossus brunneaus REGAN 1905 syn. Cynoglossus inusita JORDAN, TANAKA & SNYDER 1913 Investigated otoliths: 2 otoliths (left and right side) from Japan, ZMH Ot.27.6.1995.22 (leg. BMNH 1960.5.13.1-2) and BMNH 1960.5.13.1-2. Discussion: Similar to C. arel and C. lingua, with a very pronounced predorsal projection. Distribution: Korea, Japan, Taiwan and China. Cynoglossus (Cynoglossus) lingua HAMILTON-BUCHANAN 1822 Figs. 943-945 syn. Pleuronectes potous CUVIER 1836 syn. Plagusia macrorhynchos BLEEKER 1851 syn. Cynoglossus acinaceus JENKINS 1910 Schwarzhans: Pleuronectiformes 353 948a 946 947a 947b 949a 949b 948b Figs. 946-949: Cynoglossus (Cynoglossus) joyneri GÜNTHER 1878 – 10 × Investigated otoliths: 3 otoliths (1 left and 2 right side) from Singapore, ZMH Ot.27.6.1995.23-24 (leg. BMNH 1933.7.31.24-26) and BMNH 1933.7.31.24-26. Discussion: Very similar to C. arel and C. robustus but somewhat more elongate. Distribution: Pakistan and India to Thailand and Vietnam. Investigated otoliths: 4 otoliths (2 left and 2 right side) from off Kochi, Japan, ZMH Ot.27.6.1995.2528 (leg. Sasaki). Discussion: Small, compressed otoliths with nearly triangular outline. Inner face convex. Sulcus anteriorly not much narrowed. Circumsulcal depression bilobate. Distribution: Japan and Hong Kong. Cynoglossus (Cynoglossus) joyneri GÜNTHER 1878 Figs. 946-949 Cynoglossus (Cynoglossus) kopsi (BLEEKER 1851) Figs. 954-958 syn. Cynoglossus lighti NORMAN 1925 syn. Areliscus tenuis OSHIMA 1927 syn. Cynoglossus tshusanensis CHABANAUD 1951 syn. syn. syn. syn. Investigated otoliths: 4 otoliths (2 left and 2 right side) from Japan, coll. Ohe #76424-26 and #8207102A. Investigated otoliths: 5 otoliths (1 left and 4 right side), 3 otoliths identified as C. kopsi (figs. 954, 955, 958) from the Arafura Sea, ZMH Ot.27.6.1995.29-30 (leg. BMNH 90.2.26.148) and BMNH 79.5.4.81, 2 otoliths identified as C. brachycephalus (figs. 956-957) from India, ZMH Ot.27.6.1995.31-32 (leg. BMNH 1908.3.23.149-52). Discussion: Small, rather elongate otoliths, with not much anteriorly narrowed sulcus. Inner face rather flat. Circumsulcal depression incipiently bilobate. Distribution: Korea, Japan, Taiwan and China. Cynoglossus (Cynoglossus) itinus (SNYDER 1909) Figs. 950-953 syn. Cynoglossus punctatus SHEN 1969 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Cynoglossus Cynoglossus Cynoglossus Cynoglossus brachycephalus BLEEKER 1875 praecisus ALCOCK 1890 versicolor ALCOCK 1890 sibogae WEBER 1913 Discussion: Similar to C. itinus but with anteriorly narrowed and pointed sulcus. Distribution: Indo-Australian Archipelago and from Persian Gulf and India to the Philippines and Taiwan. 354 952a 950 953a 953c 952b 951 953d 953b 954 955b 955a 956 955c 955d 957 958 959 960 Figs. 950-953: Cynoglossus (Cynoglossus) itinus (SNYDER 1909) – 10 × Figs. 954-958: Cynoglossus (Cynoglossus) kopsi (BLEEKER 1851) – 10 × Figs. 959-960: Cynoglossus (Cynoglossus) interruptus GÜNTHER 1880 – 10 × Cynoglossus (Cynoglossus) interruptus GÜNTHER 1880 Figs. 959-960 syn. Cynoglossus nigropinnatus OCHIAI 1959 Investigated otoliths: 2 otoliths (right side) from Wakanoura, Japan, ZMH Ot.27.6.1995.33 (leg. BMNH 1923.2.26.660-7) and BMNH 1923.2.26.6607). Discussion: Very similar to C. kopsi but may be more compressed. Distribution: Japan. Schwarzhans: Pleuronectiformes 355 963a 961 963d 962 964 965b 963c 963b 965a 965c Figs. 961-963: Cynoglossus (Cynoglossus) sealarki REGAN 1908 – 10 × Figs. 964-965: Cynoglossus (Cynoglossus) zanzibarensis NORMAN 1939 – 10 × Cynoglossus (Cynoglossus) sealarki REGAN 1908 Figs. 961-963 Investigated otoliths: 3 otoliths (paratypes, 1 left and 2 right side) from Saya de Malha Bank, ZMH Ot.27.6.1995.34-35 (leg. BMNH 1908.3.23.153-6) and BMNH 1908.3.23.153-6. (leg. BMNH 1939.5.24.1812-14) and BMNH 1939.5. 24.1812-14. Discussion: Very similar to C. sealarki and may be not distinguishable by means of otoliths. Distribution: Durban, South Africa, through Zanzibar to Kenya. Discussion: Moderately large, compressed, rather thickset otoliths with rather gently curving outline. Sulcus anteriorly narrowed and pointed. Circumsulcal depression bilobate. Cynoglossus (Icania) broadhursti WAITE 1905 Figs. 966-967 Distribution: Saya de Malha Bank. Investigated otoliths: 2 otoliths (left and right side) from Western Australia, ZMH Ot.28.6.1995. 1-2 (leg. WAM). Cynoglossus (Cynoglossus) zanzibarensis NORMAN 1939 Figs. 964-965 Investigated otoliths: 2 otoliths (syntype, left and right side) from Zanzibar, ZMH Ot.27.6.1995.36 Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: Medium sized, high otoliths with roughly triangular outline. Cauda very wide, ostium anteriorly not narrowed. Circumsulcal depression faint, narrow. Distribution: Western and southern Australia. 356 Cynoglossus (Icania) maculipinnis RENDAHL 1921 Figs. 968-969 Distribution: From India through the Malay Archipelago to the Philippines, the South China Sea and Japan and southward to northwest Australia. syn. Cynoglossus maccullochi NORMAN 1926 Investigated otoliths: 2 otoliths (left and right side), identified as C. maccullochi from Western Australia, ZMH Ot.28.6.1995.3-4 (leg. WAM). Cynoglossus (Icania) leuchsi WEINFURTER 1952 Figs. 976-980 Discussion: Small, high otoliths with roughly triangular outline. Cauda moderately wide, ostium anteriorly not narrowed. Circumsulcal depression narrow. syn. Scopelus? sp. – PRIEM 1914: fig. 8 syn. Cynoglossus leuchsi WEINFURTER 1952 – WEINFURTER 1952: pl. 4, figs. 1-3 syn. Rhinoplagusia altus – LAFOND-GRELLETY 1967: pl. 11, fig. 52 (nomen nudum) syn. Rhinoplagusia sp. – JONET 1973: pl. 4, fig. 137 syn. Rhinoplagusia leuchsi – JONET 1973: pl. 4, fig. 138 syn. genus Cynoglossidarum sp. – STEURBAUT 1979: pl. 11, fig. 11 syn. Paraplagusia roseni NOLF & CAPPETTA 198 – NOLF & CAPPETTA 1980: pl. 3, figs. 19-21 syn. Paraplagusia alta STEURBAUT & JONET 1981 – STEURBAUT & JONET 1981: pl. 5, figs. 10-13 syn. Paraplagusia alta – STEURBAUT 1984: pl. 36, figs. 11-14 syn. Cynoglossus altus MENZEL 1986 – MENZEL 1986: pl. 9, fig. 2, pl. 10, fig. 7 Distribution: Western and northern Australia and Queensland. Cynoglossus (Icania) gilchristi REGAN 1920 Fig. 970 Investigated otoliths: 1 otolith (right side) from the Rufiji delta, Tanzania, BMNH 1981.6.25.102108. Discussion: Similar to C. maculipinnis, but with somewhat smoothed outline of sulcus. Similar to C. puncticeps, but less high. Distribution: South Africa to Madagascar and Tanzania. Cynoglossus (Icania) puncticeps RICHARDSON 1846 Figs. 971-975 syn. syn. syn. syn. syn. syn. Plagusia nigrolabeculata RICHARDSON 1846 Plagusia aurolimbata RICHARDSON 1846 Plagusia javanica BLEEKER 1851 Plagusia brachyrhynchus BLEEKER 1851 Cynoglossus brevis GÜNTHER 1862 Cynoglossus immaculatus PELLEGRIN & CHEVEY 1940 Investigated otoliths: 5 otoliths ( 1 left and 4 right side) from Singapore, ZMH Ot.28.6.1995.5-8 (leg. BMNH 1934.11.21.1-8) and BMNH 1934.11.21.18. Discussion: Very similar to C. gilchristi, but somewhat higher. Investigated otoliths: 5 otoliths, the holotype of C. leuchsi (fig. 977) from Wetzelsteffi near Wetzelsdorf, Austria, Middle Miocene, LMJ, 2 paratypes of C. leuchsi (figs. 979-980) from Mühlbauer near St. Florian, Austria, Middle Miocene, LMJ, the holotype of C. altus MENZEL (fig. 978) from the well UE 12 Gräpl near Mulsum, northern Germany, Hemmoorian, Lower Miocene, NLH 11735, 1 otolith (fig. 976) from the Hörstgen 4 shaft, northwest Germany, Hemmoorian, Lower Miocene, SMF P (coll. Anderson). Ontogeny and variability: The small paratypes of C. leuchsi are more gently rounded in outline, but the predorsal projection is more strongly developed. Otoliths of this species vary somewhat in outline. The postventral corner, the predorsal projection and the postdorsal angle can all be developed more broadly rounded or more angular. This and the wide geographic distribution of the species in the Miocene of Europe probably is the reason for the extended synonymy list. Schwarzhans: Pleuronectiformes 357 967a 966 967c 967b 969a 969c 968 970c 970a 969b 970b 973 972c 971 972a 972b 974 975b 975a Figs. 966-967: Cynoglossus (Icania) broadhursti WAITE 1905 – 10 × Figs. 968-969: Cynoglossus (Icania) maculipinnis RENDAHL 1921 – 10 × Fig. 970: Cynoglossus (Icania) gilchristi REGAN 1920 – 15 × Figs. 971-975: Cynoglossus (Icania) puncticeps RICHARDSON 1846 – 15 × Piscium Catalogus, Part Otolithi piscium, Vol. 2 358 976a 977a 976b 978 977b 980 979 Figs. 976-980: Cynoglossus (Icania) leuchsi WEINFURTER 1952 – 15 × Discussion: Very similar to the recent C. gilchristi and C. puncticeps, but usually with a more regularly curving outline. Distribution: Lower and Middle Miocene of Austria, France (Aquitaine and Mediterranean Basins), Portugal and northern Germany. Cynoglossus (Icania) cynoglossus (HAMILTON-BUCHANAN 1822) Fig. 981 Cynoglossus (Icania) semifasciatus DAY 1877 Fig. 982 syn. Cynoglossus brevirostris DAY 1877 Investigated otoliths: 1 otolith (right side) from the Ganjam coast, India, BMNH 1928.3.20.107. Discussion: Hardly distinguishable from C. cynoglossus by means of otoliths. Distribution: Eastern India and Ceylon. syn. syn. syn. syn. syn. syn. Plagusia oxyrhynchos BLEEKER 1851 Plagusia sumatrana BLEEKER 1853 Plagusia bengalensis BLEEKER 1853 Cynoglossus hamiltonii GÜNTHER 1862 Cynoglossus buchanani DAY 1869 Cynoglossus deltae JENKINS 1910 Investigated otoliths: 1 otolith (right side) from Singapore, BMNH 1933.12.27.5. Discussion: Small, moderately compressed otoliths with rather flat inner face. Sulcus with tendency to smoothed outline. Circumsulcal depression rather wide. Distribution: Western India to Malay Archipelago and the Philippines. Cynoglossus (Icania) monopus (BLEEKER 1849) Fig. 983 syn. Plagusia melanopterus BLEEKER 1851 syn. Arelia ceratophrys KAUP 1858 Investigated otoliths: 1 otolith (right side) from Singapore, BMNH 1984.1.12.91-93. Discussion: Similar to C. cynoglossus and C. semifasciatus, but unique for its extremely narrow cauda (very low index ch:oh). Distribution: From the Bay of Bengal through the Malay Archipelago to Hong Kong. Schwarzhans: Pleuronectiformes 359 983a 981a 981b 982a 981c 982b 983c 982c 983b Fig. 981: Cynoglossus (Icania) cynoglossus (HAMILTON-BUCHANAN 1822) – 15 × Fig. 982: Cynoglossus (Icania) semifasciatus DAY 1877 – 15 × Fig. 983: Cynoglossus (Icania) monopus (BLEEKER 1849) – 15 × Cynoglossus (Icania) carpentari ALCOCK 1889 Figs. 984-989 Investigated otoliths: 6 otoliths (2 left and 4 right side), 4 otoliths from the Bay of Bengal (figs. 984987), ZMH Ot.28.6.1995.9-11 (leg. BMNH 1928. 3.20.75-77) and BMNH 1928.3.20.75-77 and 2 otoliths from the Gulf of Oman (figs. 988-989), ZMH Ot.28.6.1995.12-13 (leg. BMNH 1939.5.24.1799). Discussion: Otoliths of this species are unique amongst the genus Cynoglossus for a number of characters. They are small (also as compared to the size of the fishes), rather elongate, thickset, with a flat inner face and a concave outer face. The sulcus is reduced to a completely ovale shape, considerably deepened and terminating at some distance from the anterior rim of the otolith. The circumsulcal depression is regularly curved, considerably deepened and runs rather close to the sulcus. The otoliths of the specimen from the Gulf of Oman (type B, figs. 988-989) differ slightly from those of the Bay of Bengal (type A, figs. 984-987) in being more thin and compressed and showing an even smaller sulcus. SMALE et al. (1995) figured otoliths of the related species C. marleyi, wich indeed in all aspects closely resemble those of C. carpentari, in particular as far as the sulcus morphology is concerned. Main difference seems to be the slightly convex inner face and the more rectangular outline. However, these findings further support the special position of this little group within the Piscium Catalogus, Part Otolithi piscium, Vol. 2 genus Cynoglossus and, in my opinion, warrants their distinction as a distinctive subgenus. Distribution: Persian Gulf to the Bay of Bengal, in rather deep water. 7.9.2 Symphurus Group Genera: One genus – Symphurus – widely distributed throughout the tropical and subtropical world oceans in shallow to relatively deep water on the continental shelfs and slopes. Definition and relationship: Otoliths of the Symphurus Group are typical representatives of the family Cynoglossidae with its “hammer” shaped sulcus. However, differing from the Cynoglossus Group, the sulcus is somewhat reduced anteriorly. Further specializations are as follows. The ventral rim is gently and regularly curving, not very deep, whereas the dorsal rim is usually higher and shifted backwards. Thus the otoliths are almost symmetrical along the horizontal axis, which sometimes may cause difficulties to distinguish between left and right otoliths, especially when found isolated as in the fossil record. Most notable though is the strange development of the circumsulcal depression. It is considerably widened and deepened postdorsally and postventrally (bilobate) to an extent where it almost meets the dorsal and ventral tips of the much widened cauda. In most ichthyological literature Symphurus is regarded as the plesiomorphic sister group of 360 Cynoglossus (and Paraplagusia), mostly because of its not hooked and terminal snout, the still present but rudimentary pectoral fins and the pelvic fin, which is free from the anal fin (see MENNON, 1977 and CHAPLEAU, 1987). However, lateral lines are absent from both sides. The otoliths instead point to a completely different story. The further and very peculiar specialization of its morphology (see above) rather indicates Symphurus to represent an apomorphic group within the Cynoglossidae. It must be questioned if not at least some of the seemingly plesiomorphic morphological characters of the fishes rather represent some kind of secondary reduction. Symphurus RAFINESQUE 1810 Type-species: Symphurus nigrescens RAFINESQUE 1810 syn. Odontolepis FISCHER 1813 (type-species: S. nigrescens) syn. Plagusia CUVIER 1816 (type-species: Pleuronectes plagusia, pre-occupied) syn. Bibronia COCCO 1844 (type-species: B. ligulata) syn. Plagiusa BONAPARTE 1846 (type-species: P. lactea, syn. S. nigrescens, substitute for Plagusia) syn. Eupnoea GISTEL 1848 (type-species: Plagusia lactea, syn. S. nigrescens) syn. Euporista GISTEL 1848 (substitute for Plagusia) syn. Aphorista KAUP 1858 (type-species: Achirus ornatus, syn. S. plagusia) – subgenus syn. Glossichthys GILL 1861 (type-species: Pleuronectes plagusia) syn. Ammopleurops GÜNTHER 1862 (type-species: Plagusia lactea, syn. S. nigrescens) syn. Bascanius SCHIÖDTE 1867 (type-species: B. taedifer, larval) syn. Acedia JORDAN 1888 (type-species: Aphorista nebulosa) Diagnosis: Moderately thin to thickset, high bodied otoliths; ventral rim moderately deep and rather regularly curving, dorsal rim usually more high, with an inclined predorsal portion and a massive, rounded postdorsal portion, anterior rim broadly rounded, posterior rim high, oblique or vertically cut, with or without