zyxwvutsr zyxwvu zyx zyxwvu zyxwvut zyxw Antarctic Science 12 (3): 269-275 (2000) 0 British Antarctic Survey Printed in the United Kingdom Hypotheses on Southern Ocean peracarid evolution and radiation (Crustacea, Malacostraca) A. BRANDT ZooloGcal Institute and Zoologzcal Museum, University of Hamburg, Martin-Luther-King-Platz 3, 0-201 46 Hamburg, Germany abrandt@zoologie unz-hamburg de Abstract: A short summary of some the most important hypotheses on the evolution of Southern Ocean peracarid crustaceans and some of the potential reasons for the high biodiversity of this taxon is presented. Besides the knowledge of horizontal and vertical distribution patterns of Southern Ocean peracarids, the importance of the evolution of the notothenioid fishes on the evolution of the Peracarida is discussed. Key questions for a better understanding of evolutionary biology of Southern Ocean Peracarida are highlighted. zyxwvuts Received 5 October 1999, accepted 3 February 2000 Key words: evolution, Peracarida, Notothenioidei, Southern Ocean Dedicated to Martin m t e , one of the nicest persons the Antarctic ever saw! Introduction other regions? Did the evolution of the benthic or benthopelagicNotothenioideihave an influenceon the evolutionand biodiversity of the Peracarida or vice versa (Eastman & Grande 1989, Eastman & Clarke 1998)? The second part of thispaper presents someargumentsfor a hypothesissuggesting a possible link in the evolution of the AntarcticNotothenioidei and some peracarid crustacean taxa. The early separationfrom Gondwanaand subsequentisolation of Antarctica led to the evolution of its unique benthic fauna. Despite the Tertiary climatic deterioration a number of taxa radlated in the Southern Ocean, especially on the continental shelf. The occurrence of distinct extinction events and emergence of new adaptive zones made previously occupied niches available and provided opportunities for spectacular adaptive rahation within many Antarctic benthic taxa. The precise timing of these radiations and the zoogeographic origin of many taxa, however, is largely uncertain and phylogenetic analyses that can be used in biogeography are still scarce. The extinctionof many decapodcrustaceans in the Cenozoic (e.g.Crame 1993,Feldmann&Tshudy 1989,Feldmann 1990, Feldmann et ul. 1993) may have allowed the Peracarida to fill free ecological niches. This evolutionary success has led to the evolution of 76-88% levels of endemism within the Amphpoda and the Isopoda, and 62%, 59% and 5 1% within the Cumacea,the Tanaidacea,and the Mysidacea, respectively. Amphipoda are the most diverseperacaridtaxon in the Southern Ocean with more than 820 species @e Broyer & Jazdzewski 1993), followed by Isopoda with about 365 species while the other peracarid taxa comprise only between 55-123 species (Brandt 1999). However, our knowledge of the Peracarida is based largely on shelf and upper slope data. As with many other groups, abyssal faunas are very poorly known. For that reason the first part of t h s paper underlines the importance of intensified efforts in deep-sea sampling. Thereis alsomuch still to be learnt about thebasic community ecology of both shallow and deep water peracarids in the Southern Ocean. How are the abundant species and diverse peracarid communities organised? Are levels of interspecific competition and predation equivalent to those known from Aspects of the evolution, biology, and biodiversity of Southern Ocean Amphipoda and Isopoda zyxwvutsrqpo Some groups of the Isopoda have radiated in Antarctica (Brandt 1991,1992,Wagele 1989a, 1994),andamongstthese are the families Serolidaeand Arcturidae. The phylogenetically more ancient Arcturidae are characterized by a higher percentageof Antarctic species, whereas the phylogenetically derived ones, such as the genus Astacilla Cordiner, 1793, are not present in the Southern Ocean at all, but occur in warmer waters. More than 50% of all species of Antarcturus Zur Strassen, 1902, Chaetarcturus Brandt, 1990 and Parudolichiscus occur in the Antarctic, as do most species of DolichiscusRichardson, 1913 (12:5), while Cylindrarcturus Schultz, 1981, Fissarcturus Brandt, 