concavity, or broadly rounded. Otoliths small, up to 3 mm. Sulcus usually shallow, occasionally slightly deepened, with fused colliculi, typical “hammer” shaped outline, often with smoothed outline, anteriorly reduced. Circumsulcal depression well developed, narrow, often furrow like, postdorsally and postventrally widened to nearly reach the dorsal and ventral tips of the cauda (bilobate), running close to the otolith rims. Inner face moderately convex to nearly flat, usually rather smooth; outer face flat to markedly convex, usually smooth. Rims moderately sharp, sometimes thickset, not or only faintly ornamented. Subgeneric definitions: So far otoliths have only be investigated from 15 species of the extant 72 nominal species of the genus. It may thus seem premature to formulate a detailed analysis of morphological clusters observed. Anyhow, otoliths of those species investigated fall into two quite well defined groups characterized in the following. However, more material should be awaited of additional species to support this concept once they get available or other ichthyological investigations to verify this grouping. Tentatively, the two distinctive groups are assigned to subgeneric ranking with names taken from the generic synonymy list. One group is characterized by very high otoliths with an outline as described in the above diagnosis. Also, they are usually quite thin and their sulcus is rather large. These species are placed in the formal subgenus Aphorista. So far, this pattern has only be found in new world species. The second group of species is placed in the formal subgenus Symphurus. These otoliths have an almost perfectly round outline. They are much more thickset and show a tendency to reduce the size of the sulcus. The latter is carried furthest in S. gilesi and S. nigrescens. The majority of species placed in this group are from the old world, but few new world species are tentatively included as well. With more material coming at hand it could be envisaged that this group is being split up further. Candidates for this are the two species mentioned above. The features separating the subgenus Symphurus from Aphorista are mainly due to reduction of certain characters. They are therefore thought to represent a more derived group. Schwarzhans: Pleuronectiformes 361 986 985 984 986c 986b 987a 988a 987c 989a 987b 989c 989b Figs. 984-989: Cynoglossus (Icania) carpentari ALCOCK 1889; figs. 984-987 morphotype A, figs. 988-989 morphotype B – 15 × Measurements: l:h h:t l:ol ch:oh con.i subgenus Aphorista plagusia 0.95 4.0 elongatus 0.85 4.4 chabanaudi 0.85 3.6 plagiusa 0.75 nm trewavasae 0.90-1.00 2.9 civitatus 0.90-0.95 3.4 oculellus 1.00 3.6 leei 0.90-0.95 3.8 atricaudus 0.85-0.90 2.8-3.0 2.0 2.1 2.1 1.9 1.8-2.3 1.9-2.1 2.4 2.0-2.2 1.8-2.2 2.4 2.5 2.4 3.5 2.1-2.4 2.2-2.4 3.6 2.5 1.7-2.4 3.5 4.4 3.2 nm 5.2 2.9 3.5 4.3 2.8 subgenus Symphurus williamsi 1.10 atramentatus 1.10 orientalis 1.00-1.05 septemstriatus 0.95-1.00 gilesi 0.95 nigrescens 1.00-1.05 2.4 2.6 2.7-2.8 2.6-2.8 3.2 2.8-2.9 2.5 1.8 2.8 1.5-1.8 1.8 nm 2.4 3.0 2.2 5.5 nm 3.3 2.3 2.7 2.0 2.9 nm 2.8 Side dimorphism: Usually not apparent. Occasional, otoliths of the left side show a slightly less high cauda. Variability: The variability level in the species of this genus apparently is quite different. In most species it seems to be very moderate and then distinction of even closely related species may not be very difficult. Few species, however, show extreme variations of the outline. S. atricaudatus is such a species with a very irregular outline. In such cases it becomes very difficult to find diagnostic characters on the species level. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Discussion: As stated before (see entry to Cynoglossidae and the Symphurus Group) otoliths of the genus Symphurus are characterized by a number of autapomorphic features, such as the anteriorly reduced sulcus, the bilobate circumsulcal depression and the backwardly shifted dorsal rim. Some of these characters are to certain extent foreshadowed in some members of the genus Cynoglossus (subgenus Cynoglossus). I therefore regard Symphurus as the more derived genus in the Cynoglossidae. Species and distribution: Unlike the genus Cynoglossus, Symphurus has so far not been subject to a comprehensive revision, although a number of regional revisions have been published (CHABANAUD 1956, GINSBURG 1951, MENEZES & BENVEGNU 1976, MUNROE 1990, 1991). There may be up to 72 nominally valid recent species in this genus and new species are constantly being described. Apparently, the high number of species is due to a very pronounced regionalization of the species in this genus. Also many species seem to be established on few specimens only and are difficult to come by for otolith extraction (hence only 15 species represented here). Furthermore, it was found while extracting otoliths from specimens of Symphurus that they were often dissolved by formalin. Possibly 362 990a 990c 990d 991c 991a 991d 991b 990b 992a 992d 992c 993 992b 994 Fig. 990: Symphurus (Aphorista) plagusia (BLOCH & SCHNEIDER 1801) – 10 × Fig. 991: Symphurus (Aphorista) elongatus (GÜNTHER 1869) – 10 × Figs. 992-993: Symphurus (Aphorista) chabanaudi MAHADEVA & MUNROE 1990– 10 × Fig. 994: Symphurus (Aphorista) plagiusa (LINNAEUS 1766) – 10 × they act more sensitive to formalin than those of other Pleuronectiformes. 72 nominally valid species are listed in the following (new and old world species listed separately). The list may not be complete. New world species: S. arawak, S. atramentatus, S. atricaudus, S. bergi, S. callopterus, S. caribbeanus, S. chabanaudi, S. civitatum, S. diabolicus, S. diomedianus, S. elongatus, S. fasciolaris, S. ginsburgi, S. gorgonae, S. jenynsi, S. kyaropterygium, S. leei, S. luzonensis, S. marginatus, S. melanurus, S. melasmatotheca, S. meridionalis, S. microlepis, S. minor, S. nebulosus, S. oculellus, S. oligomerus, S. ommaspilus, S.paitensis, S. parvus, S. pelicanus, S. piger, S. plagiusa, S. plagusia, S. prolatinaris, S. pterospilotus, S. pusillus, S. rhytisma, S. sumtuosus, S. tesselatus, S. trewavasae, S. undatus, S. undecimplerus, S. urospilos, S. varius, S. williamsi. Old world species: S. arabicus, S. australis, S. fallax, S. fuscus, S. gilesi, S. holothuriae, S. ligulatus, S.lubbocki, S. macrophthalmus, S. maldiviensis, S. marmoratus, S. nigrescens, S. normani, S. novemfasciatus, S. ocellatus, S. orientalis, S. regani, S. reticulatus, S. sayademalhensis, S. schultzi, S. septemstriatus, S. strictus, S. trifasciatus, S. variegatus, S. vittatus, S. woodmasoni. In the fossil record Symphurus otoliths have rarely been reported. Two specimens reported from the Miocene of Trinidad (NOLF, 1976) and the Miocene of the Dominican Republic (NOLF & STRINGER, 1992) are too poorly preserved for specific identification. A single specimen from the Pliocene of northern Morocco is tentatively assigned to the recent S. nigrescens. Symphurus (Aphorista) plagusia (BLOCH & SCHNEIDER 1801) Fig. 990 syn. Achirus ornatus LACEPEDE 1803 Investigated otoliths: 1 otolith (right side) from Trinidad (identified as S. ornatus), BMNH 94.5.8.6. Discussion: An otolith with a rather regularly curving outline and a rather large sulcus. Distribution: West Indies, south to Rio de Janeiro, in shallow water. Schwarzhans: Pleuronectiformes 363 995 998a 997 996 998c 998b 998d 999 Figs. 995-999: Symphurus (Aphorista) trewavasae CHABANAUD 1948 – 10 × Symphurus (Aphorista) elongatus (GÜNTHER 1869) Fig. 991 Investigated otoliths: 1 otolith (right side), ZMH Ot. 4.7.1995.1 (leg. ZMH 20195). Discussion: A thin otolith with a straight, vertically cut posterior rim and a markedly concave predorsal rim. Distribution: Pacific coast of tropical America. Symphurus (Aphorista) chabanaudi MAHADEVA & MUNROE 1990 Figs. 992-993 Investigated otoliths: 2 otoliths (right side), paratypes from the Gulf of California, ZMH Ot.4.7. 1995.2 (leg. BMNH 1956.3.1.6-14) and BMNH 19563.1.6-14. Discussion: Very similar to S. plagusia but somewhat more compressed. Distribution: Gulf of California. Symphurus (Aphorista) plagiusa (LINNAEUS 1766) Fig. 994 syn. Plagusia fasciata HOLBROOK 1842 Investigated otoliths: 1 somewhat eroded otolith (right side) from Rockport, USA, BMNH 1948.8.6.1374. Discussion: Extremely high and rather thickset otolith with an almost triangular sulcus outline. Distribution: South Atlantic and Gulf coast of the USA. Symphurus (Aphorista) trewavasae CHABANAUD 1948 Figs. 995-999 Investigated otoliths: 5 otoliths (1 left side and 4 right side), paratypes from Rio de Janeiro, Brazil, ZMH Ot. 4.7.1995.3-6 (leg. BMNH 1913.12. 4.264-73) and BMNH 1913.12.4.264-73. Discussion: Otoliths with a distinctly concave predorsal rim and a bluntly rounded posterior rim similar to S. elongatus, but more thickset and with a rather narrow cauda. Distribution: Atlantic coast of South America. Piscium Catalogus, Part Otolithi piscium, Vol. 2 364 1000a 1000d 1002a 1002c 1000c 1000b 1001 1002d 1002b Figs. 1000-1001: Symphurus (Aphorista) civitatum GINSBURG 1951 – 10 × Fig. 1002: Symphurus (Aphorista) oculellus MUNROE 1991 – 10 × Symphurus (Aphorista) civitatum GINSBURG 1951 Figs. 1000-1001 Symphurus (Aphorista) leei JORDAN & BOLLMAN 1889 Figs. 1003-1004 Investigated otoliths: 2 otoliths (right side) from Louisiana, USA, ZMH Ot.4.7.1995.7 (leg. BMNH 1931.11.5.76-81( and BMNH 1931.11.5.76-81. Investigated otoliths: 2 otoliths (left and right side) from the Pacific coast of Panama, ZMH Ot.4.7.1995.8 (leg. BMNH 1930.9.2.41) and BMNH 1930.9.2.41. Discussion: Similar to S. trewavasae, but without concave predorsal rim, with a pointed postdorsal angle and e regularly deepened sulcus. Distribution: Gulf coast, USA and Mexico, Bermudas, in moderately deep water. Symphurus (Aphorista) oculellus MUNROE 1991 Fig. 1002 Investigated otoliths: 1 otolith (right side), paratype from British Guyana, 8°30’N/59°02’W, BMNH 1961.9.4.117-118. Discussion: Similar to S. civitatum, but less compressed and with a somewhat pointed anterior tip. Distribution: Guyana and northeastern Brazil, in moderately deep water. Discussion: Very similar to S. oculellus and possibly an allopatric species, but more compressed. S. leei is also one of the few species of the genus in which an incipient side dimorphism of the otoliths could be observed. Distribution: Pacific cost of Columbia and Panama. Symphurus (Aphorista) atricaudus JORDAN & GILBERT 1880 Figs. 1005-1009 Investigated otoliths: 6 otoliths (3 left side and 3 right side) from southern California, ZMH Ot.4.7.1995.9-14 (leg. Fitch). Discussion: Rather thickset, high otoliths with a rather narrow sulcus and an extremely irregular outline. S. atricaudus is one of the species within this genus with a very wide range in morphological variations, in particular as the outline is concerned. Distribution: California, USA. Schwarzhans: Pleuronectiformes 365 1003 1004c 1004a 1004d 1004b 1005a 1006a 1005c 1006c 1005b 1006b 1007a 1007b 1008 1009 Figs. 1003-1004: Symphurus (Aphorista) leei JORDAN & BOLLMAN 1889 – 15 × Figs. 1005-1009: Symphurus (Aphorista) atricaudus JORDAN & GILBERT 1880 – 10 × Symphurus (Symphurus) williamsi JORDAN & CULVER 1895 Fig. 1010 Symphurus (Symphurus) atramentatus JORDAN & BOLLMAN 1889 Fig. 1011 Investigated otoliths: 1 otolith (right side), Tobago Isl., Pacific coast of Panama, BMNH 1926.7. 12.77-78. Investigated otoliths: 1 otolith (right side) from Lower California, BMNH 1930.9.2.38. Discussion: A roundish, rather thickset otolith with still a rather large sulcus. Discussion: Very similar to S. williamsi and probably a sympatric species, but may be somewhat more thin. Distribution: Pacific coast of Mexico, south to Panama. Distribution: Pacific coast of tropical America from Lower California to Colombia. Piscium Catalogus, Part Otolithi piscium, Vol. 2 366 1010a 1010c 1011c 1011a 1010d 1010b 1011b 1012 1013c 1013b 1013a 1013d 1015a 1014 1015b 1015c 1015d 1016 Fig. 1010: Symphurus (Symphurus) williamsi JORDAN & CULVER 1895 – 15 × Fig. 1011: Symphurus (Symphurus) atramentatus JORDAN & BOLLMAN 1889 – 10 × Figs. 1012-1013: Symphurus (Symphurus) orientalis (BLEEKER 1879) – 15 × Figs. 1014-1015: Symphurus (Symphurus) septemstriatus (ALCOCK 1891) – 15 × Fig. 1016: Symphurus (Symphurus) gilesi (ALCOCK 1889) – 15 × Symphurus (Symphurus) orientalis (BLEEKER 1879) Figs. 1012-1013 Symphurus (Symphurus) septemstriatus (ALCOCK 1891) Figs. 1014-1015 Investigated otoliths: 2 otoliths (left and right side) from off Kochi, Japan, ZMH Ot.4.7.1995.1516 (leg. Sasaki). Investigated otoliths: 2 otoliths (left and right side) from off Colombo, Ceylon, ZMH Ot.4.7.1995.17 (leg. BMNH 1928.3.20.72 and BMNH 1928.3.20.72. Discussion: Very thickset, regularly round otoliths with a small sulcus and a rather convex inner face. Discussion: Thickset, less well rounded and high otoliths with a very small sulcus and a flat inner face. Distribution: Japan. Distribution: Ceylon and Andaman Islands. Schwarzhans: Pleuronectiformes 367 1018a 1017 1018c 1018d 1018b 1020c 1019 1020b 1020a 1021 Figs. 1017-1021: Symphurus (Symphurus) nigrescens RAFINESQUE 1810 – 15 × Symphurus (Symphurus) gilesi (ALCOCK 1889) Fig. 1016 Investigated otoliths: 1 somewhat eroded otolith (left side), from the Gulf of Aden, BMNH 1939.5.24.1827-34. Discussion: Very similar to S. septemstriatus (also with flat inner face), but with rather shallow dorsal rim and an extremely small sulcus. Distribution: Gulf of Aden, Bay of Bengal, Kei Islands, lower shelf. Symphurus (Symphurus) nigrescens RAFINESQUE 1810 Figs. 1017-1021 syn. Plagusia lactea BONAPARTE 1833 syn. Plagusia picta COSTA 1862 Investigated otoliths: 5 otoliths (2 left and 3 right side), 3 otoliths (figs. 1017, 1018, 1021) from Bou Aioun, Algeria, ZMH Ot.4.7.1995.18-20 (leg. BMNH 1950.2.8.1-5), 2 otoliths (figs. 1019-1020) from the Bay of Biscay, ZMH Ot.4.7.1995.21 (leg. BMNH 90.6.16.46) and BMNH 90.6.16.46. Discussion: Roundish otoliths with a somewhat narrowed dorsal rim and a very small sulcus with rather regular outline, anteriorly pointed. Distribution: Mediterranean, East-Atlantic from France to Angola, in rather deep water. Piscium Catalogus, Part Otolithi piscium, Vol. 2 368 8. Selected literature Recent fishes (Includes major references which deal with Pleuronectiformes, regional faunal lists or publications which include figures of recent Pleuronectiform otoliths or other references of recent otoliths cited in the text) AMAOKA, K. (1969): Studies on the sinistral flounders found in the waters around Japan. Taxonomy, anatomy and phylogeny. – J. Shimonoseki Univ. Fish., 18: 65-340.  (1972): Osteology and relationships of the Citharid flatfish Brachypleura novaezeelandiae. – Japanese Journ. Ichthyol., 19: 263-273; Tokyo. BAUZA-RULLAN, J. (1958): Otolitos de peces actuales. – Bol. Roy. Soc. Espan. Hist. natur., 56: 111-126; Madrid. BLACHE, J., CADENAT, J. & STAUCH, A. (1970): Clés de détermination des poissons de mer signalés dans l’Atlantique oriental. – O.R.S.T.O.M., Paris: 1-479. BÖHLKE, J. E. & CHAPLIN, C. C. (1993): Fishes of the Bahamas and adjacent tropical waters. – Univ. Texas Press, Austin: 1-771. CHABANAUD, P. (1928): Revision des poissons Hétérosomes de la sous-famille des Achirinae, d’aprés les types de Kaup, de Günther et de Steindachner. – Bull. Inst. Oceanogr., 523: 1-53; Monaco.  (1930): Les genres de poissons Hétérosomates (Pisces Heterosomata) appartenant à la sous-famille des Soleinae. – Bull. Inst. Oceanogr., 555: 1-22; Monaco.  (1931): Sur divers poissons Soléiformes de la région Indo-Pacifique. – Bull. Soc. Zool. France, 56: 291-305; Paris.  (1934): Les Soléidés du groupe Zebrias, définition d’un sous-genre nouveau et description d’une sousespèce nouvelle. – Bull. Soc. Zool. France, 59: 420436; Paris.  (1938): Sur un très rare Achiridé du bassin de l’Amazone. – Bull. Soc. Zool. France, 63: 200-211; Paris.  (1939): Catalogue systématique et chorologique des Téléostéens dyssymétriques du globe. – Bull. Inst. Oceanogr., 763: 1-31; Monaco.  (1948): Morphologie et systématique des soléides affectés d’une atropie plus on moins complète de l’oeil migrateur. – Zool. Verhand., Rijksmus. Natuur. Hist. Leiden, 3: 1-58.  (1949): Le problème de la phylogenèse des Heterosomata. – Bull. Inst. Oceanogr., 950: 1-24; Monaco.  (1949): Contribution à l’anatomie et à la systématique de la famille des Bothidae, s.str. – Bull. Soc. Zool. France, 74: 246-253; Paris.  (1949): Téléostéens dissymétriques (Heterosomata).In: Résultats scientifiques des croisiéres du naviereécole Belge “Mercator”. – Mem. Inst. Roy. SWci. Natur. Belg., 33; Brussels.  (1955): Rectifications affèrentes à la nomenclature et à la systématique des Pleuronectiformes du sousordre des Soleoidei. – Bull. Mus. nat. Hist. natur., 27: 447-452; Paris.  (1956): Les Symphurus marbrés du complexe IndoPacifique tropical. – Arch. Mus. Nat. Hist. Natur., 7: 79-100; Paris. CHAINE, J. (1936): Recherches sur les otolithes des poissons, Etude descriptive et comparative de la sagitta des téléostéens; 3. – Act. Soc. Linnéenne Bordeaux, 88: 1-246, pl.I-XV. CHAPLEAU, F. (1987): Comparative osteology and intergeneric relationships of the tongue soles (Pisces; Pleuronectiformes; Cynoglossidae). – Can. J. Zool., 66: 1214-1232.  (1993): Pleuronectiform relationships: a cladistic reassessment. – Bull. Marine Sci., 52: 516-540; Coral Gables, Florida. CHAPLEAU, F. & KEAST, A. (1988): A phylogenetic reassessment of the monophyletic status of the family Soleidae, with notes on the suborder Soleoidei. – Can. J. Zool., 66: 2797-2810. CHIRICHIGNO, N. (1974): Clava para identificar los peces marinos del Peru. – Inst. del mar del Peru, 44: reprinted 1978, Otto Koeltz Verl.: 1-387; Koenigstein. DESOUTTER, M. (1990): Soleidae. In: Check list of the fishes of the Eastern Tropical Atlantic (QUERO, J. C., ed.). – UNESCO, 1037-1049; Paris.  (1994): Révision des genres Microchirus, Dicologlossa et Vanstraelenia (Pleuronectiformes, Soleidae). – Cybium, 18: 215-249; Paris. ESCHMEYER, W. N. (1990): Catalog of the genera of recent fishes. – California Acad. Sci., 1-697; San Francisco. EVSEENKO, S. A. (1984): A new genus and species of lefteye flounder, Pseudomancopsetta andriashevi, and their position in the suborder Pleuronectoidei. – Vop. Ikhtiol., 24: 709-717. FRASER, T. H. (1971): Notes on the biology and systematics of the flatfish genus Syacium (Bothidae) in the straits of Florida. – Bull. marine sci., Univ. Miami, Marine Lab., 21: 491-509; Coral Gables, Florida. FROST, E. A. (1930): A comparative study of the otoliths of the Neopterygian fishes; part XIII. – Ann. Mag. Nat. Hist., 10: 231-239; London. FUTCH, C. R. (1977): Larvae of Trichopsetta ventralis, with comments on the intergeneric relationships within the Bothide. – Bull. marine sci., Univ. Miami, Marine Lab., 27: 740-757; Coral Gables, Florida. GINSBURG, I. (1951): Western Atlantic tonguefishes with descriptions of six new species. – U.S. Fish & Wildlife Serv., 36: 185-201; Washington.  (1952): Flounders of the genus Paralichthys and related genera in American waters. – Fish. Bull Fish & Wildlife Serv., 52, Fishery Bull., 71: 267-351; Washington. Schwarzhans: Pleuronectiformes 369 GLOERFELT-TARP, T. & KAILOLA, P. J. (1984): Trawled fishes of southern Indonesia and northwestern Australia. – Tien Wah Press: 1- 406; Singapore. GOODE, G. B. & BEAN, T. H. (1883): Reports on the results of dredging, under the supervision of Alexander Agassiz, on the East coast of the United States, during the summer of 1880, by the U S Coast Survey steamer “Blake”, Commander J R Bartlett, U S N, commanding. – Bull. Mus. comp. Zool., 10: 183-226; Harvard. GON, O. & HEEMSTRA, P. C. (1990): Fishes of the southern ocean. – J.L.B. Smith Inst. Ichthyol., Grahamstown: 1-462. HENSLEY, D. A. (1977): Larval development of Engyophrys senta (Bothidae), with comments on intermuscular bones in flatfishes. – Bull. Mar. Sci., 27: 681703; Washington. HENSLEY, D. A. & AHLSTROM, E. H. (1984): Pleuronectiformes.- In: Ontogeny and systematics of fishes. – Amer. Soc. Ichthyol. Herpetol., Spec. Pub. 1: 670-687; Lawrence, Canada. HUBBS, C. L. (1945): Phylogenetic position of the Citharidae, a family of flatfishes. – Misc. Pub., Mus. Zool., Univ. Michigan, 23: 1-38; Ann Arbor. JAMES, G. D. (1972): Revision of the New Zealand flatfish genus Peltorhamphus with descriptions of two new species. – Copeia, 2: 345-355. JORDAN, D., EVERMANN, B. & CLARK, H. (1930): Check list of the fishes and fishlike vertebrates of North and Middle America north of the northern boundary of Venezuela and Columbia. – Reprinted 1955; Rep. United States Commissioner Fish., App. X: 1-670. KOTTHAUS, A. (1977): Fische des Indischen Ozeans. Ergebnisse der ichthyologischen Untersuchungen während der Expedition des Forschungsschiffes “Meteor” in den Indischen Ozean, Oktober 1964 bis Mai 1965; Teil XX: Pleuronectiformes (Heterosomata). – “Meteor” Forsch.-Ergebnisse, Reihe D, 26: 1-20; Berlin, Stuttgart. LAUDER, G. V. & LIEM, K. F. (1983): The evolution and interrelationships of the Actinopterygian fishes. – Bull. Mus. Comp. Zool., 150: 95-197; Cambridge, Mass. MASUDA, H., AMAOKA, K., ARAGA, C., UYENO, T. & YOSHIMO, T. (1984): The fishes of the Japanese Archipelago. – Tokai University Press; Tokio. MENON, A. G. (1977): A systematic monograph of the tongue soles of the genus Cynoglossus HamiltonBuchanan (Pisces: Cynoglossidae). – Smithsonian Contrib. Zool., 238: 1-129; Washington.  (1979): A revision of the fringed-lip tongue soles of the genus Paraplagusia Bleeker, 1865 (family Cynoglossidae). – Matsya, 5: 11-22; Madras. MENEZES, N. & BENVEGNU, G. de Q. (1976): On the species of the genus Symphurus from the Brazilian coast, with descriptions of two new species (Osteichthys, Pleuronectiformes, Cynoglossidae). – Pap. Avulsos Dept. Zool., 30: 137-170; Sao Paulo. Piscium Catalogus, Part Otolithi piscium, Vol. 2 MUNROE, T. A (1990): Eastern Atlantic tonguefishes (Symphurus: Cynoglossidae, Pleuronectiformes) with descriptions of two new species. – Bull. Marine. Sci., 47: 464-515; Coral Gables, Florida.  (1991): Western Atlantic tonguefishes of the Symphurus plagusia comples, with descriptions of two new species. – U.S. Fishery Bull., 89: 247-287; Washington. NELSON, J. P. (1984): Fishes of the world; 2nd edition. – John Wiley & sons, New York: 1-523.  (1994): Fishes of the world; 3rd edition. – John Wiley & sons, New York: 1-600. NIELSEN, J. (1961): Atlantide Report No. 6. Psettodoidea and Pleuronectoidea (Pisces, Heterosomata). – Danish Science Press, Copenhagen: 101-129.  (1961): Galathea Reports Vol. 4. Heterosomata (Pisces). – Dan. Sci. Press: 219-227; Copenhagen.  (1963): Atlantide Report No. 7. Soleoidea (Pisces, Heterosomata). – Danish Science Press, Copenhagen: 7-36.  (1963): Notes on some Heterosomata (Pisces) from N-W South America with the description of a new genus and species and a new subspecies of Paralichthinae. – Vidensk. Medd. fra Dansk naturh. Foren., 125: 377-405; Copenhagen.  (1963): Description of two large unmetamorphosed flatfish-larvae (Heterosomata). – Vidensk. Medd. fra Dansk naturh. Foren., 125: 401-407; Copenhagen.  (1964): Heterosomata (Pisces) collected by dr. Th. Mortensen off South Africa. – Vidensk, Medd. fra Dansk naturh. Foren., 127: 127-135; Copenhagen. NORMAN, J. R. (1934): A systematic monograph of the flatfishes (Heterosomata); Vol. 1: Psettodidae, Bothidae, Pleuronectidae. – The Trustees of the British Museum, London: 1-459  (1937): Coast fishes. Part II. The Patagonian region. – Discovery Reports, 16: 1-150.  (1939): The John Murray expedition 1933-34 scientific reports; vol. VII: zoology. – Brit. Mus. (Nat. Hist.): 1-116; London. OCHIAI, A. (1963): Soleina (Pisces). – Fauna Japonica; Biogeogr. Soc. Japan, Nat. Sci. Mus.: 1-114; Tokyo. OHE, F. (1985): Marine fish-otoliths of Japan. – Bull. Senior High School Aichi Univ. Educ., Spec. Vol., 1184; Hirosawa. PARKER, G. H. (1903): The optic chiasma in Teleosts and its bearing on the asymmetry of the Heterosomata (flatfishes). – Bull. Mus. Comp. Zool., 40: 221-242; Cambridge, Mass. PAULIN, C., STEWART, A., ROBERTS, C. & MC MILLAN, P. (1989): New Zealand fish. A complete guide. – Nat. Mus. N.Z. Misc. Ser. 19, Wellington. QUERO, J.-C., HENSLEY, D. A. & MAUGÉ, A. L. (1989): Pleuronectidae de l’ile de la Réunion et de Madagascar; II. Genres Samaris et Samariscus. – Cybium, 13: 105-114; Paris. REGAN, C. T. (1910): The origin and evolution of the teleostean fishes of the order Heterosomata. – Ann. Mag. Nat. Hist., 6: 484-496; London. 370 SAKAMOTO, K. (1984): Interrelationships of the family Pleuronectidae (Pisces: Pleuronectiformes). – Mem. Fac. Fish. Hokkaido Univ., 31: 95-215; Hokadate. SCHWARZAHNS, W. (1978): Otolith-morphology and its usage for higher systematical units, with special reference to the Myctophiformes s.l. – Meded. Werkgr. Tert. Kwart. Geol., 15: 167-185; Rotterdam.  (1993): A comparative morphological treatise of recent and fossil otoliths of the family Sciaenidae (Perciformes). – Verl. Dr. F. Pfeil, Piscium Catalogus, Otolithi Piscium, 1: 1-245; München.  (1994): Sexual and ontogenetic dimorphism in otoliths of the family Ophidiidae. – Cybium, 18: 71-98; Paris. SCOTT, T. D., GLOVER, C. J. & SOUTHCOTT, R. V. (1974): The marine and freshwater fishes of South Australia. – A.B.James Govn. Print.: 1-392; Adelaide. SHEN, S.-C. (1984): Coastal fishes of Taiwan. – Dept. Zool. Nat. Taiwan Univ., Taipei: 1-190. SMALE, M. J., WATSON, G. & HECHT, T. (1995): Otolith atlas of the southern African marine fishes. Ichthyological Monographs of the J. L. B. Smith Institute of Ichthyology, 1: 1-253, Grahamstown. SMITH, M. M. & HEEMSTRA, P. C. (1986; ed.): Smith’s sea fishes. – Springer Verl., Berlin: 1-1047. STAUCH, A. & BLANC, M. (1964): Dageichthys lakdonensis, Téléostéen pleuronectiforme du bassin de la Haute-Bénoué. – Bull. Mus. Nat. Hist. Natur., 36: 172-177, Paris. TOPP, R. W. & HOFF, F. H. (1972): Memoirs of the Hourglass cruises; flatfishes (Pleuronectiformes). – Marine Res. Lab. Florida Dept. Natur. Resources, St. Petersburg, Florida, vol. IV, part II: 1-135. TORCHIO, M. (1973): Soleidae. In: Check list of the fishes of the northeastern Atlantic and the Mediterranean (HUREAU, J. C. & MONOD, T., eds.). – UNESCO: 628-634; Paris. WEBER, M. & DE BEAUFORT, L. F. (1929): Fishes of the Indo-Australian Archipelago. Vol. 5. – Brill, Leiden. WHITEHEAD, P. J., BAUCHOT, M.-L., HUREAU, J.C., NIELSEN, J. & TORTONESE, E. (1986): Fishes of the North-eastern Atlantic and the Mediterranean; Vol. III. – UNESCO, Paris: 1015-1473. WHITLEY, G. P. (1968): A check-list of the fishes recorded from the New Zealand region. – The Australian Zoologist, 15: 1-102; Sydney. Fossil fishes (Includes references of fossil pleuronectiform otoliths and other fossil otoliths cited in the text) ANDREWS, S. M., GARDINER, B. G., MILES, R. S. & PATTERSON, C. (1967): Pisces. In: The fossil record. – Geol. Soc. London, 637-683. ANFOSSI, G. & MOSNA, S. (1979): La fauna ittiologica di Monte Roero (Alba, Italia NW), Otoliti. – Atti. Ist. Geol. Univ. Pavia, 27: 111-132; Pavia. BASSOLI, G. (1906): Otoliti fossili terziari dell’ Emilia. – Riv. Ital. Paleontol., 12: 36-58; Perugia. BAUZA-RULLAN, J. (1955): Contribucion al conocimiento de la fauna ictiologica fosil de Espana. – Bol. Soc. Hist. natur. Baleares, 1: 71-80; Palma de Mallorca. CHANET, B. & SCHULTZ, O. (1994): Pleuronectiform fishes from the Upper Badenian (Middle Miocene) of St. Margarethen (Austria). - Ann. Naturhist. Mus. Wien, 96A: 95-115; Wien. DANTE, J. & FRIZZELL, D. (1965): Otoliths of some early cenozoic fishes of the Gulf Coast. – J. Paleontol., 39: 687-718. FITCH, J. (1964): The fish fauna of the Playa Rey loacality, a southern California marine Pleistocene deposit. – Los Angeles County Mus. Contrib. Sci., 82: 3-35; Los Angeles.  (1966): Additional fish remains, mostly otoliths, from a Pleistocene deposit at Playa del Rey, California. – Los Angeles County Mus. Contrib. Sci., 119: 1-16; Los Angeles.  (1967): The marine fish fauna, based primarily on otoliths of a Lower Pleistocene deposit at San Pedro, California (LACMIP 332, San Pedro Sand). – Los Angeles County Mus. Contrib. Sci., 128: 1-23; Los Angeles.  (1968): Otoliths and other fish remains from the Timms Point Silt (Early Pleistocene) at San Pedro, California. – Los Angeles County Mus. Contrib. Sci., 146: 1-29; Los Angeles.  (1970): Fish remains, mostly otoliths and teeth, from the Palos Verdes Sand (Late Pleistocene) of California. – Los Angeles County Mus. Contrib. Sci., 199: 1-41; Los Angeles. FITCH, J. & LAVENBERG, R. (1981): Teleost fish otoliths from Lee Creek Mine, Aurora, North Carolina (Yorktown Formation: Pliocene). – Smithsonian Contrib. Paleobiol., 53: 509-529; Washington. FITCH, J: & REIMER, R. (1967): Otoliths and other fish remains from a Long Beach, California, Pliocene deposit. – Bull. S. California Acad. Sci., 66: 77-91; Los Angeles. FROST, E. A. (1925): Description of fish otoliths from the Tertiary formations of Atcheen, North Sumatra. – Dienst Mijnb. Nederl. Oost-Indie, Weten. Meded., 2: 1-28; Weltevreden.  (1934): Otoliths of fishes from the Lower Tertiary formations of Southern England. Part V: Anacan- Schwarzhans: Pleuronectiformes 371 thini, Heterosomata, Ostariophysi. – Ann. Mag. nat. Hist., 14: 500-505; London. GAEMERS, P. A. M. (1972): Otoliths from the type locality of the Sands of Berg (Middle Oligocene) at Berg, Belgium. – Meded. Werkgr. Tert. Kwart. Geol., 9: 73-85; Leiden.  (1974): Otolieten uit het Merksemien en Icenien van Boring Ouwerkerk (Zeeland, Nederland). – Meded. Werkgr. Tert. Kwart. Geol., 11: 133-143; Leiden. GAEMERS, P. A. M. & SCHWARZHANS, W. (1973): Fisch-Otolithen aus dem Pliozän von Antwerpen (Belgien) und Ouwerkerk (Niederlande) und aus dem Plio-Pleistozän der Westerschelde (Niederlande). – Leidse Geol. Meded., 49: 207-257; Leiden.  &  (1982): Fisch-Otolithen aus der Typuslokalität der obermiozänen Sylt-Stufe (Morsum-Kliff, Insel Sylt, Nordwestdeutschland). – Leidse Geol. Meded., 52: 119-177; Leiden. GRENFELL, H. (1984): Early Miocene teleost otoliths from Parengarenga Harbour, New Zealand. – NZ J. Geol. Geophys., 27: 51-96; Wellington. HATAI, K. (1965): Some Pliocene fish otoliths from Japan. – Senckenbergiana lethaea, 46a: 133-143; Frankfurt/M. HEINRICH, W.-D. (1968): Fischotolithen aus dem Obermiozän von Hohen Woos. – Z. Gesamtgeb. geol. Wiss., 18: 1-111; Berlin.  (1970): Nachweis der Teleosteergattung Lepidorhombus Günther, 1862 im Chatt von Malliß. – Geologie, 19: 883-887; Berlin. JONET, S. (1973): Etude des otolithes des téléostéens (pisces) du Miocène des environs de Lisbonne. – Communic. Serv. geol. Port., 56: 107-294; Lisboa. KOKEN, E, (1884): Über Fisch-Otolithen, insbesondere über diejenigen der nord-deutschen Oligozän-Ablagerungen. – Z. deutsch. geol. Ges., 36: 500-565; Berlin.  (1891): Neue Untersuchungen an tertiären Fischotolithen, II. – Z. deutsch. geol. Ges., 43: 77-170; Berlin. LANCKNEUS, J. & NOLF, D. (1979): Les otolithes des téléostéens redoniens de Bretagne (Néogène de l’Ouest de la France). – Bull. Inst. geol. Bassin Aquitaine, 25: 83-109. LIEBUS, A. (1927): Neue Beiträge zur Kenntnis der Eozänfauna des Krappfeldes in Kärnten. – Jahrb. geol. Bundesanst., 77: 333-393; Wien. MENZEL, H. (1986):Otolithen aus dem Oligozän und Miozän von Nordwestdeutschland (zwischen ElbeWeser-Aller). In: Nordwestdeutschland im Tertiär. – Beitr. Reg. Geol. Erde, 18: 446-502; Stuttgart. MÜLLER, A. (1995, ms): Die Ichthyofauna des Oberoligozäns der Hessischen Senke (Raum Kassel, Bundesrepublik Deutschland). – Senckenberg Courrier, Frankfurt/M. NOLF, D. (1972): Deuxième note sur les téléostéens des sables de Lede (Éocène Belge). – Bull. Soc. belge. Géol., Paléont., Hydrol., 81: 95-109; Bruxelles.  (1972): Sur la faune ichthyologique des formations du Panisel et de den Horn (Éocène Belge). – Bull. Piscium Catalogus, Part Otolithi piscium, Vol. 2 Soc. belge Géol., Paléont., Hydrol., 81: 111-138; Bruxelles.  (1972): Les otolithes du Calcaire Grossier à Fercourt (Éocène du bassin de Paris). – Bull. Soc. belge Géol., Paléont., Hydrol., 81: 139-157.  (1976): Les otolithes des téléostéens de l’Oligo-Miocène belge. – Ann. Soc. roy. Zool. Belg., 106: 3-119; Bruxelles.  (1976): Les otolithes des téléostéens néogènes de Trinidad. – Eclogae Geol. Helv., 69: 703-742; Basel.  (1978): Les otolithes des téléostéens du Plio-Pleistocène belge. – Geobios, 2: 517-559; Lyon.  (1981): Révision des types d’otolithes de poissons fossiles décrits par R. Schubert. – Verh. Geol. B.-A., 133-183; Wien.  (1985): Otolithi Piscium. – Handbook of Paleoichthyology, 10: 1-145; Gustav Fischer Verl., Stuttgart.  (1988): Les otolithes de téléostéens éocènes d’Aquitaine et leur intérèt stratigraphique. – Acad. roy. Belg., Mem. Cl. Sci., 19: 1-147. NOLF, D. & BAJPAI, S. (1992): Marine Middle Eocene fish otoliths from India and Java. – Bull. Inst. roy. Sci. natur. Belg., 62: 195-221; Bruxelles. NOLF, D. & CAPPETTA, H. (1976): Observations nouvelles sur les otolithes des téléostéens du Calcaire Grossier (Éocène du bassin de Paris). – Geobios, 9: 251-277; Lyon.  &  (1980): Les otolithes de téléostéens du Miocène de Montpeyroux (Hérault, France). – Palaeovertebrata, 10: 1-28; Montpellier.  &  (1988): Otolithes de poissons pliocènes du Sud-Est de la France. – Bull. Inst. roy. Sci. natur. Belg., 58: 209-271; Bruxelles. NOLF, D. & LAPIERRE, H. (1979): Otolithes de poissons nouveaux ou peu connus du Calcier Grossier et de la formation d’Auvers (Éocène du bassin parisien). – Bull. Mus. natn. Hist. natur., 4: 79-125; Paris. NOLF, D. & MARTINELL, J. (1980): Otolithes de téléostéens du Pliocène des environs de Figueras (Catalogne). – Geologica et Palaeontologica, 14: 209234; Marburg. NOLF, D. & SMITH, R. (1983): Les otolithes de téléostéens du stratotype des sables d’Edegem (Miocène inferieur de la Belgique). – Bull. Soc. belg. Geol., 92: 89-98; Bruxelles. NOLF, D. & STEURBAUT, E. (1983): Revision des otolithes de téléostéens du Tortonien stratotypique et de Montegibbio (Miocène superieur d’Italie septentrionale). – Meded. Werkgr. Tert. Kwart. Geol., 20: 143-197; Leiden. NOLF, D. & STRINGER, G. L. (1992): Neogene paleontology in the northern Dominican Republic. 14: Otoliths of teleostean fishes. – Bull. Amer. Paleont., 102: 41-81; New York. OHE, F. (1981): Fish-otoliths from the Dainichi sand and the Fosoya tuffaceous members of the Pliocene Kakegawa Group, Shizuoka Prefecture, Central Japan. – Bull. Senior High School Aichi Univ. Educ., 8: 125-194; Hirosawa. 372  (1983): On the otoliths of deep water fishes from Pliocene Hijikata mud formation exposed in the Southern part of Kakegawa City, Shizuoka Prefecture, Central Japan. – Bull. Senior High School Aichi Univ. Educ., 10: 1-54; Hirosawa. POBEDINA, W. M. (1954): Iskopajenije otolity ryb miozenowyx otlozhenij Aserbajdzhana i ich stratigraficheskoye znachenie. – Iswest. Akad. Asebajdzhansk. SSSR, 23-37. POSTHUMUS, O. (1929): Vischotolieten van NO-Borneo. – Dienst. Mijnb. Nederland.-Indie Weten. Meded., 9: 87-108; Bandung. PRIEM, F. (1914): Sur des otolithes des poissons fossiles des terrains tertiaires du Sud-Ouest de la France. – Bull. Soc. geol. France, 14: 244-278; Paris. RADWANSKA, U. (1984): Some new fish otoliths from the Korytnica Clays (Middle Miocene; Holy Cross Mountains, Central Poland). – Acta Geol. Polon., 34: 299-322; Warszawa.  (1992): Fish otoliths in the Middle Miocene (Badenian) deposits of southern Poland. – Acta Geol. Polon., 42: 141-328; Warszawa. REICHENBACHER, B. (1988): Die Fischfauna der Kirchberger Schichten (Unter-Miozän) an der Typuslokalität Illerkirchberg bei Ulm. – Stuttgarter Beitr. Naturkde., 139: 1-53; Stuttgart. SANZ ECHEVERRIA, J. (1950):Otolitos fosiles del terciario de Mallorca. – Inst. Invest. geol. “Lucas Malleda”, 435-451; Madrid. SCHWARZHANS, W. (1973): Einige Otolithen aus dem Unteroligozän von Hückelhoven unter besonderer Berücksichtigung der Evolution der Trachinidae. – Meded. Werkgr. Tert. Kwart. Geol., 10: 31-43; Leiden.  (1974): Die Otolithen-Fauna des Chatt A und B (Oberoligozän, Tertiär) vom Niederrhein, unter Einbeziehung weiterer Fundstellen. – Decheniana, 126: 91-132; Bonn.  (1977): Otolithen aus dem Unteroligozän (Tertiär) von Hückelhoven (Kreis Heinsberg, NordrheinWestfalen). – Decheniana, 130: 268-292; Bonn.  (1978): Otolithen aus dem Unter-Pliozän von SüdSizilien und aus der Toscana. – Berliner geowiss. Abh. (A), 8: 1-52; Berlin.  (1980): Die tertiäre Teleosteer-Fauna Neuseelands, rekonstruiert anhand von Otolithen. – Berliner geowiss. Abh. (A), 26: 1-211; Berlin. – [1984: Fish otoliths from the New Zealand Tertiary (english translation). – Rep. N. Z. G. S., 113: 1-269; Lower Hutt]  (1981): Die Entwicklung der Familie Pterothrissidae (Elopomorpha; Pisces), rekonstruiert nach Otolithen. – Senckenbergiana lethaea, 62: 77-91; Frankfurt/M.  (1985): Tertiäre Otolithen aus South-Australia und Victoria (Australien). – Palaeo Ichthyologica, 3: 1-60; München.  (1986): Die Otolithen des Unter-Pliozän von Le Puget, S-Frankreich. – Senckenbergiana lethaea, 67: 219-273; Frankfurt/M.  (1994): Die Fisch-Otolithen aus dem Oberoligozän der Niederrheinischen Bucht. Systematik, Palökologie, Paläobiogeographie, Biostratigraphie und Otolithen-Zonierung. – Geol. Jahrb. (A), 140: 3-248; Hannover.  (in prep.): Die Otolithen aus der Oberkreide des Gerhartsreiter Grabens, Oberbayern. – Palaeo Ichthyologica; München. SCHUBERT, R. J. (1906): Die Fischotolithen des österreichisch-ungarischen Tertiärs. – Jahrb. geol. Reichsanst., 56: 623-706; Wien. SMIGIELSKA, T. (1973): Fish otoliths from the Lower Tortonian deposits at Niskowa near Nowy Sacz. – Roczn. P. T. Geol. (Ann. Soc. Geol. Pologne), 43: 1-40; Krakow. STEURBAUT, E. (1979): Les otolithes de téléostéens des Marnes de Saubriges (Miocène d’Aquitaine méridionale, France). – Palaeontographica (A), 166: 50-91; Stuttgart.  (1984): Les otolithes de téléostéens de l’Oligo-Miocène d’Aquitaine (Sud-Ouest de la France). – Palaeontographica (A), 186: 1-162; Stuttgart. STEURBAUT, E. & JONET, S. (1981): Révision des otolithes de téléostéens du Miocène portugais. – Bull. Soc. belge Géol., 90: 191-229; Bruxelles. STINTON, F. (1966): Fish otoliths from the London Clay. – Brit. Mus. natur. Hist., 404-478; London. SUZIN, A. V. (1942): Otolity ryb miocenovykh otloshenie Severnovo Kavkaza i Kerchenkovo. – Fond AsNIN DN & Fond GrosNIN. VORSTMANN, A. G. (1927): Tertiaire Vischotolieten van Java. – Dienst. Mijnb. Nederland.-Indie Weten. Meded.; 5: 1-16; Weltevreden. WEILER, W. (1942): Die Otolithen des rheinischen und nordwestdeutschen Tertiärs. – Abh. Reichsamt Bodenforsch., 206: 1-140; Berlin.  (1955): Untersuchungen an der Fischfauna von Unter- und Ober-Kirchberg bei Ulm, vornehmlich an Hand von Otolithen in situ. – Palaeontol. Z., 29: 88-102; Stuttgart.  (1958): Fisch-Otolithen aus dem Ober-Oligozän und dem Mittel-Miozän der Niederrheinischen Bucht. – Fortschr. Geol. Rheinland u. Westfalen, 1: 323-361; Krefeld.  (1959): Miozäne Fisch-Otolithen aus der Bohrung S. Pablo 2 im Becken von Veracruz in Mexiko. – N. Jahrb. Geol. Palaeontol., 109: 147-172; Stuttgart.  (1962): Fisch-Otolithen aus dem oberen Mittelmiozän von Twistringen Bez. Bremen. – Geol. Jahrb., 80: 277-294; Hannover. WEINFURTER, E. (1952): Die Otolithen aus dem Torton (Miozän) von Mühldorf in Kärnten. – Sitz.-Ber. österr. Akad. Wiss., math.-natur. Kl., 161: 149-172; Wien.  (1952): Die Otolithen der Wetzelsdorfer Schichten und des Florianer Tegels (Miozän, Steiermark). – Sitz.-Ber. österr. Akad. Wiss., math.-natur. Kl., 161: 455-498; Wien. Schwarzhans: Pleuronectiformes 373 Index References to valid taxa and main discussion of valid taxa are in bold. References to taxa from synonymy listings regarded as invalid are only presented from their individual entries – synonymized genera without type-species; synonymized species only under the species headings. References to figures are in bold and denoted with an asterisk (*). A abbotti, Citharichthys 147 abbreviatus, Cynoglossus 342, 348, 349* abentoni, Cynoglossus 347 abnormis, Aseraggodes 325 acadianus, Glyptocephalus 225 Acanthopsetta 210, 214, 218, 219, 220 nadeshnyi 219, 219* Acedia 360 Achiroides 311 Achiropsetta 104, 208, 210 tricholepis 210 Achiropsis 269, 279, 280 nattereri 280 Achirus 8, 22, 35, 36, 269, 270, 271, 272, 276 achirus 272, 273, 273*, 276 barnharti 273 declivis 273, 274* † fordycei 15, 337 garmani 273, 275, 275*, 276 klunzingeri 273 lineatus 273 lorentzi 273 mazatlanus 273, 274, 275* novae 273 opercularis 273 scutum 273, 274, 275* trichospilus 273 zebrinus 273 achirus, Achirus 272, 273, 273*, 276 Achlyopa 312 achne, Microstomus 246 acinaceus, Cynoglossus 352 aculeatus, Rhombus 91 acuminata, Plagusia 348 † acuminatus, (Pleuronectidarum) 15 acutirostris, Cynoglossus 342 Adamasoma 252 adspersus, Ammotretis 69 adspersus, Paralichthys 46*, 116, 117, 121, 121* aegyptiaca, Solea 297, 298, 301* Aesopia 269, 316 cornuta 316, 317, 317* † granum 16, 317 aestuarius, Paralichthys 116 aethalion, Citharichthys 136 affinis, Pseudorhombus 131 Alaeops 265 albiguttata, Paralichthys 107, 116, 117, 118*, 119 albomaculata, Poecilopsetta 266*, 267 albomaculata, Synaptura 308*, 309 Piscium Catalogus, Part Otolithi piscium, Vol. 2 albomarginata, Poecilopsetta 267 algoensis, Paralichthodes 62, 64, 65, 65* † alta, Paraplagusia 15, 356 altipinnis, Zebrias 321, 321* † altus, Cynoglossus 15, 356 † altus, Rhinoplagusia 356 † altus, Rhombus 15, 17, 26 amaokai, Parabothus 162 Amate 332 amblybregmatus, Orthopsetta 149 americanus, Hippoglossus 213 americanus, Pseudopleuronectes 238, 239* Ammopleurops 360 Ammotretis 27, 28, 29, 35, 40, 44, 45, 62, 65, 66, 68, 70 brevipinnis 69 elongatus 69, 69* macrolepis 69 rostratus 68, 69, 69* tudori 69, 69* annadalei, Zebrias 321 Anathyridium 272 andersoni, Pseudorhombus 129 andriashevi, Mancopsetta 209 Ancylopsetta 38, 104, 106, 108, 115 antillarum 106, 108, 109* cycloidea 106, 107, 108* dendritica 107 dilecta 107, 108, 108* kumperae 107 microtenus 107, 108, 108* quadrocellata 106, 107, 107* andrewsi, Arnoglossus 168 † angulata, Solea 15, 17 angulosa, Solea 295 † angulosus, Lepidorhombus 15, 20, 24, 95, 96, 97, 98*, 99 angustirostris, Limanda 238 † angustus, Citharopsettodes 15, 77 † angustus, Paracitharus 11, 15, 20, 25, 77, 78, 79*, Anisochirus 269, 310, 314, 316 panoides 312, 314, 316* annamensis, Pseudorhombus 132 annectens, Coccolus 159 annectens, Pseudaustroglossus 306 annularis, Brachirus 312 annulatus, Pseudorhombus 125, 130, 130*, 133 anomalus, Pseudorhombus 131 antarctica, Mancopsetta 209 Anticitharus 166 antillarum, Ancylopsetta 106, 108, 109* antillarum, Monolene 197, 198* † antiqua, Solea 286 †aomoriensis, Limanda 15, 17 374 Aphorista 360 Apionichthys 35, 52, 269, 279 dumerili 280, 280* apoda, Pleuronectes 271 † approximata, Solea 15, 23, 24, 285, 286, 288, 290 † approximatum, Buglossidium 285, 288 Apsetta 252 Apterygopectus 208 aquosus, Scophthalmus 91, 92, 93* arabicus, Arnoglossus 168 arabicus, Symphurus 362 Araias 228 aramaca, Pleuronectes 137 aramaca, Rhombus 119 Aramaca 135 arawak, Symphurus 362 arctifrons, Orthopsetta 149, 151, 152* arel, Cynoglossus 342, 351, 351*, 352, 353 Arelia 340 Areliscus 340 arenaceus, Citharichthys 147 arenicola, Engyprosopon 202 argus, Pleuronectes 159, 160 argus, Pseudorhombus 125, 132*, 133 ariommus, Araias 230 armstrongi, Arnoglossus 168 † arnoglossoides, Caulopsetta 15, 21, 27, 183, 184* arnoglossus, Pleuronectes 168 Arnoglossus 11, 12, 24, 45, 51, 52, 104, 105, 165, 166, 182, 183, 184, 186, 193 andrewsi 168 arabicus 168 armstrongi 168 aspilos 168, 176*, 177 bassensis 168 † bauzai 15, 25, 172 capensis 167, 168, 171*, 175, 183 dalgleishi 167, 168, 181, 182* debilis 168, 181, 181* elongatus 168 † extremus 15, 20, 27, 168, 178, 178* fisoni 168 † grenfelli 16, 20, 27, 168, 180, 180* grohmanni 168, 170, 171* † holleri 16, 20, 24, 25, 168, 170, 172, 173*, 286 imperialis 18, 20, 24, 167, 168, 169, 170, 171* † inconspectus 16, 172 japonicus 168 † kokeni 15, 16, 18, 20, 25, 26, 168, 170, 172, 174*, 175 kotthausi 168 † lapierrei 16, 20, 23, 168, 177, 177*, 178 laterna 14, 18, 20, 24, 27, 122, 166, 167, 168, 168*, 169, 170, 172, 174, 175, 181 † longus 16, 20, 27, 52, 167, 168, 178, 179*, 184 macrostoma 168, 169, 169* maculipinnis 168 marisrubri 168 † miocenicus 16, 170, 172 muelleri 168 multirastris 168 † novus 16, 20, 27, 52, 167, 168, 179, 180*, 184 oxyrhynchus 168 polyspilus 168 † prudhommae 16, 20, 24, 168, 177*, 178 † quadratus 16, 21, 26, 167, 168, 170, 174, 175* rueppelli 10, 167, 168, 176, 176*, 177 sayaensis 168 tapeinosoma 167, 168, 176, 176*, 177 † taureri 16, 17, 18, 21, 24, 25, 168, 170, 172, 173* tenuis 168 thori 168, 169, 171* waitei 168, 176*, 177 arsius, Pseudorhombus 124, 125, 127, 129, 129*, 134 asaedae, Monolene 197 asanoi, Samariscus 261 Aseraggodes 8, 269, 323, 324, 326 abnormis 325 bahamondi 325 beauforti 325 cyaneus 325, 326, 326* dubius 325 filiger 325, 326, 327* guttulatus 324, 325 haackeanus 325 herrei 325 kaianus 325 klunzingeri 325, 326, 327* kobensis 325, 325*, 326 macleayanus 325, 326, 327* melanostictus 325 microlepidotus 325 normani 325 ocellatus 325 persimilis 325 sinusarabici 325 smithi 325 texturatus 325 whitakeri 325 aspera, Limanda 227, 228, 229* asperrimum, Clidoderma 18, 21, 27, 245, 245* aspilos, Arnoglossus 168, 176*, 177 aspilos, Heterobuglossus 310, 311* asphyxiatus, Pnictes 280 asprella, Limanda 228 assimilis, Bothus 158 Asterorhombus 104, 166, 168, 199, 200 fijiensis 200, 201 intermedius 166, 200, 201, 201* Atherestes 210, 214, 215, 223 evermanni 215, 216* stomias 19, 21, 215, 216* atlanticus, Bothus 159 atlanticus, Citharichthys 154 atlanticus, Monochirus 290 atramentatus, Symphurus 362, 365, 366* atricaudus, Symphurus 18, 22, 52, 361, 362, 364, 364* atrimana, Monolene 197 attenuatus, Cynoglossus 341, 342 aurantiaca, Solea 300 aureus, Citharichthys 159 aurolimbata, Plagusia 356 australis, Microchirus 283 australis, Rhinoplagusia 349 australis, Symphurus 362 austrinus, Achirus 271 Austroglossus 269, 297, 306 Schwarzhans: Pleuronectiformes 375 microlepis 306, 307 pectoralis 306, 307, 307* avilesi, Apterygopectus 209 † awamoaensis, Grammatobothus 15, 20, 27, 163, 164, 165* axillaris, Brachypleurops 79 ayresii, Parophrys 250 Azevia 141 azevia, Solea 293 Azygopus 34, 35, 40, 65, 210, 211, 254, 263 pinnifasciatus 263, 264, 264* B bahamondi, Aseraggodes 325 bahianus, Rhombus 159 Baiostoma 272 † balangoensis, Solea 15, 17 † balearicus, Citharus 15, 18, 20, 25, 26, 72, 75, 75*, 76 balteata, Platessa 129 baltica, Pluronectes 235 barbatus, Rhombus 91 Barbourichthys 311 barnardi, Coryphaesopia 317 Barnardichthys 296 barnharti, Achirus 273 † bartonensis, Solea 15 Bascanius 166, 360 bassensis, Arnoglossus 168 bassensis, Rhombosolea 69 † bassolii, Phrynorhombus 15, 102 bathybius, Embassichthys 246 Bathysolea 10, 35, 269, 280, 281, 302, 304 lactea 305, 306 † polonica 16, 21, 25, 305*, 306 profundicola 305, 305*, 306 † bauzai, Arnoglossus 15, 25, 172 † bavayi, Psettodes 15, 19, 23, 58, 61, 62*, 64 beani, Poecilopsetta 266*, 267 Beaufortella 324 beauforti, Aseraggodes 325 belcheri, Psettodes 58, 59* † belgicus, Citharus 83 † belgicus, Eucitharus 15, 82 bellonaensis, Engyprosopon 202 bengalensis, Plagusia 358 bennettii, Psettodes 58 bergi, Symphurus 362 † biaculeatus, (Bothidarum) 15 † biaculeatus, Rhombocitharus 15, 20, 23, 81 Bibronia 360 bicolorata, Marleyella 55, 264, 265* bicoloratus, Kareius 236, 239* bicyclophorus, Paralichthys 116 bilineata, Lepidopsetta 240, 240*, 241 bilineata, Paraplagusia 18 bilineatus, Achirus 344 bilineatus, Cynoglossus 18, 22, 27, 342, 344, 348, 350*, 351 blachei, Arnoglossus 170 bleekeri, Apionichthys 280 bleekeri, Bothus 158 bleekeri, Engyprosopon 202, 203, 203* bleekeri, Solea 297, 298 blochi, Cynoglossus 342, 350*, 351 Piscium Catalogus, Part Otolithi piscium, Vol. 2 † boerialensis, Pleuronectes 15 bogdanovi, Pleuronectes 236 bollmani, Hippoglossina 110 boops, Caulopsetta 183 Boopsetta 265 borbonica, Solea 318 borealis, Pleuronectes 235 borneensis, Cynoglossus 342, 344, 345* borneensis, Engyprosopon 202 boscanion, Microchirus 281, 282, 283, 284* boscii, Lepidorhombus 10, 18, 94, 95, 95* (Bothidarum) † biaculeatus 15, 16 † dorsolobatus 15 † heletroides 16 † lapierrei 16, 177 † obliquus 16 † rhomboides 17 † weileri 17 Bothus 8, 11, 24, 44, 45, 51, 56, 104, 157, 162, 200 assimilis 158 bleekeri 158 constellatus 158, 159, 160* † contortus 15, 17 † decipiens 15, 17 ellipticus 158 guibei 158 leopardinus 158, 160 lunatus 158, 160, 160* mancus 158, 161, 161* melissi 158 myriaster 158, 161, 161* ocellatus 158, 159, 160* ovalis 158, 161 pantherinus 158, 159, 159*, 160 podas 157, 158, 159, 159*, 160 robinsi 158 † rosenthalensis 17 † semen 17 tricirrhatus 158 ypsigrammus 158 Bowenia 252 Brachirus 8, 35, 36, 269, 310, 311, 314, 323 annularis 312 breviceps 312 cinerascens 312, 314, 315* melanorhynchus 312, 314, 315* niger 312, 313, 313* orientalis 311, 312, 313*, 314 pan 312, 314, 315* salinarum 312 selheimi 312 villosa 312 zanzibarica 312 brachycephalus, Cynoglossus 353 Brachypleura 12, 34, 37, 38, 42, 44, 64, 71, 84, 85, 86, 210 novaezeelandiae 86, 87, 87*, 226 † pentagonalis 16, 20, 24, 86, 87, 88, 88* † xenosulcis 17, 20, 26, 86, 87, 88, 89* Brachypleurops 79 Brachyprosopon 246 brachyrhynchus, Plagusia 356 brasiliensis, Paralichthys 116, 119, 119*, 121 376 brasiliensis, Xystreurys 112 breviceps, Brachirus 312 brevipinnis, Ammotretis 69 brevirictis, Psettina 186, 187* brevirostris, Cynoglossus 358 brevirostris, Plagusia 348 brevis, Cynoglossus 356 broadhursti, Cynoglossus 342, 355, 357* browni, Cynoglossus 342 browni, Solea 271 brunneus, Cynoglossus 352 buchanani, Cynoglossus 358 Buglossidium 281, 282 † approximatum 285, 288 † frequens 15, 285, 286, 288 luteum 19, 281 Buglossus 281 C cacatuae, Arnoglossus 259 cadenati,Cynoglossus 342 cadenati, Synaptura 308 caeca, Cryptops 323 caeruleosticta, Paralichthys 116 californicus, Paralichthys 18, 20, 114, 115, 116, 120, 120*, 121, 122 calimanda, Pleuronectes 103 callopterus, Symphurus 362 canariensis, Cynoglossus 342, 343, 343*, 344 cancellatus, Zebrias 321, 322, 322* candidissimus, Rhombus 159 cantori, Trulla 344 Cantoria 340 cantoris, Plagusia 351 capellonis, Solea 301 capensis, Arnoglossus 167, 168, 171*, 175, 183 capensis, Cynoglossus 342 capensis, Heteromycteris 332, 333* caribbaea, Trichopsetta 190 caribbeanus, Symphurus 362 carnaria, Platessa 236 carpentari, Cynoglossus 342, 359, 361* cartwrighti, Pseudorhombus 129 Catathyridium 269, 270, 273, 275 grandiviri 276 jenynsi 275, 276, 276* Caulopsetta 104, 165, 168, 176, 182 † arnoglossoides 15, 21, 27, 183, 184* boops 183 scapha 182, 183, 183*, 184 † cauneillensis, Citharus 15, 83 † cauneillensis, Rhombocitharus 15, 20, 23, 81, 83, 83* cayennensis, Citharichthys 147 Cephalopsetta 38, 104, 124, 135 ventrocellatus 135 ceratophrys, Arelia 358 Chabanaudetta 314 chabanaudi, Symphurus 362*, 363 Chaenopsetta 114, 115 chartes, Platotichthys 160 Charybdia 166 Chascanopsetta 10, 34, 44, 45, 48, 49, 104, 105, 206, 207, 208 galathaea 207 lugubris 19, 27, 46*, 135, 207, 207* megagnatha 207 micrognathus 207 microstoma 207 prognathus 207 prorigera 207 cheni, Heteromycteris 332 chirophthalma, Vanstraelenia 303, 304, 304* chittendeni, Cyclopsetta 141, 142*, 143 chlorospilus, Parabothus 162, 162* Chopinopsetta 71 chui, Nematops 269 cicatricosus, Pleuronectes 231 ciliaris, Engyophrys 191 cinerascens, Brachirus 312, 314, 315* cinnamoneus, Pseudorhombus 125, 126, 126* † circularis, Eucitharus 15 circularis, Platophrys 161 † circularis, Rhombocitharus 15, 20, 23, 81, 83 Citharichthys 11, 34, 38, 42, 44, 52, 104, 145, 148, 149, 154, 156 abbotti 147 arenaceus 147 gilberti 147, 147* macrops 147, 148, 148* platophrys 147 sordidus 19 spilopterus 145, 146*, 147 stampfli 146*, 147 stigmaeus 19 uhleri 147 † varians 17 xanthostigma 19 Citharoides 11, 37, 70, 71, 72, 79 macrolepidotus 79, 80* † Citharopsettodes 13, 70, 77 † angustus 15, 77 Citharus 11, 70, 71, 72, 77 † balearicus 15, 18, 19, 25, 26, 72, 75, 75*, 76 † cauneillensis 15 † latisulcatus 16 linguatula 18, 71, 72, 73*, 74, 75, 82 † lusitanicus 16, 17, 19, 24, 25, 72, 74*, 75 † miocenicus 75, 76 † schuberti 17, 19, 25, 72, 76, 76* sp. 74*, 75 civitatus, Symphurus 362, 364, 364* † claibornensis, Eosolea 15 clarus, Laeops 193 Cleisthenes 210, 214, 216 herzensteini 217, 217* pimetorum 217 clerveleyi, Solea 295 Clidoderma 210, 243, 244, 245 asperrimum 18, 21, 27, 245, 245* coarctus, Parabothus 162 Coccolus 157 cochinensis, Zebrias 321 cocosensis, Engyprosopon 202*, 203 coenosus, Pleuronichthys 246, 247, 248* Colistium 62, 65, 66, 68 guentheri 66, 67, 67*, 68 nudipinnis 66, 67, 67*, 68 Schwarzhans: Pleuronectiformes 377 † collatus, Psettodes 15, 16, 17, 19, 23, 58, 60*, 61* colorata, Poecilopsetta 265, 267 comifer, Achirus 271 commersoniana, Synaptura 18, 308, 308* † concaviventris, Etropus 15, 20, 22, 156, 156* † concavus, (Pleuronectidarum) 15 conspersus, Pleuronectes 168 constellatus, Bothus 158, 159, 160* † contortus, Bothus 15, 17 cooperi, Metoponops 149 corallinus, Samariscus 261 coreanicus, Paralichthys 122 † corius, Rhombus 15, 17 cornuta, Aesopia 316, 317, 317* † cornuta, Quenselia 15, 21, 25, 26, 44, 291, 292, 293, 293*, 295 cornutus, Orthopsetta 149, 152, 153* cornutus, Pleuronichthys 18, 21, 27, 247 † corpulentus, Solea 15 Coryphaesopia 316 Coryphyllus 324, 326 costae, Samaris 259 † cottreaui, Solea 15 craticulus, Zebrias 321 cristatus, Lophorhombus 185 cristatus, Pleuronectes 91 cristatus, Samaris 258, 259, 260* crossolepis, Pseudaesopia 320 Crossolepis 186 Crossorhombus 104, 157, 158, 199, 201, 204 azureus 204, 205* howensis 204 kanekonis 204, 205* valderostratus 204, 205* crossotus, Etropus 152, 153, 154, 154* crumenalis, Pelecanichthys 208 Cryptops 323 ctenosquamis, Spinirhombus 126 cuneata, Dicologlossa 18, 47*, 133, 286, 287, 294, 295, 297 Curioptera 69 cyaneus, Aseraggodes 325, 326, 326* cycloidea, Ancylopsetta 106, 107, 108* cyclops, Pleuronectes 91 Cyclopsetta 38, 48, 104, 109, 135, 136, 141, 145 chittendeni 141, 142*, 143 fimbriata 141, 143, 143* maculifera 141 panamensis 19, 20, 22, 141, 143, 144* querna 109, 141, 142*, 143 † transitus 17, 20, 22, 143, 145* cyclosquamus, Etropus 153 Cynicoglossus 246 Cynoglossoides [VON BONDE 1922] 340 Cynoglossoides [SMITH 1949] 340 cynoglossus, Cynoglossus 342, 358, 359* Cynoglossus 36, 40, 52, 338, 339, 340, 341, 342, 359, 361 abbreviatus 342, 348, 349* acutirostris 342 † altus 15, 356 arel 342, 351, 351*, 352, 353 attenuatus 341, 342 bilineatus 18, 22, 27, 342, 344, 348, 350*, 351 blochi 342, 350*, 351 borneensis 342, 344, 345* Piscium Catalogus, Part Otolithi piscium, Vol. 2 broadhursti 342, 355, 357* browni 342 cadenati 342 canariensis 342, 343, 343*, 344 capensis 342 carpentari 342, 359, 361* cynoglossus 342, 358, 359* dispar 341, 342, 348, 350* dollfusi 342 dubius 342, 344, 345* durbanensis 342 ecaudatus 341, 342 feldmanni 342, 347, 347* gilchristi 342, 356, 357*, 358 gracilis 342, 347, 348, 349* heterolepis 342, 346, 347* interruptus 342, 354, 354* itinus 342, 353, 354* japonicus 18, 22, 27, 342, 348, 350*, 351 joyneri 18, 22, 27, 342, 353, 353* kapuasensis 342, 346, 347* kopsi 342, 353, 354* lachneri 342 † leuchsi 15, 16, 17, 22, 24, 25, 342, 356, 358* lida 341, 342, 346, 346* lingua 340, 342, 351, 352, 352* macrophthalmus 342 macrostomus 342 maculipinnis 342, 356, 357* marleyi 342, 359 microlepis 342 microphthalmus 342 monodi 342 monopus 342, 358, 359* † obliqueventralis 16, 22, 26, 342, 343, 343* ogilbyi 342 puncticeps 342, 356, 357*, 358 quadrilineatus 342, 344, 346* robustus 342, 351, 352, 352*, 353 sealarki 341, 342, 355, 355* semifasciatus 342, 358, 359* semilaevis 342, 347, 348, 349* senegalensis 342, 344, 345* sinusarabici 342 suyeni 342 trigrammus 342, 348, 349* unicolor 342, 350*, 351 wandersi 342 zanzibarensis 342, 355, 355* cynoglossus, Glyptocephalus 225, 226* cynoglossus, Pleuronectes 223 Cynopsetta 219 cypho, Laeops 193 D Dageichthys 269, 280, 301 lakdoensis 301 dalgleishi, Arnoglossus 167, 168, 181, 182* danae, Monolene 197 darwini, Oncopterus 69, 70, 70* debilis, Arnoglossus 168, 181, 181* † decipiens, Bothus 15, 17 378 declivis, Achirus 273, 274* decurrens, Pleuronichthys 247, 248, 248* delagoensis, Samaris 259 Delothyris 197 delsmani, Etropus 153 deltae, Cynoglossus 358 dendritica, Ancylopsetta 107 dentatus, Hippoglossoides 220 dentatus, Japanolaeops 196 dentatus, Paralichthys 116, 117, 117*, 121 dentex, Hippoglossus 58 derentensis, Taratretis 70 desoutterae, Samariscus 261 Dexillichthys 269, 310 macrolepis 311, 312* muelleri 311 setiger 311 Dexillus 310 Dexiourius 340, 342 Dexistes 210, 223, 226, 228 rikuzenius 228, 230, 230* diabolicus, Symphurus 362 diagrammus, Pleuronectes 232 diaphanus, Bothus 159 diaphanus, Pleuronectes 168 Dicologlossa 48, 49, 269, 280, 281, 282, 291, 294 cuneata 18, 47*, 133, 286, 287, 294, 295, 297 hexophthalma 18, 291, 294, 295, 295*, 296 † patens 16, 18, 19, 21, 24, 25, 294, 296, 297* dignabilis, Pseudopleuronectes 238 dilecta, Ancylopsetta 107, 108, 108* dimorphus, Platophrys 204 dinoceros, Orthopsetta 149 diomedianus, Symphurus 362 diplasios, Arelia 344 diplospilus, Pseudorhombus 125 dipterygia, Plagusia 348 dispar, Cynoglossus 341, 342, 348, 350* diurus, Scophthalmus 235 Dollfusetta 166 dollfusi, Cynoglossus 342 Dollfusiana 166 Dollfusichthys 340 † dominicensis, Syacium 15, 20, 22, 136, 139, 140* † dorsolobata, Taeniopsetta 15, 21, 188, 189* † dorsolobatus, (Bothidarum) 15 Dorsopsetta 109 norma 109, 143 Drepanopsetta 219 dubiosa, Monolene 197 dubius, Aseraggodes 325 dubius, Cynoglossus 342, 344, 345* dubius, Hippoglossoides 220, 222*, 223 dumerili, Apionichthys 280, 280* dupliciocellatus, Pseudorhombus 125, 129, 130* durbanensis, Cynoglossus 342 dwinensis, Platessa 231 E ecaudatus, Cynoglossus 341, 342 Echinosolea 290 ectenes, Etropus 153 elassodon, Hippoglossoides 220, 221* elegans, Tarphops 135 elevatus, Pseudorhombus 125, 131, 131* ellipticus, Bothus 158 elongata, Platessa 225 elongatus, Ammotretis 69, 69* elongatus, Arnoglossus 168 elongatus, Cynoglossus 351 elongatus, Microbuglossus 302, 303* † elongatus, Pleuronectes 15, 18 elongatus, Symphurus 362*, 363 elongatus, Xenobuglossus 295 Embassichthys 210, 245, 246 bathybius 246 Engyophrys 38, 104, 105, 189, 190, 191, 192 ciliaris 191 sanctilaurenti 190, 191, 192* sentus 191 Engyprosopon 8, 51, 56, 104, 157, 158, 199, 201, 204 arenicola 202 bellonaensis 202 bleekeri 202, 203, 203* borneensis 202 cocosensis 202*, 203 filimanus 202, 202*, 203 grandisquama 202, 203, 203* hawaiensis 202 hensleyi 202 hureaui 202 latifrons 202 longipelvis 202 longipterum 202 macrolepis 202 macroptera 202 maldivensis 202 mogkii 201 multisquamata 202 natalensis 202 raoulensis 202 regani 202 rostratum 202 sechellensis 202 septempes 202 smithi 202 ui 19, 135 xenandrus 201, 202, 202* entomorhynchus, Arnoglossus 175 Eopsetta 48, 49, 210, 212, 227, 232 grigorjewi 212 jordani 18, 21, 212, 213, 213* † Eosolea 13 † claibornensis 15 † texana 17 Errex 225 erumei, Psettodes 57, 58, 59* Etropus 38, 104, 145, 149, 152 † concaviventris 15, 20, 22, 156, 156* crossotus 152, 153, 154, 154* cyclosquamus 153 delsmani 153 ectenes 153 intermedius 153, 154, 154* longimanus 153, 154, 155, 155* Schwarzhans: Pleuronectiformes 379 microstomus 153, 155, 155* peruvianus 153 rimosus 153 Euchalarodus 230 Eucitharus 71 † belgicus 15 † circularis 15 † lusitanicus 16 † miocenicus 16, 18, 24 † schuberti 17 Eupnoea 360 Euporista 360 Euryglossa 311 Eurypleura 311 evermanni, Atherestes 215, 216* excisiceps, Teratorhombus 129 exilis, Lyopsetta 18, 21, 27 † extremus, Arnoglossus 15, 20, 27, 168, 178, 178* F fallax, Symphurus 362 † fangariensis, (Pleuronectidarum) 15, 18 fasciata, Plagusia 363 fasciatus, Achirus 271 fasciatus, Nodogymnus 278 fasciatus, Pleuronectes 283 fasciatus, Samariscus 261 fasciatus, Zebrias 321 fasciolaris, Symphurus 362 feldmanni, Cynoglossus 342, 347, 347* fernandezianus, Paralichthys 116 ferruginea, Limanda 18, 227, 228, 229* filiger, Aseraggodes 325, 326, 327* filimanus, Engyprosopon 202, 202*, 203 filipectoralis, Samariscus 261 