1990, Globarcfurus Kussakin & Vassina, 1994, Lztarcturus Brandt, 1990, Tuberurcturus Brandt, 1990 and Oxyurcturus Brandt, 1990 are confined to the Southern Ocean. Phylogeneticanalysisrecently proved to be a powefil tool for biogeography. It has been demonstratedfor the Antarctic amphipodfamily Iphmediidae by Watling & Thurston (1 989) that the most primitive genera are dstributed outside of the Antarctic waters. These authors suggest that the progressive retraction of speciesfrom a former cosmopolitan distribution occurred before the thermal isolation of Antarctica. They suggest that a later radiation of this taxon in the Southern 269 Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X z 270 zyxwvutsr zyxwvuts zyxwvu A. BRANDT Ocean may have been linked to the onset of the oceanic cooling some 35 m.a. ago. Several Antarctic isopod shelf species tend to gigantism (Wagele 1992). Antarctic shelf species of the Arcturidae, Chaetiliidae,and Serolidaeare larger than their non-Antarctic relatives and have relatively larger eggs (compare also White 1970, 1975, 1984), indicating that the number of offspring might alsobe somewhatreduced in SouthernOceanPeracarida compared with boreal or tropical relatives. It is not known whether this also applies for the Southern Ocean deep sea species. Investigationsof the anatomyof the stomachsand functional morphologyofthe mouthparts, combinedwith analysesof the stomach contents, have revealed that many Antarctic Amphlpoda have specialized and some are necrophages. Some feed on sponges, some on cnidarians, bryozoans, holothurians, or also on carrion (e.g. Coleman 1989, 1991). The Arcturidae are passive filter feeders (Wagele 1987b), whilst the larvae of the Gnathiidae are blood-sucking ectoparasites (Wagele 1988),and the adults live in harems and do not feed. The Aegidae are ectoparasites of fish (Wagele 1988) some, like the Anthuridea and Serolidaeare predators, feeding often on polychaetes, and the Cirolanidae are predominantly scavengers (e.g. Wagele 1987a, 1995). Knowledge of peracarid diets and their biology is mainly restricted to shelf species. zyxwvutsrq zyxwvuts zyxwvu Vertical distribution The isopod families Arcturidae and Serolidae are speciose with 90 and 44 species, respectivelybut with few speciesin the deep sea. The isopod species of the suborder Asellota, with 185 species in the Southern Ocean, usually increase in importanceand speciesnumbers with depth @ah1 et ul. 1976) Total 20 1 8 6 4 6 15 4 1 2 1 19 45 4 32 Flabellifera Aegidae 12 Anuropidae 2 Anthuridea 14 Cirolanidae 10 Gnathiidae 4 Limnoriidae 2 Plakarthriidae 1 Protognathiidae 2 Serolidae 44 Sphaeromatidae 20 Valvifera Arcturidae Chaetiliidae Idoteidae Total 111 Total ~~ families 90 5 17 7 10 185 Table 11. Depth distribution (depth intervals = 0-1000 m, 1000-2000 m, etc.) of isopod families, which have at least five species in the Southern Ocean. zyxwvuts Table I. Number of species of Isopoda families (Asellota, Flabellifera, Valvifera) in the Southern Ocean and southern South America. Asellota Acanthaspidiidae Dendrotionidae Desmosomatidae Haploniscidae Holognathidae Ischnomesidae Janiridae Joeropsidae Katianiridae Macrostylidae Mesosignidae Munnidae Munnopsidae Nannoniscidae Paramunnidae Pleurocopidae Stenetriidae and comprisealmost half of all species of Isopoda reported for the SouthernOceanandsoutherntipof SouthAmerica (TableI). Most species of the Janiroidea, isopods of the suborder Asellota, become more abundant with depth, and some janiroidean families are even primarily deep-sea colonizers (Wagele 1989a, Wagele & Brandt 1992) (Table 11). Table I1 shows the occurrenceof species of Southern Ocean isopod families (only those which are represented with more than five species) within selected depth zones. It is obvious that althoughthe Arcturidaeand Serolidaewere mainly sampled in shallower depths on the shelf, some Archuidae were also recorded from deeper water (Kussakin& Vasina l997,1998a, 1998b, 1998~).Most of the other families were only sampled inshallower water. TliedeeprangeoftheParanthuridae isdue to the eurybathy of Leptanthuru glacialis Hodgson, 1910, which was recorded as deep as 5216 m. Some other families of the Asellota (shownin bold), especiallythe Acanthaspiddae and even more the Munnopsidae,are also speciose on the shelf (wheremost samples have been collected so far), but were also found in hgher numbers in the deep sea. The 20 deepest occurring Southern Ocean isopod species are listed in Table 111. Almost 30% of these belong to the Munnopsidae (shown in bold), for example Disconectes vanhoeffeni or the species of Storthyngura Vanhoffen, 1914. Figure 1 illustrates the general depth distribution of all Antarctic Isopoda sampled. 250 species were found between 0 and 500 m; below 500 m only 62 species have been recorded and with increasing depth the number of isopod species decreases, with an exception around 3000 m, where there is a slight increase. If we now compare the depth distribution of all Southern Ocean Isopoda with the depth hstribution of selectedtaxa, for exampleofthe families Arcturidae, Serolidae, Acanthaspidiidae, and Munnopsidae, it is clear that most 112 Arcturidae Serolidae Pararnunnidae Sphaeromatidae Paranthuridae Aegidae Idotheidae Pleurocopidae Cirolanidae Chaetiliidae Desmosomatidae Janiridae Haploniscidae Ischnomesidae Stenetriidae Munnidae Acanthaspidiidae 0 1000 5 9 2 9 2 20 I 17 10 1 8 8 1 7 6 1 (depth m) 2000 3000 4000 5000 6000 7000 7 5 5 5 4 1 1 1 1 2 5 2 1 3 1 1 1 5 5 8 1 3 5 14 11 1 1 1 3 1 1 1 1 1 4 1 1 Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X 1 1 1 1 1 zyx zyxwvutsr zyxwv 271 EVOLUTION IN PERACARID CRUSTACEA 250 * i 70 60 zyxwvutsr Table 111. The 20 isopod species with the deepest depth range in the Southern Ocean. Munnopsidae are bold. ~ 1 0 depth (m) selected deep-sea species 0 0 0 - 0 0 0 c v c 0 0 0 T ) 0 0 0 0 0 0 * t v 0 0 0 ) ~ 0 0 0 b 0 0 0 0 3 depth (m) Fig. 1. Depth distribution of Antarctic isopod species (illustrated in depth intervals of 500 m). families are of predominantly shallow water in the Southern Ocean (Fig. 2). However, the Munnopsidaeshow a somewhat different pattern; this family contains species of a much deeper occurrence. In the Arctic Ocean, species of the Munnopsidae were reported from both the Greenland shelf and the deep sea, with the deepest record of Purumunnopsis justi Svavarsson, 1988 between 3709-3970 m depth (Svavarsson et uf.1993). Although the bathymetric pattern seen in the Southern Ocean agrees with that foundin other oceans, it is based on rather few deep sea hauls. For how many other families is the depth range much broader and what might we expect to find if we intensify polar deep-sea research? Will we discover a higher number of Antarctic isopod species, if we intensify Disconectes vanhoeffeni Acanthasprdia curtrsprnosa Gobarcturns angelrkae Ilyarachna antarctica Acanthasprdra rolanthordea Zoromtrnna setifions Storthyngurafurcata Storthyngura eltaninae Storthyngura sepigia Acantharcturus longipleon Neoarcturtts vrnogradovae Neoarcturus cochlearrcornrs Betamorpha fuszyormis Betamorpha indentifirons Leptanthura glacialis Mesosignum antarcticum Haplomesus qitadrrspinosus Antennulonrscus ornatlts Acanthoserolis maryannae Stenehrum a c u t m 7216-7200 6850-7219 6766-7216 252-1000 5600-6070 59864134 5850-6770 5431-5449 5431-5449 5 45 0-5 4 80 5450-5480 4704-46 80 1102-5208 203 1-4980 50-5216 398 1-4038 5 10-41 50 3756-3839 3839 150-3397 biological sampling at greater depths in the Southern Ocean? Knowledge on population ecology is scarce Although limited data on Antarctic Peracarida are available (e.g. Brandt etaf. 1994,Brandt 1997, Svavarssonetal. 1993), we still do not know very much about the basic population ecology of shallow or deep water peracarids in the Southern Ocean. Recently, the post-marsupial development of two 250 60 50 k *All Isopoda Ci Arduridae ASerolidae I +Acanthaspidiidae Munnopsiaae - * 4 * * .