fimbriata, Cyclopsetta 141, 143, 143* fimbriatus, Trinectes 271 finis, Soleonasus 280 fischeri, Solea 271 fisoni, Arnoglossus 168 flavilatus, Pelotretis 251, 252, 253* flesoides, Pleuronectes 235 flesoides, Rhombosolea 254 flesus, Platichthys 18, 21, 24, 53, 55*, 235, 237* † flexodorsalis, Peltorhamphus 15, 22, 27, 334, 335, 337* fluviatilis, Trinectes 271 foliacea, Solea 312 † foliformis, Rhombus 15, 18 fonsecensis, Trinectes 271, 272, 272* † fordycei, Achirus 15, 337 † fordycei, Peltorhamphus 15, 22, 27, 334, 337, 338* formoana, Rhinoplagusia 349 formosanus, Pseudorhombus 126 fragilis, Orthopsetta 149, 150*, 151 frechkopi, Microchirus 282, 292 † frequens, Buglossidium 15, 285, 286, 288 † frequens, Microchirus 14, 15, 21, 23, 24, 25, 51, 283, 285, 285*, 290 frontalis, Gastropsetta 108, 109, 109* fulvomarginata, Solea 298 fuscus, Hemirhombus 147 fuscus, Symphurus 362 Piscium Catalogus, Part Otolithi piscium, Vol. 2 G galathaea, Chascanopsetta 207 gallus, Lophonectes 185, 185* garmani, Achirus 273, 275, 275*, 276 Gastropsetta 38, 104, 105, 106, 108 frontalis 108, 109, 109* gesneri, Rhombus 159 gigantea, Psettina 186 gigas, Hippoglossus 213 gilberti, Citharichthys 147, 147* gilchristi, Chascanopsetta 207 gilchristi, Cynoglossus 342, 356, 357*, 358 gilesi, Symphurus 360, 362, 366*, 367 gilli, Pleuronectes 246 ginsburgi, Symphurus 362 † glaber, Solea 16 glabra, Platessa 231, 236 glacialis, Liopsetta 230, 231, 231* glossa, Plagiopsetta 257, 258, 258* Glossichthys 360 Glyptocephalus 10, 11, 44, 45, 48, 49, 210, 223, 225 cynoglossus 225, 226* stelleri 225 zachirus 19, 21, 47*, 225, 226*, 227* goniographicus, Hippoglossus 58 goreensis, Cynoglossus 344 gorgonae, Symphurus 362 gracilis, Cynoglossus 342, 347, 348, 349* gracilis, Laeops 193 Grammatobothus 104, 157, 158, 162 † awamoaensis 15, 20, 27, 163, 164, 165* krempfi 163 pennatus 163 polyophthalmus 162, 163, 163*, 164 † radwanskae 16, 20, 25, 163, 164* Grammichthys 272 grandisquama, Engyprosopon 202, 203, 203* grandisquama, Nematops 269, 269* grandisquamis, Plagusia 351 grandiviri, Catathyridium 273, 276 † Granulithus 13, 269, 316, 317 † granum 16, 21, 23, 317, 318* † granum, Aesopia 16, 317 † granum, Granulithus 16, 21, 23, 317, 318* † grenfelli, Arnoglossus 16, 20, 27, 168, 180, 180* grigorjewi, Eopsetta 212 groenlandicus, Microstomus 246 grohmanni, Arnoglossus 168, 170, 171* gronovii, Solea 273 guatimalensis, Citharichthys 147 guentheri, Colistium 66, 67, 67*, 68 guentheri, Laeops 193, 193* † guestfalica, Solea 16, 82 guibei, Bothus 158 guineensis, Hemirhombus 136 gunteri, Syacium 136, 138, 139* guttata, Plagusia 348 guttulata, Hypsopsetta 249, 250, 251* guttulatus, Aseraggodes 324, 325 Gymnachirus 35, 269, 270, 277 melas 278, 279* 380 nudus 277 gymnorhinus, Orthopsetta 149 H haackeanus, Aseraggodes 325 hamiltoni, Cynoglossus 358 Haplozebrias 320 hardenbergi, Cynoglossus 347 harmandi, Solea 314 hartzfeldi, Rendahlia 332, 334, 335* hawaiensis, Engyprosopon 202 hawaiiensis, Poecilopsetta 267 heckelii, Peloria 159 hectoris, Pseudorhombus 183 hedleyi, Pardachirus 329, 330, 331* heini, Microbuglossus 302, 303* † heletroides, (Bothidarum) 16 † helvecianus, Pseudorhombus 16 Hemirhombus 135 hensleyi, Engyprosopon 202 herrei, Aseraggodes 325 herzensteini, Cleisthenes 217, 217* herzensteini, Pseudopleuronectes 238, 239* Heterobuglossus 269, 310 aspilos 310, 311* heterolepis, Cynoglossus 342, 346, 347* heterolepis, Synaptura 310 Heteromycteris 18, 36, 45, 269, 330, 332, 334 capensis 332, 333* cheni 332 japonicus 332, 333* matsubarai 332 oculus 332, 333* proboscideus 332 heterophthalmus, Rhombus 159 Heteroprosopon 246 heterorhinos, Soleichthys 318, 319* hexophthalma, Dicologlossa 18, 291, 294, 295, 295*, 296 hexophthalmus, Microchirus 282 hilgendorfi, Paralichthys 116 Hippoglossina 38, 53, 104, 106, 109, 112, 113 bollmani 110 macrops 109, 110, 110* montemaris 110 mystacium 110 stomata 110, 111, 111* Hippoglossoides 44, 45, 48, 49, 210, 214, 218, 219, 223, 241 dubius 220, 222*, 223 elassodon 220, 221* platessoides 19, 21, 24, 220, 221* robustus 220 hippoglossoides, Reinhardtius 47*, 221, 223, 224* Hippoglossus 10, 11, 52, 210, 212, 213 hippoglossus 213, 214* stenolepis 19, 21, 213, 214, 214* hippoglossus, Hippoglossus 213, 214* hirtus, Pleuronectes 101 hispidus, Monochirus 290, 291* hollandi, Areliscus 348 † holleri, Arnoglossus 16, 20, 24, 25, 168, 170, 172, 173*, 286 Holonodus 320 holothuriae, Symphurus 362 hubbardi, Parophrys 232 humilis, Solea 302 † hunyadensis, (Pleuronectidarum) 16, 18 hureaui, Engyprosopon 202 huysmani, Samariscus 261, 262, 263* Hypoclinemus 269, 270, 276 mentalis 277, 277* paraguayensis 276, 277 Hypsopsetta 48, 49, 210, 245, 246, 247, 249 guttulata 249, 250, 251* I Icania 340, 342 † ignobilis, Limanda 16, 21, 23, 227, 228, 229* iijimae, Psettina 186*, 187 immaculatus, Cynoglossus 356 impar, Solea 298 imperialis, Arnoglossus 18, 20, 24, 167, 168, 169, 170, 171* † inconspectus, Arnoglossus 16, 172 indica, Solea 273 inermis, Platophrys 162 inermis, Poecilopsetta 267 Inopsetta 210, 226, 240 ishyra 240, 241, 241* inornatus, Samariscus 261 inscriptus, Trinectes 271 insignis, Vanstraelenia 303, 304, 304* intermedius, Asterorhombus 166 intermedius, Cynoglossus 346 intermedius, Etropus 153, 154, 154* intermedius, Hippoglossus 137 interruptus, Cynoglossus 342, 354, 354* inusita, Cynoglossus 352 † irregularis, (Pleuronectidarum) 16, 18, 22 ishyra, Inopsetta 240, 241, 241* isocles, Paralichthys 115, 116, 122, 123*, 125 isolepis, Isopsetta 18, 21, 242, 243, 243* Isopsetta 44, 210, 233, 241, 242 isolepis 18, 21, 242, 243, 243* Istiorhombus 124 italicus, Pleuronectes 236 itinus, Cynoglossus 342, 353, 354* J Japanolaeops 196 dentatus 196 japonica, Paraplagusia 18 japonica, Pseudaesopia 320, 320* japonicus, Arnoglossus 168 japonicus, Cynoglossus 18, 22, 27, 342, 348, 350*, 351 japonicus, Heteromycteris 332, 333* japonicus, Samariscus 261, 262* Japonolaeops 104, 189 jaubertensis, Rendahlia 332, 333, 334, 335* javanica, Plagusia 356 javanicus, Pseudorhombus 125, 127, 128*, 129 jenynsi, Catathyridium 275, 276, 276* jenynsi, Symphurus 362 jenynsii, Pseudorhombus 125, 131, 131*, 132 † Joleaudichthys 57 jordani, Eopsetta 18, 21, 212, 213, 213* Schwarzhans: Pleuronectiformes 381 jordani, Paralichthys 121 joyneri, Cynoglossus 18, 22, 27, 342, 353, 353* K kaianus, Aseraggodes 325 Kamoharaia 104, 207, 208 megastoma 208 kapuasensis, Cynoglossus 342, 346, 347* † karaganensis, Rhombus 16 Kareius 210, 226, 235, 236 bicoloratus 236, 239* katakurae, Hippoglossoides 220 kaupii, Arelia 351 keralensis, Zebrias 321 kessleri, Arnoglossus 170 kiensis, Parabothus 162 kingii, Hippoglossus 121 † kirchbergeana, Solea 16, 286 † kirchbergeanus, Microchirus 14, 16, 17, 18, 21, 24, 25, 51, 283, 286, 287* kitaharae, Laeops 193 kitaharae, Tanakius 223, 224, 225* kitt, Microstomus 246, 247* kleini, Solea 298, 301, 301* † klockenhoffi, Lepidorhombus 16, 20, 24, 95, 99, 99*, 100 klunzingeri, Achirus 273 klunzingeri, Aseraggodes 325, 326, 327* kobensis, Aseraggodes 325, 325*, 326 kobensis, Scaeops 204 krempfi, Grammatobothus 163 † kokeni, Arnoglossus 15, 16, 18, 20, 25, 26, 168, 170, 172, 174*, 175 † kokeni [BASSOLI 1906], Solea 16, 172, 296 † kokeni [SCHUBERT 1906], Solea 16, 296 † konkensis, Rhombus 16, 18 kopsi, Cynoglossus 342, 353, 354* kotthausi, Arnoglossus 168 kumperae, Ancylopsetta 107 kyaropterygium, Symphurus 362 Kyleia 166 L lachneri, Cynoglossus 342 lactea, Bathysolea 305, 306 lactea, Plagusia 367 Laeopichthys 192 Laeops 8, 51, 104, 189, 192 clarus 193 cypho 193 gracilis 193 guentheri 193, 193* kitaharae 193 lanceolata 193 macrophthalmus 193, 194, 194*, 196 natalensis 193 nigrescens 193, 194*, 196 nigromaculatus 193, 194, 194* parviceps 192, 193 pectoralis 193 † rharbensis 16, 21, 26, 193, 195, 196* sinusarabici 193 Piscium Catalogus, Part Otolithi piscium, Vol. 2 † splendens 17, 21, 25, 48, 192, 193, 195, 195* tungkongensis 193 variegata 193 laevis, Pleuronectes 91 lagoensis, Cynoglossus 343 Laiopteryx 86 lakdoensis, Dageichthys 301 Lambdopsetta 192 lanceolata, Laeops 193 † lapierrei, Arnoglossus 16, 20, 23, 168, 177, 177*, 178 † lapierrei, (Bothidarum) 16, 177 lascaris, Pegusa 18, 19 lascaris, Solea 14, 18, 298, 300, 300*, 301 lata, Platessa 235 laterna, Arnoglossus 14, 18, 24, 27, 122, 166, 167, 168, 168*, 169, 170, 172, 174, 175, 181 latidens, Microstomus 246 latifrons, Citharichthys 137 latifrons, Engyprosopon 202 † latior, Microchirus 16, 19, 21, 25, 283, 288, 288* † latior, Solea 16, 288 † latisulcatus, Citharus 16 latus, Peltorhamphus 334, 336, 336* latus, Samariscus 261 leei, Symphurus 362, 364, 364* † lenticularis, Solea 16 leopardinus, Bothus 158, 160 leotardi, Pleuronectes 168 Lepidoblepharon 34, 35, 37, 44, 48, 49, 64, 71, 84, 85, 86, 210 ophthalmolepis 85, 86* Lepidopsetta [GILL 1864] 210, 226, 233, 240, 241 bilineata 240, 240*, 241 mochigarei 240 Lepidopsetta [GÜNTHER 1880] 208 Lepidorhombus 11, 34, 48, 49, 80, 89, 90, 92, 93, 250 † angulosus 15, 20, 24, 95, 96, 97, 98*, 99 boscii 10, 18, 94, 95, 95* † klockenhoffi 16, 20, 24, 95, 99, 99*, 100 † subtriangularis 15, 17, 20, 23, 24, 25, 82, 94, 96, 96*, 97*, 98, 99 whiffiagonis 19, 20, 24, 46*, 92, 93, 94*, 95, 98, 99 leporina, Rhombosolea 253, 254, 255* Leptolaeops 192 lentiginosus, Rhombus 129 lethostigma, Paralichthys 116, 117, 118, 119*, 121 † leuchsi, Cynoglossus 15, 16, 22, 24, 25, 342, 356, 358* leucorhynchus, Achiroides 314 levisquamis, Pseudorhombus 125, 126*, 127 Liachirus 323, 328, 329 lida, Cynoglossus 341, 342, 346, 346* lighti, Cynoglossus 353 ligulatus, Symphurus 362 limanda, Hippoglossoides 220 limanda, Limanda 18, 21, 24, 227, 228* Limanda 44, 210, 223, 226, 227, 229, 233, 240 † aomoriensis 15, 17 aspera 227, 228, 229* ferruginea 18, 227, 228, 229* † ignobilis 16, 21, 23, 227, 228, 229* limanda 18, 21, 24, 227, 228* † otomoi 16, 18 proboscidea 227 punctatissima 227 382 sakhalinensis 227 Limandella 238 limandoides, Pleuronectes 220 limandula, Pleuronectes 227 lineata, Solea 318 lineatus, Achirus 273 lineolatus, Cynoglossus 344 lingua, Cynoglossus 340, 342, 351, 352, 352* linguatula, Citharus 18, 71, 72, 73*, 74, 75 lingula, Monochirus 283 linnei, Hippoglossus 213 lioderma, Pleuronectes 91 Lioglossina 34, 38, 104, 106, 110, 113, 115 oblonga 113, 114, 114* tetrophthalmus 113, 114, 114* liolepis, Xystreurys 111, 112, 112* Liopsetta 210, 226, 230, 233, 235 glacialis 230, 231, 231* obscura 230, 231, 231* pinnifasciata 230 putnami 230, 231, 231* lipophthalmus, Typhlachirus 323 † lobata, Platessa 16 longidorsale, Syacium 136 longimanus, Etropus 153, 154, 155, 155* longimanus, Samariscus 261 longipelvis, Engyprosopon 202 longipterum, Engyprosopon 202 longleyi, Syacium 138 † longus, Arnoglossus 16, 20, 27, 52, 167, 168, 178, 179*, 184 Lophonectes 104, 165, 185 gallus 185, 185* Lophopsetta 90 lophoptera, Scianectes 194 Lophorhombus 185 lophotes, Arnoglossus 170 lorentzi, Achirus 273 lubbocki, Symphurus 362 lucapensis, Zebrias 321 lugubris, Chascanopsetta 19, 27, 46*, 135, 207, 207* lunatus, Bothus 158, 160, 160* lunulatus, Pleuronectes 159 luscus, Pleuronectes 235 lusitanica, Synaptura 306, 308, 309, 309* † lusitanicus, Citharus 16, 19, 24, 25, 72, 74*, 75, 82 † lusitanicus, Eucitharus 16, 72 luteum, Buglossidium 19, 281 luteus, Microchirus 282, 283, 284* luzonensis, Samariscus 261 luzonensis, Symphurus 362 Lyopsetta 48, 49, 210, 214, 217, 219, 220 exilis 18, 21, 27, 217, 218, 218* M maccullochi, Cynoglossus 356 machionessarum, Passer 159 macleayanus, Aseraggodes 325, 326, 327* macrocephalus, Paraplagusia 348 macrochirus, Nematops 269 macrognathus, Samariscus 261 macrolepidota, Plagusia 351 macrolepidotus, Citharoides 79, 80* macrolepis, Ammotretis 69 macrolepis, Dexillichthys 311, 312* macrolepis, Engyprosopon 202 macrolepis, Paracitharus 77, 78*, 79* macrolepis, Samaris 259 macrolophus, Arnoglossus 176 macrophthalmus, Cynoglossus 342 macrophthalmus, Laeops 193, 194, 194*, 196 macrophthalmus, Symphurus 362 macrops, Citharichthys 147, 148, 148* macrops, Hippoglossina 109, 110, 110* macroptera, Engyprosopon 202 macropterus, Rhombus 161 macrorhynchos, Plagusia 352 macrostoma, Arnoglossus 168, 169, 169* macrostomus, Cynoglossus 342 maculata, Chascanopsetta 207 maculata, Mancopsetta 11, 209, 209* maculatus, Pleuronectes 92 maculatus, Samariscus 261 maculatus, Solea 302 maculatus, Trinectes 270, 271, 271* maculifera, Cyclopsetta 141 maculipinna, Monolene 197, 198*, 199 maculipinnis, Arnoglossus 168 maculipinnis, Cynoglossus 342, 356, 357* maculosus, Pleuronectes [CUVIER 1829] 129 maculosus, Pleuronectes [GIRARD 1856] 120 maderensis, Rhombus 159 maeoticus, Pleuronectes 91 malayanus, Pseudorhombus 125, 127, 127* maldivensis, Engyprosopon 202 maldivensis, Marleyella 264 maldiviensis, Symphurus 362 malhensis, Parabothus 162 Mancopsetta 10, 34, 39, 40, 41, 44, 45, 104, 105, 208, 210 andriashevi 209 maculata 11, 209, 209* milfordi 46*, 208*, 209 mancus, Bothus 158, 161, 161* mangili, Pleuronectes 283 margaritifera, Solea 299 marginata, Synaptura 308 marginatus, Symphurus 362 mariajorisae, Orthopsetta 149 marisrubri, Arnoglossus 168 Marleyella 35, 42, 56, 210, 211, 264, 265 bicolorata 55, 264, 265* maldivensis 264 marleyi, Cynoglossus 342, 359 marmorata, Synaptura 310 marmoratus, Pardachirus 328, 329, 330, 331* marmoratus, Symphurus 362 matsubarai, Heteromycteris 332 matsuurae, Reinhardtius 223 maximus, Hippoglossus 213 maximus, Scophthalmus 7, 91, 92* mazatlanus, Achirus 273, 274, 275* mbaoensis, Solea 295 † medius, Phrynorhombus 16, 20, 24, 102, 103, 104* megagnatha, Chascanopsetta 207 megalepis, Poecilopsetta 267 megastoma, Kamoharaia 208 Schwarzhans: Pleuronectiformes 383 melampetalus, Cynoglossus 351 melanochira, Solea 298 melanogaster, Pleuronectes 117 melanopterus, Plagusia 358 melanorhynchus, Brachirus 312, 314, 315* melanospilos, Pardachirus 329, 330, 331* melanostictus, Aseraggodes 325 melanostictus, Psettichthys 242, 242* melanurus, Symphurus 362 melas, Gymnachirus 278, 279* melasma, Trichopsetta 190, 191* melasmatotheca, Symphurus 362 melissi, Bothus 158 mentalis, Hypoclinemus 277, 277* meridionalis, Symphurus 362 mertensi, Monolene 189, 197 Metoponops 148 Microbuglossus 269, 280, 301 elongatus 302, 303* heini 302, 303* ovatus 301, 302, 303* microcephalus, Pleuronectes 246 microcephalus, Soleichthys 318, 319, 319*, 320, 321 Microchiropsis 281 Microchirus 24, 25, 51, 269, 280, 281, 290, 291, 295 boscanion 281, 282, 283, 284* frechkopi 282, 292 † frequens 14, 15, 21, 23, 24, 25, 51, 283, 285, 285*, 290 hexophthalmus 282 † kirchbergeanus 14, 16, 17, 18, 21, 24, 25, 51, 283, 286, 287* † latior 16, 19, 21, 25, 283, 288, 288* luteus 282, 283, 284* variegatus 18, 19, 21, 24, 25, 281, 282, 282*, 283, 284, 286, 288 † wienrichi 17, 21, 24, 283, 286, 287, 288, 289* wittei 282, 292 microchirus, Pleuronectes 283 micrognathus, Chascanopsetta 207 micrognathus, Pseudorhombus 125 microlepidotus, Aseraggodes 325 microlepis, Austroglossus 306, 307 microlepis, Cynoglossus 342 microlepis, Symphurus 362 microphthalmus, Cynoglossus 342 microphthalmus, Neolaeops 166, 166* microphthalmus, Trinectes 