*. lo/ i $ : * n A o s 0 n A & . i n : : + ; t* z zyxwvut 4 Fig. 2. Depth distribution of Antarctic isopod species in comparison to some selected families (Arcturidae, Serolidae, Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X 272 zyxwvuts zyxwv zyxwvutsrqp A. BRANDT common species of the Tanaidacea from the Beagle Channel (South America) was analysed and probable life-cycles were hypothesised(Schmidt 1999). Knowledgeofbasic community ecology such as competition, predation, etc., will help us to understand evolutionary processes and phylogenetic relationships, especially with respect to potential selective pressures. It has been argued that Decapoda and Peracarida, for example, have a variety of protective adaptations, which help to reduce predation and enablethesetaxa tocoexist with fishes (Wagele 1989b)pan-oceanically. Whilst one of the potential adaptations discussed is dwarfism, (which is most obvious among the Asellota), gigantismis known tobe a characteristic of many Antarctic Peracarida (e.g. Wagele 1992, White 1984). Larger species or species with a disadvantage, e.g. a spiny shape, are not an easy prey for fish. Colonization of habitats in which predators are rare or absent, for example caves or animals such as sponges ( e g Kunzmann 1996), could be a strategy to reduce predation as well. Camouflage by mimesis is probably quite a common general phenomenon that can also be seen in the Southern Ocean, especially with regard to the colourfid pigment patterns on the cuticle of some species and the spines, which can serve both as a camouflage in front of an uneven background, like algae or blyozoans, and also as a protection against potential predators. Most of the epibenthic Isopoda and Amphipoda are rather successful shelf taxa and probably experienced a radlation in the SouthernOcean since the Tertiaq : Serolidae (withbroad, spiny and acute epimers), Arcturidae (some with long spines on the dorsal side ofthe body or the pereopods),Iphimedlidae, Epimeriidae) (Wading & Thurston 1989, De Broyer & Jazdzewski 1993), are characterized by a distinctive spine pattern,which might serveas a protectionagainstfishpredators. In Lake Baikal the cottoid fishes radiated and so did several generaof gammaridean amphipods (Eastman & Clarke 1998). “Almost all of the processiferous Gammaroids of the world are concentrated in Lake Baikal. Just over half of the genera are conspicuously noted for dorsal body or cephalic projections........many of these bear dorsal spination on the body” (Barnard & Barnard 1983, cf. also Dybovsky 1874). That spines are successful defenses against predation can be deduced from the fact that fish species were found with encapsuled spines of peracarid crustaceans in their mouths (e.g. buccal granulomatosis, see Anders 1987, Anders et al. 1992). The Notothenioidei also experienced an adaptive radiation in the Tertialy (e.g. Clarke & Johnston 1996). It is known that Antarctic fish feed on peracarid crustaceans (besides other items) (Grohsler 1992),therefore one might suspect a link in the evolution of the Notothenioidei and some successful peracarid taxa which radiated. The hypothesis of a linked evolution ofPeracarida and fish for a longer evolutionary time is further substantiatedby the fact that these crustaceans serve as intermediate hosts for Acanthocephala or Trematoda Digenea, whose final host is fish (Zander 1997). These parasites are common and abundant in boreal and Arctic areas (e.g. S a e et al. 1998)and also occur in the Southern Ocean (Palm et al. 1998, Zdzitowiecki 1991, 1996, 1998),although zy Table IV. Relative percentage of crustacean prey of fish species around Elephant Island in winter (May-June 1986) (after Grohsler 1992). Species Dtssostrchus mawsonr Pleuragramma antarcticum Notothenra rossri marmorata Notothenra gibberfrons Norothenia coriiceps neglecta Notothenia larseni Notothenia kempi Notothenia nudrfions Trematomiis etileprdotus Trematomiis newnesi Pagothenra hansoni Champsocephahrs gtinnarr Chaenocephahis acerahis Psetidochaen. georgianus Chronodraco rastrospinosirs Cryodraco antarcticus Neopagetopsrs ionah Parachaenichthys charcoh Gymnodraco actihceps Racovrtzra glacialis Gertacea australis Lycodichthys antarcticus Ophthalmolyciis amberensis Miiraenolepis mrcrops Bathyrala maccainr Amphipoda Cumacea Isopoda Mysidacea Tanaidacea Euphausid Copepoda Crustacea 16.8 0.3 18.4 54.4 9.6 19.7 30.6 80.3 6.7 0 21.4 0.1 2.1 0 0 1.5 0 0 2.6 0 0.3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.3 5.4 5.3 1.1 6.4 3.4 6.0 0 57.2 0 0 0 0 0 0 0 0 0 0 4.7 2.4 2.0 30.5 51.7 0 0.1 1.3 09 2.7 0.5 0.1 6.7 0 0 0 55.6 0 0 0 0 10.1 0 0 0 3.1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5.4 1.9 64.4 4.7 21.1 35.8 24.5 0.7 40.0 62.5 0 93.2 4.3 76.3 72.8 0 94.7 0 0.1 0 6.4 0.4 0.1 0 0 0 3.5 0.8 2.0 0.2 0.9 16 08 0 0 0 0 18.2 11.6 0 9.1 0 63.5 90.2 46.0 2.1 0 0 0 0 0 45.5 0 4.7 0 14.0 2.1 79.9 65.2 84.2 0 92.3 2.3 0 12.0 51.5 0 0 0 0 0 0 0 0 2.3 0 0 0 Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X 0 0 12.5 0 0.1 2.7 0 2.5 7.7 0.6 2.9 0 9.1 0 8.2 0 8.0 1.1 z zyxwvu zyxw z zyxw zyxwvutsrq zyxwvutsrq EVOLUTION IN PERACARID CRUSTACEA the knowledgeofparasitic species occurring in fishes living at deeper parts of the shelves and the continental slope is limited (Zdzitowiecla 1998, di Prisco et al. 1998). Analyses of the stomach contents of fish sampled around Elephant Island in May/June of 1986 revealed a wide variety of prey malacostracan crustaceans (Grohsler 1992). The species found in the stomachs of the fishes were, besides undeterminable material, at least 34 species of Amphipoda, 25 species of Isopoda, nine species of Mysidacea together with Cumacea and Tanaidacea. A comparison ofthe relative percentage of prey items in the stomachsof the most frequent fish species revealed that some species took a hlgh proportion of krill, while others had ingested a high percentage of Peracarida (Table IV). For example, Dissostichus mawsoni Norman mainly fed on fish, but with regard to the crustaceanfooditems,mysids (Mysidetes posthon Holt & Tattersall, 1905,Antarctomysis maxima Holt & Tattersall, 1906, and Pseudomma sp.), and amphipods (Rhachotropissp.)dominated, whereasNotothenia nudij?ons, on the contrary, had almost only Peracarida, especially Amphipoda (mostly unidentified, but some belonging to the taxa Caprellidea, Stenothoidae, and Parepimeria) in their stomachs. In general, infaunal Cumacea and Tanaidacea were not found in fish, whose diets were oriented towards epibenthicor benthopelagic and motile species of Amphipoda, Isopoda, and Mysidacea (compare Grohsler 1992). Most of the identified isopods from the stomachs of the investigatedfish were either Cirolanidaeor Aegidae; these are species which do not possess spines. Most, but not all, of the Amphipoda from the list of Malacostraca ingested by the Notothenioidei around Elephant Island (Grohsler 1992) and identified were also spineless ones, like Hyperiidea (1 1.5%), Isaeidae (8.1%), Synopiidae (4.3%), Oedicerotidae (3.0%), Caprellidea (2.6%), Ischyroceridae (2.5%), and Eusiridae (1.2%). Even if the pelagic and spinelessHyperiidea and the Amphipoda indet are excluded from the calculations, a very crude estimate (at family level) indicates that 76% of the amphipods from the fish stomachs are non-spinous ones and 24% spinous, suggesting that the spinous species might have a selective advantage in not being preyed often as intensively as the spineless ones. Even if the relative percentage of all spinousAntarctic Amphipoda only accounts for about 25% it is worth noting that at least the Iphimediidae, which radiated, did not belong to the regular diets of the investigated fish species (Grohsler 1992). Thelong, acutespinesofthoseperacaridtaxawhchradiated might serve as a good passive arm when the animals bend down and feed, like Echiniphimedia hodgsoni, a species which is known to prefer sponges. These animals would usually be an easy prey for fishes while feeding, like species of Gnathiphimediaor Iphimediella, whch feed on bryozoans. Besides being well equipped with spines, some species also have polymorphcpigmentpatternson the cuticle,llkeEpimeria macrodonta or Ceratoserolis trilobitoides (Wagele 1986), 273 probably also for camouflage. Conclusions Maybe a selectivepressurefavoured the evolutionand radtation of spiny taxa at the same time as the radiation of the Notothenioidei began. This may have coincided with the Southern Ocean cooling in the Oligocene, some 38 m.y.a. “The rapid coolingand the onset of glaciationeradicated most of the Eocene fauna...,...evolution of antifreeze glycoproteins must have taken place by middle Miocene coolingat the