271 microps, Citharichthys 155 microps, Cynoglossus 348 microps, Paralichthys 116, 121, 122* microstoma, Arnoglossus 168 microstoma, Chascanopsetta 207 microstoma, Monolene 196, 197, 198, 199* microstoma, Nematops 269 microstoma, Platophrys 204 Microstomus 44, 45, 210, 245, 246, 247 achne 246 kitt 246, 247* pacificus 19, 21, 246 shuntovi 246 microstomus, Etropus 153, 155, 155* microstomus, Pleuronectes 246 microtenus, Ancylopsetta 107, 108, 108* micrurum, Syacium 11, 135, 136, 137* milfordi, Mancopsetta 46*, 208*, 209 Piscium Catalogus, Part Otolithi piscium, Vol. 2 millari, Rhombosolea 254 † minor, Rhombus 16 minor, Symphurus 362 minutus Monochirus 283 † miocenica, Rhombus 16, 18 † miocenicus, Arnoglossus 16, 170, 172 † miocenicus, Citharus 75, 76 † miocenicus, Eucitharus 16, 18, 24, 75 misakius, Pseudorhombus 126 Mischommatus 310 mochigarei, Lepidopsetta 240 mogkii, Engyprosopon 201 mollis, Pleuronectes 271 mongonuiensis, Arnoglossus 185 Monochirus 269, 280, 281, 290 hispidus 290, 291* monodi, Cynoglossus 342 Monodichthys 332 Monolene 38, 51, 104, 105, 189, 192, 193, 196, 197 antillarum 197, 198* asaedae 197 atrimana 197 danae 197 dubiosa 197 maculipinna 197, 198*, 199 mertensi 189, 197 microstoma 196, 197, 198, 199* † priscus 16, 21, 23, 197, 199, 200* † prudhommae 16, 178 sessilicauda 197, 198* monopus, Cynoglossus 342, 358, 359* monopus, Rhombosolea 254 montemaris, Hippoglossina 110 moltoni, Arnoglossus 169 morrowi, Pardachirus 329 mortoniensis, Pleuronectes 129 moseri, Verasper 243, 244 muelleri, Arnoglossus 168 muelleri, Dexillichthys 311 multifasciata, Aesopia 318 multimaculatus, Pseudorhombus 131 multiradiatus, Pseudorhombus 131 multirastris, Arnoglossus 168 multisquamata, Engyprosopon 202 munroi, Zebrias 321 myriaster, Bothus 158, 161, 161* mystacium, Hippoglossina 110 Myzopsetta 227 N nadeshnyi, Acanthopsetta 219, 219* nalaka, Pleuronectes 58 naresi, Thysanopsetta 206, 206* nasuta, Solea 298, 300, 300*, 301 natalensis, Engyprosopon 202 natalensis, Laeops 193 natalensis, Poecilopsetta 267, 268* natalensis, Pseudorhombus 125 nattereri, Achiropsis 280 Neachiropsetta 208 nebularis, Platophrys 159 nebulosus, Apionichthys 280 384 nebulosus, Symphurus 362 neglectus, Pseudorhombus 125, 129, 130* Nematops 210, 268 chui 269 grandisquama 269, 269* macrochirus 269 microstoma 269 Nematozebrias 320 Neoetropus 210 Neolaeops 104, 165, 166, 168 microphthalmus 166, 166* Neorhombus 124 nephelus, Pleuronichthys 247 nicholsi, Nodogymnus 278 nielseni, Samariscus 261 niger, Brachirus 312, 313, 313* nigrescens, Laeops 193, 194*, 196 nigrescens, Symphurus 19, 22, 26, 360, 362, 367, 367* nigrolabeculata, Plagusia 356 nigromaculatus, Laeops 193, 194, 194* nigromanus, Pleuronectes 225 nigropinnatus, Cynoglossus 354 nigrostriolata, Solea 318 Nodogymnus 35, 269, 270, 277, 278 fasciatus 278 nicholsi 278 texae 278, 279* williamsoni 278 zerbrinus 278 † nolfi, Pseudopardachirolithus 16, 22, 23, 327, 328, 329* norma, Dorsopsetta 109, 143 Normanetta 328 normani, Aseraggodes 325 normani, Heteromycteris 334 normani, Poecilopsetta 267 normani, Symphurus 362 norvegicus, Phrynorhombus 102, 103, 103* notata, Hippoglossina 112 notata, Plagusia 348 Notosema 106, 107 novae, Achirus 273 novaecambriae, Paralichthys 131 novaezeelandiae, Bowenia 254 novaezeelandiae, Brachypleura 86, 87, 87*, 226 novaezeelandiae, Peltorhamphus 334, 335, 336* † novaezeelandiae, Rhombocitharus 16, 20, 27, 81, 83, 84* novemfasciatus, Symphurus 362 † novus, Arnoglossus 16, 20, 27, 52, 167, 168, 179, 180*, 184 nudipinnis, Colistium 66, 67, 67*, 68 nudus, Gymnachirus 277 nudus, Rhombus 168 O † obliqueventralis, Cynoglossus 16, 22, 26, 342, 343, 343* † obliquus, (Bothidarum) 16, 103 oblonga, Lioglossina 113, 114, 114* obscura, Liopsetta 230, 231, 231* oceanica, Limanda 227 ocellaris, Platessa 117 ocellata, Quenselia 282, 290, 292*, 293 ocellata, Taeniopsetta 187, 188* ocellatus, Aseraggodes 325 ocellatus, Bothus 158, 159, 160* ocellatus, Hippoglossus 136 ocellatus, Pleuronichthys 247 ocellatus, Psammodiscus 70 ocellatus, Symphurus 362 ocellifer, Pseudorhombus 132 octoculatus, Tosarhombus 203 oculellus, Symphurus 362, 364, 364* oculocirris, Pseudorhombus 125 oculus, Heteromycteris 332, 333* Odontolepis 360 † oedelemensis, Psettodes 16, 58, 59, 60 ogilbyi, Cynoglossus 342 oligodon, Pseudorhombus 125, 130, 130*, 134 oligolepis, Plagusia 351 oligolepis, Tarphops 134*, 135 oligomerus, Symphurus 362 olivaceus, Paralichthys 18, 19, 20, 27, 115, 116, 118, 121, 122, 123* ommaspilus, Symphurus 362 ommatus, Paralichthys 107 Oncopterus 62, 65, 68, 69 darwini 69, 70, 70* opercularis, Achirus 273 ophthalmolepis, Lepidoblepharon 85, 86* ophyras, Paralichthys 117 † orbicularis, (Pleuronectidarum) 16 orbicularis, Scaeops 203 orbignyana, Paralichthys 116, 116*, 117 orbisculus, Trichopsetta 190 orientalis, Brachirus 311, 312, 313*, 314 orientalis, Symphurus 362, 366, 366* ornatus, Achirus 362 ornatus, Samaris 259 Orthopsetta 104, 145, 146, 148, 153 amblybregmatus 149 arctifrons 149, 151, 152* cornutus 149, 152, 153* dinoceros 149 fragilis 149, 150*, 151 gymnorhinus 149 mariajorisae 149 sordidus 20, 148, 149, 150*, 151 stigmaeus 20, 149, 149*, 151 xanthostigma 20,149, 151, 151* orthorhynchus, Hippoglossus 58 os, Cynoglossus 346 † otomoi, Limanda 16, 18 ottonis, Apionichthys 280 ovale, Syacium 55, 56, 136, 137, 138, 139*, 158, 200 ovalis, Ammotretis 69 ovalis, Bothus 158, 161 ovatus, Microbuglossus 301, 302, 303* oxyrhynchos, Plagusia 358 oxyrhynchus, Arnoglossus 168 P pacificus, Microstomus 19, 21, 246 paetulus, Hemirhombus 137 paitensis, Symphurus 362 palad, Platophrys 129 pallasii, Pleuronectes 235 pan, Brachirus 312, 314, 315* Schwarzhans: Pleuronectiformes 385 panamensis, Cyclopsetta 19, 20, 22, 141, 143, 144* panamensis, Solea 271 panoides, Anisochirus 312, 314, 316* pantherinus, Bothus 158, 159, 159*, 160 papillosum, Syacium 136, 137, 138*, 140 papillosus, Zeugopterus 101 Parabothus 104, 157, 158, 162 amaokai 162 chlorospilus 162, 162* coarctus 162 kiensis 162 malhensis 162 polylepis 162 taiwanensis 162 violaceus 162 Parachirus 269, 323, 330 xenicus 330 Paracitharus 11, 70, 71, 72, 77, 78 † angustus 11, 15, 20, 25, 77, 78, 79* macrolepis 77, 78*, 79* Paradicula 310 paraguayensis, Hypoclinemus 276, 277 Paralichthodes 27, 28, 29, 33, 34, 40, 42, 44, 62, 63, 64, 66, 71, 211 algoensis 62, 64, 65, 65* Paralichthys 34, 38, 52, 104, 106, 107, 108, 110, 113, 114, 124 adspersus 46*, 116, 117, 121, 121* aestuarius 116 albiguttata 107, 116, 117, 118*, 119 bicyclophorus 116 brasiliensis 116, 119, 119*, 121 caeruleosticta 116 californicus 18, 20, 114, 115, 116, 120, 120*, 121, 122 dentatus 116, 117, 117*, 121 fernandezianus 116 hilgendorfi 116 isocles 115, 116, 122, 123*, 125 lethostigma 116, 117, 118, 119*, 121 microps 116, 121, 122* olivaceus 18, 19, 20, 27, 115, 116, 118, 121, 122, 123* orbignyana 116, 116*, 117 shmitti 116 squamilentus 107, 116, 117, 118, 118*, 119 triocellatus 116 tropicus 116, 119, 119* vorax 116 woolmani 116 Paralimanda 265 Paraplagusia 338, 339, 340, 341, 342, 348, 359 † alta 15, 356 bilineata 18 , 348 japonica 18, 348 † roseni 17, 356 Pardachirus 36, 45, 269, 323, 326, 327, 328 hedleyi 329, 330, 331* marmoratus 328, 329, 330, 331* melanospilos 329, 330, 331* morrowi 329 pavoninus 19, 22, 27, 329, 330, 331* poropterus 329 Parophrys 48, 49, 210, 226, 232, 233 vetulus 19, 21, 47*, 232, 233* parviceps, Laeops 192, 193 parvimanus, Rhombus 159 Piscium Catalogus, Part Otolithi piscium, Vol. 2 parvus, Symphurus 362 passarinus, Pleuronectes 2 passer, Pleuronectes 235 patagonicus, Paralichthys 116 † patens, Dicologlossa 16, 18, 19, 21, 24, 25, 294, 296, 297* † patens, Solea 16, 296 paulistanus, Trinectes 271, 272* pavo, Rhombus 161 pavonina, Platessa 91 pavoninus, Pardachirus 19, 22, 27, 329, 330, 331* pectoralis, Austroglossus 306, 307, 307* pectoralis, Laeops 193 pegusa, Solea 300 Pegusa 296, 297 lascaris 18, 19 Pelecanichthys 104, 206, 207 crumenalis 208 pelicanus, Symphurus 362 pellegrini, Cynoglossus 348 pellucidus, Thyris 197 Peloria 157 Pelotretis 27, 35, 40, 210, 250, 251, 252 flavilatus 251, 252, 253* Peltorhamphus 12, 35, 36, 40, 65, 210, 269, 330, 331, 334 † flexodorsalis 15, 22, 27, 334, 335, 337* † fordycei 15, 22, 27, 334, 337, 338* latus 334, 336, 336* novaezeelandiae 334, 335, 336* tenuis 19, 22, 27, 334, 336, 338* penescalaris, Zebrias 321 pennatus, Grammatobothus 163 † pentagonalis, Brachypleura 16, 20, 24, 86, 87, 88, 88* † pentagonalis, (Pleuronectidarum) 16, 88 pentophthalmus, Pseudorhombus 19, 27, 125, 132, 132* perarcuatus, Pleuronectes 240 percocephala, Platessa 122 Perissias 38, 104, 105, 158, 189, 192 taeniopterus 192 persimilis, Aseraggodes 325 peruvianus. Etropus 153 Phrynorhombus 10, 11, 89, 100, 102 † bassolii 15, 102 † medius 16, 20, 24, 102, 103, 104* norvegicus 102, 103, 103* regius 102, 103 Phyllichthys 269, 310, 314, 315, 316 punctatus 314, 315, 316, 316* sclerolepis 315 sejunctus 315 picta, Plagusia 367 pictus, Pleuronectes 161 pilosa, Solea 273 piger, Symphurus 362 pimetorum, Cleisthenes 217 pinangensis, Cantoria 351 pinguis, Pleuronectes 223 pinnifasciata, Liopsetta 230 pinnifasciatus, Azygopus 263, 264, 264* Plagiopsetta 56, 210, 254, 257, 263 glossa 257, 258, 258* plagiusa, Symphurus 362*, 363 Plagiusa 360 plagusia, Symphurus 362, 362* 386 Plagusia 360 planus, Pleuronectes 238 platessa, Pleuronectes 7, 19, 21, 24, 51, 52, 232, 233, 234*, 235 Platessa 232 † lobata 16 † sector 17 platessoides, Hippoglossoides 19, 21, 24, 220, 221* Platichthys 53, 210, 226, 235, 236, 238, 241 flesus 18, 21, 24, 53, 55*, 235, 237* stellatus 19, 21, 53, 54*, 235, 236, 237*, 241 platophrys, Citharichthys 147 Platophrys 157, 158 Platotichthys 157 Platysomatichthys 221 plebeia, Rhombosolea 52, 252, 253, 254, 255* Pleuronectes 44, 210, 226, 232, 233, 235 † boerialensis 15 † elongatus 15, 18 pallasii 235 platessa 7, 19, 21, 24, 51, 52, 232, 233, 234*, 235 † sectoroides 17 † vulsus 17 (Pleuronectidarum) † acuminatus 15 † concavus 15 † fangariensis 15, 18 † hunyadensis 16, 18 † irregularis 16, 18, 22 † orbicularis 16 † pentagonalis 16 † splendens 17 † subrostratus 17 † syacioides 17 † temputulensis 17 Pleuronichthys 44, 45, 210, 245, 246 coenosus 246, 247, 248* cornutus 18, 21, 27, 247 decurrens 247, 248, 248* nephelus 247 ocellatus 247 ritteri 19, 21, 247, 249, 250* verticalis 247, 249, 249* plinthus, Poecilopsetta 266*, 267 Pluviopsetta 210 Pnictes 269, 279, 280 asphyxiatus 280 podas, Bothus 157, 158, 159, 159*, 160 Poecilopsetta 10, 45, 210, 264, 265, 268 albomaculata 266*, 267 albomarginata 267 beani 266*, 267 colorata 265, 267 hawaiiensis 267 inermis 267 megalepis 267 natalensis 267, 268* normani 267 plinthus 266*, 267 praelongo 266*, 267 vaynei 267 zanzibarensis 267, 268* poecilurus, Rhombus 203 pola, Platessa 246 † polonica, Bathysolea 16, 21, 25, 305*, 306 polylepis, Parabothus 162 polyophthalmus, Grammatobothus 162, 163, 163*, 164 polyspilus, Arnoglossus 168 polyspilus, Rhombus 129 polytaenia, Plagusia 346 Pomatopsetta 219 ponticus, Hippoglossus 213 ponticus, Scophthalmus 91 poropterus, Pardachirus 329 potous, Pleuronectes 352 † Praearchirolithus 12, 13, 269, 323, 327 † schultzei 17, 21, 23, 323, 324, 324*, 328 praecisus, Cynoglossus 353 praelongo, Poecilopsetta 266*, 267 † premaxima, Psetta 16 † priscus, Monolene 16, 21, 23 proboscidea, Limanda 227 proboscideus, Heteromycteris 332 profunda, Psettina 186 profundicola, Bathysolea 305, 305*, 306 prognathus, Chascanopsetta 207 prolatinaris, Symphurus 362 prorigera, Chascanopsetta 207 Protopsetta 216 † prudhommae, Arnoglossus 16, 20, 24, 168, 177*, 178 † prudhommae, Monolene 16, 178 Psammodiscus 62, 65, 70 ocellatus 70 Psetta 90 † premaxima 16 Psettichthys 210, 241, 242 melanostictus 242, 242* Psettina 104, 165, 186 brevirictis 186, 187* gigantea 186 iijimae 186*, 187 profunda 186 tosana 186 variegata 186 Psettinella 186 Psettodes 10, 12, 25, 27, 28, 34, 42, 48, 57, 62, 63 † bavayi 15, 19, 23, 58, 61, 62*, 64 belcheri 57, 58, 59* bennettii 58 † collatus 15, 16, 17, 19, 23, 58, 59, 60*, 61* erumei 58, 59* † oedelemensis 16, 58, 59, 60 † spinosus 17, 58, 59, 60 Psettylis 157 Pseudaesopia 269, 316, 318, 319, 321 crossolepis 320 japonica 320, 320* regani 319, 320 Pseudaustroglossus 306 Pseudocitharichthys 157 Pseudomancopsetta 208 † Pseudopardachirolithus 12, 13, 269, 323, 327 † nolfi 16, 22, 23, 327, 328, 329* † sulci 17, 22, 24, 25, 327, 328, 329* Pseudoplatichthys 210 Pseudopleuronectes 210, 226, 233, 238, 240, 241, 245 americanus 238, 239* Schwarzhans: Pleuronectiformes 387 herzensteini 238, 239* yokohamae 238, 239* Pseudorhombus 27, 34, 38, 42, 45, 52, 104, 106, 110, 116, 124, 134, 135, 136 annulatus 125, 130, 130*, 133 argus 125, 132*, 133 arsius 124, 125, 127, 129, 129*, 134 cinnamoneus 125, 126, 126* diplospilus 125 dupliciocellatus 125, 129, 130* elevatus 125, 131, 131* † helvecianus 16 javanicus 125, 127, 128*, 129 jenynsii 125, 131, 131*, 132 levisquamis 125, 126*, 127 malayanus 125, 127, 127* micrognathus 125 natalensis 125 neglectus 125, 129, 130* oculocirris 125 oligodon 125, 130, 130*, 134 pentophthalmus 19, 27, 125, 132, 132* quinquocellatus 125 spinosus 125 tenuirastrum 125, 132, 132*, 133 triocellatus 125, 131, 132, 133, 133* † weinfurteri 17, 18, 20, 25, 125, 133, 133* pterospilotus, Symphurus 362 punctatissima, Limanda 227 punctatissima, Synaptura 309 punctatus, Cynoglossus 353 punctatus, Phyllichthys 314, 315, 316, 316* punctatus, Zeugopterus 19, 20, 24, 100*, 101 puncticeps, Cynoglossus 342, 356, 357*, 358 purpureomaculatus, Areliscus 348 pusilla, Platessa 238 pusillus, Symphurus 362 putnami, Liopsetta 230, 231, 231* Q † quadratus, Arnoglossus 16, 21, 26, 167, 168, 170, 174, 175* quadridens, Pleuronectes 246 quadrilineatus, Cynoglossus 342, 344, 346* quadriocellata, Solea 293 quadrituberculatus, Pleuronichthys 248 quadrocellata, Ancylopsetta 106, 107, 107* quagga, Zebrias 321, 322, 323* Quenselia 24, 25, 44, 269, 280, 281, 282, 290, 295 † cornuta 15, 21, 25, 26, 44, 291, 292, 293, 293*, 295 ocellata 282, 290, 292*, 293 teophila 292*, 293 quenselii, Pleuronectes 246 querna, Cyclopsetta 109, 141, 142*, 143 quinquelineatus, Cynoglossus 344 quinquocellatus, Pseudorhombus 125 R radula, Taeniopsetta 187, 188, 188* † radwanskae, Grammatobothus 16, 20, 25, 163, 164* Ranularia 106 raoulensis, Engyprosopon 202 Piscium Catalogus, Part Otolithi piscium, Vol. 2 raptator, Trachypterophrys 207 rasile, Xystreurys 112, 113* regani, Engyprosopon 202 regani, Pseudaesopia 319, 320 regani, Symphurus 362 regius, Phrynorhombus 102, 103 Reinhardtius 10, 11, 42, 48, 49, 210, 211, 214, 215, 220, 221 hippoglossoides 47*, 221, 223, 224* Rendahlia 36, 269, 330, 332, 339 hartzfeldi 332, 334, 335* jaubertensis 332, 333, 334, 335* retiaria, Rhombosolea 253, 254, 257* reticulatus, Symphurus 362 † rharbensis, Laeops 16, 21, 26, 193, 195, 196* † rhenanus, Rhombocitharus 15, 16, 17, 20, 23, 24, 80, 81, 81* † rhenanus, Rhombus 16, 81, 96 Rhinoplagusia 340 † altus 356 Rhinosolea 12, 269 rhomaleus, Arelia 347 Rhombiscus 124 † Rhombocitharus 12, 13, 23, 24, 