latest. Pliocene warming may have stimulated radiation with some already established clades through provision of extensivenew coastal and shallow water habitats” (Clarke & Johnston 1996, p. 214). “Diversification of the emergmg notothenoid fauna was facilitated by the oceanographicand thermal isolation of Antarctica, by the increasing productivity of the Southern Ocean beginning about 22 Ma and by the absence of the nonnotothenioids” (Eastman & Clarke 1998, p. 15). For a better understanding of the evolutionary biology of Southern Ocean Peracarida, it is necessary to increase our knowledgeboth on SouthernOceanpopulationand community ecology and Antarctic deep sea biology! We must understand the present in order to explain the past, enabling us to answer such questions as: Is there a coincidence in time between the evolutionof the Notothenioidei and some peracarid taxa, ( e g some taxa ofAmphipoda,Isopoda)? In other words, did the evolution of the benthic or bentho-pelagic Notothenioidei have an influenceon the evolutionandbiodwersityofthe Antarctic Peracarida? zyxwvuts zyxwvut If we suppose that the evolution of the Peracarida and Notothenioidei is somehow related, is their evolution possibly linked to the thermal isolation of Antarctica and the oceanic cooling in the Oligocene, which might have favoured the radiation of some “preadapted’ taxa? Can we trace a change in the ocean current regimes with the Oligocene cooling (direction, velocity, etc.), which might have increased fine grain-sized sediments and favouredthe evolutionof infaunal taxa (e.g. tanaidaceans, cumaceans)? Has the increased ice extension (followed by annual or cyclic retreats) increased the presence of drop stones and thus the availability of hard substrate for sessile filter feeders in general, which might have thrived since then (e.g. at Kapp Norvegia since the Oligocene?) (cf. van Praet et al. 1990)? Are the filter-feeding Arcturidae (Isopoda) so successful in the Antarctic because of the high percentage of sessile suspension feeders? Serolid isopods primarily feed on polychaetes, but many Amphipod taxa are extremely specialized in their diets, Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X 274 zyxwvuts zyxwvu A. BRANDT zyxwvutsrq feeding on sponges,bryozoans, cnidarians, holothurians, all groups which thrive in the Southern Ocean or have speciated - is their extremely specialized diet just coincidence? Acknowledgements The steering committee of the SCAR Evolutionary Biology Group hndly invited the author to present a talk during the workshop in Curitiba, Brazil (12-15 May 1999), and the German Science Foundation supported the travel (Br 1121-15/1). Dr E. Fanta, Curitiba, lclndly organized the workshop. The author is most grateful to Dr W. Arntz, Dr G. Poore, ProfessorA. Clarke andespeciallyDrM.Thurston for critical comments on the manuscript; to Dr H.G. Andres for literatureon AmphipodafromLakeBaikd,andDrB. Hilbig for discussions. References DYBOWSKY, B.N. 1874. Beitrage zur naheren Kenntnis der im BaikalSee vorkommenden niederen K r e b s e aus der G r u p p e der Gammariden. Russian Entomological Society, St Petersburg: W. Besobrasoff, 1-190, 14 plates. EASTMAN, J.T. & GRANDE, L. 1989. Evolution of the Antarctic fish fauna with emphasis on the recent notothenioids. In CRAME, J.A., ed. Origins and evolution of the Antarctic biota. Geological Society Special Publication, 47, 241-252. EASTMAN, J.T. &CLARKE, A. 1998. Acomparison ofadaptive radiations of Antarctic fish with those of non-Antarctic fish. In DI PRISCO, G., PISANO,E. & CLARKE,A,, eds. 1998. Fishes of Antarctica: a biological overview. Milan: Springer, 3-26. FELDMANN, R.M. 1990. On impacts and extinction; biological solutions to biological problems. Journal of Palaeontology, 64, 15 1-154. FELDMANN, R.M. & TSHUDY, D.M. 1989. Evolutionary patterns in macrurous decapod crustaceans from Cretaceous to early Cenozoic rocks ofthe James Ross Island region, Antarctica. In CRAME, J.A., ed. Origins and evolution of the Antarctic biota. Geological Society Special Publication, 47, 183-195. FELDMANN, R.M., TSHUDY, D.M. & THOMSON, M.R.A. 1993. Late Cretaceous and Paleocene Decapod Crustaceans from James Ross Basin, Antarctic Peninsula. Journal of Palaeontology, 67, 1-41. GROHSLER, T . 1992. Nahrungsokologische Untersuchungen an antarktischen Fischen um Elephant Island unter besonderer Beriicksichtigung des Sudwinters. Mitteilungen ails dem Institutfiir Seefischerei. 47, 1-296. KUNZMANN, K. 1996. Associated fauna of selected sponges (Hexactinellida and Demospongiae) from the Weddell Sea, Antarctica. Berichte ziir Polarforschung, 210, 1-93. KUSSAKIN, O.G. & VASINA, G.S. 1997. Three new species ofArcturidae from the lower abyssal zone of Lorie and South Sandwich Trenches, West Antarctica (Crustacea: Isopoda: Valvifera). Zoosystematica Rossica, 5, 221-232. KUSSAKIN, O.G. & VASINA.G.S. 1998a. New bathyal and abyssal arcturids from the western Antarctic and subantarctic (Crustacea: Isopoda: Arcturidae). Zoosystematica Rossica, 7, 55-75. KUSSAKIN, O.G. & VASINA, G.S. 1998b. Two New species of isopod crustaceans of the genus Neoarcturus (Isopoda, Valvifera) from the Western Antarctic. Russian Journal ofMarine Biology, 24, 84-90. KUSSAKIN, O.G. & VASINA,G.S. 1998c. Antarcturusprinceps, a new species of Arcturidae (Crustacea, Isopoda, Valvifera) from Subantarctic deep-sea waters. Russian Journal of Marine Biology, 24, 394-397. [In Russian] M. & PLOTZ,J. 1998. The role of PALM,H.W., REIMANN, N., SPINDLER, the rock cod Notothenia coriiceps Richardson, 1844 in the life-cycle of Antarctic parasites. Polar Biology, 19,399-406. SCHMIDT, A. 1999. Die Tanaidaceenfauna des Beagle-Kanals und ihre Beziehiingen zur Fauna des antarktischen Festlandsockels. Diplomarbeit, Universitat Hamburg, 114 pp. [Unpublished] SUFKE, L., PIEPENBURG, D. & VONDORRIEN, C. 1998. Body size, seyratio and diet composition ofArctogadus glacialis (Peters, 1874) (Pisces. Gadidae) inthe Northeast Water Polynya (Greenland). PolarBiology, 20, 357-363. SVAVARSSON, J.O. S T R ~ M B EJR. -G0,. & BRATTEGARD, T. 1993. The deepsea asellote (Isopoda, Crustacea) fauna of the northern seas: species composition, distributional patterns and origin. Journal of Biogeography, 20, 537-555. VANPRAET, M., RICE,A.L. & THURSTON, M.H. 1990. Reproduction in two deep-sea anemones (Actiniaria); Phelliactis hertwigi and P . robusta. Progress in Oceanography, 24, 207-222. WAGELE, J.W. 1986. Polymorphism and Distribution of Ceratoserolis trilobitoides (Eights, 1833) (Crustacea, Isopoda) in the Weddell Sea and synonymy with C. cornuta (Studer, 1879). Polar Biology, 6, 127-1 37. zyxwvutsrqpon zyxwvuts zyxwvutsrqp ANDERS,K. 1987. Biologie van Tumor- und tumorahnlichen Krankheiten der Elbfische. Kiel: Verlag Heino Moller, 1-1 73. ANDERS, K. & M ~ L L EH. R , 1992. Atlas off;sh diseases i n the Wadden Sea. Berlin: Erich Schmidt Verlag, 65. BARNARD, J.L. & BARNARD, C.M. 1983. Freshwater Amphipoda of the World. I. Evolutionary patterns. Mount Vernon, VA: Hayfield Associates, 358 pp. BRANDT, A. 199 1. Zur Besiedlungsgeschichte des antarktischen Schelfes am Beispiel der Isopoda (Crustacea, Malacostraca). Berichte ziir Polarforschung, 98, 1-240. BRANDT, A. 1992. Origin of Antarctic Isopoda (Crustacea, Malacostraca). Marine Biology, 113,41 5-423. BRANDT, A. 1997. Redescription of Munnopsurus giganteus (Sars, 1879) (Isopoda, Asellota, Eurycopidae). Crustaceana, 70,288-303. BRANDT, A., SVAVARSSON, J. & BRATTEGARD, T . 1994. Eurycope brevirostris (Isopoda; Asellota) from the deep Arctic Ocean; redescription, postmarsupial development, and reproductive pattern. Sarsia, 79, 127-143. BRANDT, A. 1999. On the origin and evolution of Antarctic Peracarida (Crustacea, Malacostraca). ScienciaMarina, 63(Suppl. l), 261-274. CLARKE, A. & JOHNSTON, I.A. 1996. Evolution and adaptive radiation of Antarctic fishes. Trends in Ecology andEvoltition, 11, 212-218. COLEMAN, C . O . 1 9 8 9 . On the nutrition of two Antarctic Acanthonotozomatidae (Crustacea, Amphipoda). Gut contents and functional morphology of mouthparts. Polar Biology, 9, 287-294. COLEMAN, C 0. 