70, 80, 84 † biaculeatus 15, 20, 23, 81 † cauneillensis 15, 20, 23, 81, 83, 83* † circularis 15, 20, 23, 81, 83 † novaezeelandiae 16, 20, 27, 81, 83, 84* † rhenanus 15, 16, 17, 20, 23, 24, 80, 81, 81* † rhomboides 17, 20, 23, 81, 82*, 83 Rhomboides 90 † rhomboides, (Bothidarum) 17 † rhomboides, Rhombocitharus 17, 20, 23, 81, 82*, 83 rhomboides, Rhombus 159 rhomboides, Solea 159 Rhomboidichthys 157, 158 Rhombosolea 35, 39, 40, 42, 48, 49, 51, 210, 251, 252 leporina 253, 254, 255* plebeia 52, 252, 253, 254, 255* retiaria 253, 254, 257* tapirina 47*, 52, 53, 55*, 253, 254, 256* Rhombus 90 † altus 15, 17, 26 † corius 15, 17 † foliformis 15, 18 † karaganensis 16 † konkensis 16, 18 † minor 16 † miocenica 16, 18 rhombus, Scophthalmus 90, 91, 93* rhytisma, Symphurus 362 rikuzenius, Dexistes 228, 230, 230* rimosus, Etropus 153 ritteri, Pleuronichthys 19, 21, 247, 249, 250* robinsi, Bothus 158 robinsoni, Plagusia 349 robustus, Cynoglossus 342, 351, 352, 352*, 353 robustus, Hippoglossoides 220 † roseni, Paraplagusia 17, 356 † rosenthalensis, Bothus 17, 101 † rosenthalensis, Zeugopterus 17, 20, 23, 101, 101* roseus, Pleuronectes 235 rostrata, Myzopsetta 228 rostratum, Engyprosopon 202 rostratus, Ammotretis 68, 69, 69* 388 † rotunda, Solea 17, 19, 21, 25, 298, 299, 299* † rotundus, Gobius 17, 299 † rotundus, Solea 17, 18 roulei, Cynoglossus 347 rueppelli, Arnoglossus 10, 167, 168, 176, 176*, 177 rugosus, Platichthys 236 rumulo, Bothus 159 russellii, Platessa 129 russellii, Solea 308 S sakhalinensis, Limanda 227 salinarum, Brachirus 312 Samaris 34, 35, 40, 44, 45, 56, 210, 254, 258 costae 259 cristatus 258, 259, 260* macrolepis 259 † validus 17, 21, 27, 259, 260* Samariscus 8, 10, 56, 210, 254, 258 asanoi 261 corallinus 261 desoutterae 261 fasciatus 261 filipectoralis 261 huysmani 261, 262, 263* inornatus 261 japonicus 261, 262* latus 261 longimanus 261 luzonensis 261 macrognathus 261 maculatus 261 nielseni 261 sunieri 261, 263* triocellatus 52, 261, 262, 263* xenicus 261 sanctilaurenti, Engyophrys 190, 191, 192* sauvignyi, Synaptura 301 saxatilis, Pleuronectes 103 saxicola, Pleuronectes 225 sayademalhensis, Symphurus 362 sayaensis, Arnoglossus 168 scabra, Trinectes 271 Scaeops 201 scalaris, Zebrias 321 scapha, Caulopsetta 182, 183, 183*, 184 schrenki, Limanda 238 † schuberti, Citharus 17, 19, 25, 72, 76, 76* † schuberti, Eucitharus 17, 76 † schultzei, Praearchirolithus 17, 21, 23, 323, 324, 324*, 328 † schultzei, (Soleidarum) 17, 324, 328 schultzi, Symphurus 362 Scianectes 192 Scidorhombus 166 sclerolepis, Phyllichthys 315 Scophthalmus 25, 34, 89, 90, 100 aquosus 91, 92, 93* maximus 7, 91, 92* rhombus 90, 91, 93* scutifer, Pleuronectes 236 scutum, Achirus 273, 274, 275* sealarki, Cynoglossus 341, 342, 355, 355* sechellensis, Engyprosopon 202 † sector, Platessa 17 † sectoroides, Pleuronectes 17 sejunctus, Phyllichthys 315 selheimi, Brachirus 312 † semen, Bothus 17 semifasciatus, Cynoglossus 342, 358, 359* semilaevis, Cynoglossus 342, 347, 348, 349* senegalensis, Cynoglossus 342, 344, 345* senegalensis, Solea 19, 297, 298, 298* sentus, Engyophrys 191 septempes, Engyprosopon 202 septemstriatus, Symphurus 362, 366, 366* septentrionalis, Hippoglossus 213 serratus, Rhombus 159 setiger, Dexillichthys 311 setiger, Rhombus 103 shmitti, Paralichthys 116 shuntovi, Microstomus 246 siammakuti, Soleichthys 318 sibogae, Cynoglossus 353 † simplex, Solea 17, 18 simulator, Cynoglossus 344 sindensis, Cynoglossus 344 sinensis, Tephrinectes 63, 64* sinicus, Cynoglossus 344 sinusarabici, Aseraggodes 325 sinusarabici, Cynoglossus 342 sinusarabici, Laeops 193 slavae, Achiropsetta 209 smithi, Aseraggodes 325 smithi, Engyprosopon 202 smithi, Platophrys 161 smithii, Zebrias 320 solea, Solea 7, 14, 19, 21, 24, 27, 125, 296, 297, 298, 299, 300, 301* Solea 35, 51, 269, 280, 296, 297, 302 aegyptiaca 297, 298, 301* † angulata 15, 17 † antiqua 286 † approximata 15, 23, 24, 285, 286, 288, 290 † balangoensis 15, 17 † bartonensis 15 bleekeri 297, 298 † corpulentus 15 † cottreaui 15 fulvomarginata 298 † guestfalica 16, 82 impar 298 † kirchbergeana 16, 286 kleini 298, 301, 301* † kokeni [BASSOLI 1906]16, 172, 296 † kokeni [SCHUBERT 1906] 16, 296 lascaris 14, 18, 298, 300, 300*, 301 † latior 16, 288 † lenticularis 16 nasuta 298, 300, 300*, 301 † patens 16, 296 † rotunda 17, 19, 21, 25, 298, 299, 299* † rotundus 17, 18 senegalensis 19, 297, 298, 298* † simplex 17, 18 solea 7, 14, 19, 21, 24, 27, 125, 296, 297, 298, 299, 300, 301* † solitarius 17 Schwarzhans: Pleuronectiformes 389 † songgoensis 17, 18 stanalandi 298 † subglaber 17 † subvulgaris 17, 286, 287 † sulci 17 † taureri 17, 172 † tenuis 17, 18, 195 triophthalma 297, 298, 299* soleaeformis, Rhombus 137 (Soleidarum) † schultzei 17 Soleichthys 48, 49, 269, 316, 318, 320, 321 heterorhinos 318, 319* microcephalus 318, 319, 319*, 320, 321 siammakuti 318 Soleonasus 269, 279, 280 finis 280 Soleotalpa 279 † solitarius, Solea 17 † songgoensis, Solea 17, 18 sordidus, Citharichthys 19 sordidus, Orthopsetta 20, 148, 149, 150*, 151 sorsogonensis, Typhlachirus 323 Sphagomorus 57 spilopterus, Citharichthys 145, 146*, 147 spilurus, Rhomboidichthys 203 Spinirhombus 124 spinosus, Pleuronectes 161 † spinosus, Psettodes 17, 58, 59, 60 spinosus, Pseudorhombus 125 † splendens, Hippoglossoides 195 † splendens, Laeops 17, 21, 25, 48, 192, 193, 195, 195* † splendens, (Pleuronectidarum) 17, 195 squamilentus, Paralichthys 107, 116, 117, 118, 118*, 119 stampfli, Citharichthys 146*, 147 stanalandi, Solea 298 stellatus, Platichthys 19, 21, 53, 54*, 235, 236, 237*, 241 stelleri, Glyptocephalus 225 stellosus, Rhombus 91 stenolepis, Hipoglossus 19, 21, 213, 214, 214* stigmaeus, Citharichthys 19 stigmaeus, Orthopsetta 20, 149, 149*, 151 stigmatias, Paralichthys 107 stomata, Hippoglossina 110, 111, 111* stomias, Atherestes 19, 21, 215, 216* Strabozebrias 320 Strandichthys 310 strictus, Symphurus 362 † subglaber, Solea 17, 96 † subrostratus, (Pleuronectidarum) 17 † subtriangularis, Lepidorhombus 15, 17, 20, 23, 24, 25, 82, 94, 96, 96*, 97*, 98, 99 † subvulgaris, Solea 17, 286, 287 † sulci, Pseudopardachirolithus 17, 22, 24, 25, 327, 328, 329* † sulci, Solea 17, 328 sumatrana, Plagusia 358 sumatranus, Rhombus 159 sumichrasti, Citharichthys 147 sumptuosus, Symphurus 362 sundaicus, Brachirus 312 sunieri, Samariscus 261, 263* surinamensis, Pleuronectes 160 suyeni, Cynoglossus 342 Piscium Catalogus, Part Otolithi piscium, Vol. 2 swinhonis, Pseudorhombus 122 Syacium 11, 34, 38, 42, 44, 104, 135, 145, 158, 200 † dominicensis 15, 20, 22, 136, 139, 140* gunteri 136, 138, 139* longidorsale 136 micrurum 11, 135, 136, 137* ovale 55, 56, 136, 137, 138, 139*, 158, 200 papillosum 136, 137, 138*, 140 † syacioides 11, 17, 20, 25, 136, 140, 141* † syacioides, (Pleuronectidarum) 17, 140 † syacioides, Syacium 11, 17, 20, 25, 136, 140, 141* Symboulichthys 157 Symphurus 8, 10, 22, 36, 40, 42, 51, 338, 339, 342, 359, 360, 361 arabicus 362 arawak 362 atramentatus 362, 365, 366* atricaudus 18, 22, 52, 361, 362, 364, 364* australis 362 bergi 362 callopterus 362 caribbeanus 362 chabanaudi 362*, 363 civitatus 362, 364, 364* diabolicus 362 diomedianus 362 elongatus 362*, 363 fallax 362 fasciolaris 362 fuscus 362 gilesi 360, 362, 366*, 367 ginsburgi 362 gorgonae 362 holothuriae 362 jenynsi 362 kyaropterygium 362 leei 362, 364, 364* ligulatus 362 lubbocki 362 luzonensis 362 macrophthalmus 362 maldiviensis 362 marginatus 362 marmoratus 362 melanurus 362 melasmatotheca 362 meridionalis 362 microlepis 362 minor 362 nebulosus 362 nigrescens 19, 22, 26, 360, 362, 367, 367* normani 362 novemfasciatus 362 ocellatus 362 oculellus 362, 364, 364* oligomerus 362 ommaspilus 362 orientalis 362, 366, 366* paitensis 362 parvus 362 pelicanus 362 piger 362 plagiusa 362*, 363 plagusia 362, 362* 390 prolatinaris 362 pterospilotus 362 pusillus 362 regani 362 reticulatus 362 rhytisma 362 sayademalhensis 362 schultzi 362 septemstriatus 362, 366, 366* strictus 362 sumptuosus 362 tesselatus 362 trewavasae 362, 363, 363*, 364 trifasciatus 362 undatus 362 undecimplerus 362 urospilos 362 variegatus 362 varius 362 vittatus 362 williamsi 362, 365, 366* woodmasoni 362 Synaptura 35, 44, 45, 269, 306, 308 albomaculata 308*, 309 cadenati 308 commersoniana 18, 308, 308* lusitanica 306, 308, 309, 309* marginata 308 Synapturichthys 296 synapturoides, Zebrias 321, 322, 322* Synclidopus 324, 326 T taedifer, Bascanius 176 Taeniopsetta 38, 104, 165, 187 † dorsolobata 15, 21, 188, 189* ocellata 187, 188* radula 187, 188, 188* taeniopterus, Perissias 192 taivanus, Spinirhombus 126 taiwanensis, Parabothus 162 Tanakius 210, 223 kitaharae 223, 224, 225* tapeinosoma, Arnoglossus 167, 168, 176, 176*, 177 tapirina, Rhombosolea 47*, 52, 53, 55*, 253, 254, 256* Tapirisolea 68 Taratretis 62, 65, 70 derwentensis 70 Tarphops 19, 27, 38, 45, 104, 124, 134 elegans 135 oligolepis 134*, 135 † taureri, Arnoglossus 16, 17, 18, 21, 24, 25, 168, 170, 172, 173* † taureri, Solea 17, 172 † temputulensis, (Pleuronectidarum) 17 tenuirastrum, Pseudorhombus 125, 132, 132*, 133 tenuis, Areliscus 353 tenuis, Arnoglossus 168 tenuis, Peltorhamphus 19, 22, 27, 334, 336, 338* tenuis, (Pleuronectiformorum) 195 † tenuis, Solea 17, 18, 195 teophila, Quenselia 292*, 293 Tephrinectes 27, 28, 29, 33, 34, 38, 40, 44, 53, 62, 63, 66, 104, 105 sinensis 63, 64* Teratorhombus 124 tesselatus, Symphurus 362 tetrophthalmus, Lioglossina 113, 114, 114* texae, Nodogymnus 278, 279* † texana, Eosolea 17 texturatus, Aseraggodes 325 thompsoni, Apsetta 254 thori, Arnoglossus 168, 169, 171* Thyris 197 Thysanopsetta 34, 38, 40, 42, 45, 104, 105, 205, 206, 208 naresi 206, 206* tosana, Psettina 186 Tosarhombus 104, 199, 203 octoculatus 203 Trachypterophrys 207 † transitus, Cyclopsetta 17, 20, 22, 143, 145* trewavasae, Symphurus 362, 363, 363*, 364 Trichobrachirus 312 trichodactylus, Pleuronectes 290 trichodactylus, Solea 312 tricholepis, Achiropsetta 210 Trichopsetta 38, 104, 105, 189, 190, 191, 192 caribbaea 190 melasma 190, 191* orbisculus 190 ventralis 46*, 190, 191* trichospilus, Achirus 273 tricirrhatus, Bothus 158 trifasciatus, Symphurus 362 trigrammus, Cynoglossus 342, 348, 349* Trinectes 8, 269, 270, 273 fimbriatus 271 fluviatilis 271 fonsecensis 271, 272, 272* inscriptus 271 maculatus 270, 271, 271* microphthalmus 271 paulistanus 271, 272* triocellatus, Paralichthys 116 triocellatus, Pseudorhombus 125, 131, 132, 133, 133* triocellatus, Samariscus 52, 261, 262, 263* triophthalma, Solea 297, 298, 299* tropicus, Paralichthys 116, 119, 119* trulla, Plagusia 344 Trulla 340, 341, 342, 348 tshusanensis, Cynoglossus 353 tuberculatus, Pleuronectes 91 tubifera, Solea 318 tudori, Ammotretis 69, 69* tungkongensis, Laeops 193 turbot, Pleuronectes 91 Typhlachirus 269, 316, 323 lipophthalmus 323 sorsogonensis 323 U uhleri, Citharichthys 147 ui, Engyprosopon 19, 135 ui, Scaeops 204 umborsus, Platichthys 240 uncinata, Solea 69 Schwarzhans: Pleuronectiformes 391 undatus, Symphurus 362 undecimplerus, Symphurus 362 unicolor, Cynoglossus 342, 350*, 351 unicolor, Soleotalpa 280 unicornis, Citharichthys 152 unimaculatus, Rhombus 103 uniocellatus, Pleuronectes 103 Uropsetta 114 urospilos, Symphurus 362 Usinostia 340 V † validus, Samaris 17, 21, 27, 259, 260* Vanstraelenia 35, 269, 280, 281, 302, 305 chirophthalma 303, 304, 304* insignis 303, 304, 304* † varians, Citharichthys 17 variegata, Laeops 193 variegata, Psettina 186 variegatus, Mirochirus 18, 19, 21, 24, 25, 281, 282, 282*, 283, 284, 286, 288 variegatus, Symphurus 362 variegatus, Verasper 244, 244* varius, Symphurus 362 vaynei, Poecilopsetta 267 Velifracta 63 ventralis, Trichopsetta 46*, 190, 191* ventrocellatus, Cephalopsetta 135 Veraequa 246 Verasper 34, 210, 243, 245 moseri 243, 244 variegatus 244, 244* Verecundum 111 versicolor, Cynoglossus 353 verticalis, Pleuronichthys 247, 249, 249* vetulus, Parophrys 19, 21, 47*, 232, 233* victoriae, Pleuronectes 254 villosa, Brachirus 312 violaceus, Parabothus 162 vittatus, Symphurus 362 vorax, Paralichthys 116 vorax, Pseudorhombus 119 vulgaris, Hippoglossus 213 vulgaris, Limanda 227 vulgaris, Platessa 235 vulgaris, Solea 19, 296, 300 † vulsus, Pleuronectes 17 W waikyai, Arnoglossus 132 waitei, Arnoglossus 168, 176*, 177 wandersi, Cynoglossus 342 † weileri, Sebastes 17, 82 † weileri, (Bothidarum) 17, 82 † weinfurteri, Pseudorhombus 17, 18, 20, 25, 125, 133, 133* whiffiagonis, Lepidorhombus 19, 20, 24, 46*, 92, 93, 94*, 95, 98, 99 whitakeri, Aseraggodes 325 Whitleyia 310 † wienrichi, Microchirus 17, 21, 24, 283, 286, 287, 288, 289* williamsi, Symphurus 362, 365, 366* Piscium Catalogus, Part Otolithi piscium, Vol. 2 williamsoni, Nodogymnus 278 wittei, Microchirus 282, 292 wolffii, Rhombus 122 woodmasoni, Symphurus 362 woolmani, Paralichthys 116 X xanthosticta, Brachypleura 87 xanthostigma, Citharichthys 19 xanthostigma, Orthopsetta 20, 149, 151, 151* xenandrus, Engyprosopon 201, 202, 202* xenicus, Parachirus 330 xenicus, Samariscus 261 Xenobuglossus 294 † xenosulcis, Brachypleura 17, 20, 26, 86, 87, 88, 89* Xystreurys 38, 104, 106, 111 liolepis 111, 112, 112* rasile 112, 113* Xystrias 212 Y yokohamae, Pseudopleuronectes 238, 239* ypsigrammus, Bothus 158 Z zachirus, Glyptocephalus 19, 21, 47*, 225, 226*, 227* zanzibarensis, Cynoglossus 342, 355, 355* zanzibarensis, Poecilopsetta 267, 268* zanzibarica, Brachirus 312 zebra, Zebrias 321, 322, 323* Zebrias 35, 45, 269, 316, 318, 320, 323 altipinnis 321, 321* annadalei 321 cancellatus 321, 322, 322* cochinensis 321 craticulus 321 fasciatus 321 keralensis 321 lucapensis 321 munroi 321 penescalaris 321 quagga 321, 322, 323* scalaris 321 synapturoides 321, 322, 322* zebra 321, 322, 323* zebrinus, Achirus 273 zerbrinus, Nodogymnus 278 Zeugopterus 10, 11, 34, 45, 89, 100 punctatus 19, 20, 24, 100*, 101 † rosenthalensis 17, 20, 23, 101, 101* Zevaia 282, 290, 291, 295 zonatus, Ammotretis 69 Piscium Catalogus ISSN 0724-9012 A continuing file of all recent and fossil fishes from a paleoichthyological point of view Part OTOLITHI PISCIUM vol. 1 A comparative morphological treatise of recent and fossil otoliths of the family Sciaenidae (Perciformes) by Werner SCHWARZHANS pp. 1-245, 406 figs., July 1993, ISBN 3-923871-70-8, DM 240,– ; now DM 120,– / ˜ 61,36. vol. 2 A comparative morphological treatise of recent and fossil otoliths of the of the order Pleuronectiformes by Werner SCHWARZHANS pp. 1-392, 1021 figs., April 1999, ISBN 3-931516-54-7, DM 150,– / ˜ 76,69. vol. 3 is in preparation and will deal with recent and fossil otoliths of the Gadiformes and Batrachoidiformes Further volumes are being envisaged and will be published in 2 to 3 year intervals, dealing with Ophidiiformes Beryciformes and Zeiformes Osmeriformes and Stomiformes Myctophiformes Trachinoidei and Notothenioidei For orders please contact Verlag Dr. Friedrich Pfeil P.O. Box 65 00 86, D-81214 München Tel. (089) 74 28 270 – Fax (089) 72 42 772 – E-Mail 100417.1722@compuserve.com Piscium catalogus is a continuing file of all recent and fossil fishes from a paleoichthyological point of view ISSN 0724-9012 ISBN 3-931516-54-7