1991. Comparative fore-gut morphology of Antarctic Amhipoda (Crustacea) adapted t o different food sources. Hydrobiology, 223, 1-9. CRAME, A. 1993. Latitudinal range fluctuations in the marine realm through geological time. Trends in Ecology and Evolution, 8, 162-166. DAHL,E., LAUBIER, L., SIBUET, M. & STROMBERG, J.O. 1976. Some quantitative results on benthic communities of the deep Norwegian Sea. Astarte, 5 , 61-79. DE BROYER, C. & JAZDZEWSK, K. 1993. Contribution to the marine biodiversity inventory. A checklist of the Amphipoda (Crustacea) of the Southern Ocean. Documents de Travail de L 'Institiit royal des Sciences naturelles de Belgique, 73, 1-154. DIPRISCO, G., PISANO, E. &CLARKE, A. eds. 1998. FishesofAntarctica: a biological overview. Heidelberg: Springer Verlag, 1-363. zyxwvutsrqp Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X z zyxwvutsrqpon zyxwvutsrqponm zyxwv EVOLUTION IN PERACARID CRUSTACEA WAGELE, J.W. 1987a. The feeding mechanism of Antarcturus and a redescription ofA. spinacoronatus Schultz, 1978 (Crustacea: Isopoda: Valvifera). Philosophical Transactions oftheRoyalSociety, London, B316, 429-458. WAGELE, J.W. 1987b. On the reproductive biology of Ceratoserolis trilobitoides (Crustacea, Isopoda): Latitudinal variation of fecundity and embryonic development. Polar Biology, 7, 11-24. WAGELE, J.W. 1988. Aspects of the life cycle of the Antarctic fish parasite Gnathia calva Vanhoffen (Crustacea: Isopoda). Polar Bi OlOgy, 8, 2 87-2 9 1. WAGELE, J.W. 1989a. Evolution und phylogenetisches System der Isopoda. Stand der Forschung und neue Erkenntnisse. Zoologica, Stuttgart, 1-262. WAGELE, J. W. 1989b. On the influence of fishes on the evolution of benthic crustaceans. Zeitschrifi fur Zoologische Systematik und Evolutionsforschung. 27, 297-309. WAGELE, J.W. 1992. Systematische Untersuchungen an Tieren polarer Regionen. Benthosokologie im Sudpolarmeer und die Lebensweise und Evolution antarktischer Isopoda (Crustacea: Peracarida). Verhandlungen der Deutschen Zoologischen Gesellschaft, 85.2, 2 5 9-270. WAGELE, J.W. 1994. Notes on Antarctic and South American Serolidae (Crustacea, Isopoda) with remarks on the phylogenetic biogeography and description of new genera. Zoologische Jahrbiicher Systematik, 121, 3-69. WAGELE, J.W. 1995, Die Antarktis - erdgeschichtlichtliche Brutstatte I. & HEMPEL, G., eds. Biologie der fur exotische Krebse. In HEMPEL, Polarmeere. Erlebnisse und Ergebnisse. Jena: Gustav Fischer Verlag, 26 7-2 74. 275 WAGELE, J.W. & BRANDT, A. 1992. Aspects of the biogeography and biology of Antarctic isopods (Crustacea). In GALLARDO, V.A., FERRETTI, 0.& MOYANO, H.J., eds. Oceanogra3a en Antartide. ENEA Progretto Antartide Italia, 417-420. WATLING, L. & THURSTON, M. 1989. Antarctica as an evolutionary incubator: evidence from the cladistic biogeography ofthe amphipod family Iphimediidae. In CRAME, J.A., ed. Origins and evolution of the Antarctic biota. Geological Society Special Publication, 47, 297-313. WHITE,M.G. 1970. Aspects of the breeding biology of Glyptonotus antarcticus (Eights) (Crustacea, Isopoda) at Signy Island, South Orkney Islands. In HOLDGATE, M.W., ed. Antarctic ecology, vol 1 London: Academic Press, 279-285. WHITE,M.G. 1975. Oxygen consumption andnitrogen excretion by the giant Antarctic isopod Glyptonotiis antarcticus, Eights in relation to cold-adapted metabolism in marine polar poikilotherms. Proceedings Yh European Marine Biological Symposium, 1975, Aberdeen: University Press, 707-724. WHITE,M.G. 1984. Marine benthos. In LAWS,R.M., ed. Antarctic Ecology, vol. 2. London: Academic Press, 421-461. ZANDER, C.D. 1997. Parasit-Wirt-Be=iehungen. Heidelberg: Springer Verlag, 184 pp. ZDZITOWIECKI, K. 199 1 . Antarctic Acanthocephala. In WAGELE, J.W & SIEG,J., eds. Synopses of the Antarctic benthos. Koenigstein: Koeltz, 1-1 16. ZDZITOWIECKI, K . 1996. Acanthocephala in fish from the Weddell Sea (Antarctic). Acta Parasitologica Polonica. 41, 199-203. ZDZITOWIECKI, K. 1998. Diversity of Digenea, parasites of fishes in various areas ofthe Antarctic. In D I PRISCO, G., PISANO, E. & CLARKE, A,, eds. Fishes of Antarctica: a biological overview. Heidelberg: Springer Verlag, 87-94. zyxwvutsrqpo zyxwvutsrqpon Downloaded from https://www.cambridge.org/core. IP address: 207.241.231.83, on 26 Jul 2018 at 02:26:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S095410200000033X