Zootaxa 236: 1-8 (2003) www.mapress.com/zootaxa/ ISSN 1175-5326 (print edition) Copyright © 2003 Magnolia Press ISSN 1175-5334 (online edition) ZOOTAXA Two new species of the genus Chlopsis (Teleostei: Anguilliformes: Chlopsidae) from the Southwestern Pacific KENNETH A. TIGHE1 & JOHN E. McCOSKER2 1 Department of Systematic Biology, Smithsonian Institution, P.O. 37012, Washington, DC 20013-7012 (email: tighe.ken@nmnh.si.edu) 2 Department of Aquatic Biology, California Academy of Sciences, San Francisco, California 94118 (email: jmccosker@calacademy.org) Abstract Chlopsis slusserorum, from Fiji and the Solomon Islands, and Chlopsis bidentatus, from Fiji and New Caledonia, two new deepwater species of false moray eels belonging to the family Chlopsidae, are described and illustrated. Chlopsis slusserorum is distinguished from all other chlopsids by its combination of high vertebral count and distinctive pigmentation. Chlopsis bidentatus is distinguished by the combination of bicolored pigmentation, dorsal origin slightly behind gill opening and anteriorly biserial vomerine dentition. Key words: Eels, Chlopsis slusserorum, Chlopsis bidentatus, new species, Fiji, Solomon Islands Introduction The most recent reviews of the genus Chlopsis were those of Lavenberg (1988) and Smith (1989). Lavenberg (1988) recognized four species from the eastern Pacific: C. apterus (Beebe and Tee Van, 1938), C. bicollaris (Myers and Wade, 1941), C. kazuko Lavenberg, 1988 and C. longidens (Garman, 1899). Although C. longidens is based on a leptocephalus and is probably the larva of one of the other species, Lavenberg (1988) did not conclusively identify this species with an adult. However, he did indicate that it was likely that it was the larva of C. bicollaris. Smith (1989) recognized six species: C. apterus, C. bicollaris and C. kazuko from the eastern tropical Pacific, C. olokun (Robins and Robins, 1966) from the eastern tropical Atlantic, C. bicolor Rafinesque, 1810 from the Mediterranean and Atlantic and C. dentatus (Seale, 1917) from the tropical western Atlantic, western Indian and western Pacific Oceans. Accepted: 26 June 2003; published: 9 July 2003 1 236 ZOOTAXA 236 Recent collecting in the Central Pacific by ORSTROM yielded three specimens of two undescribed species of this family. One additional specimen of one of these species from the Australian Museum had been previously misidentified as C. dentatus and was the basis for including the western Pacific Ocean in the distribution of that species by Smith (1989). Methods and materials General methods for morphometric and meristic data for this study are given in Böhlke (1989). All measurements are given as a proportion of the total length (TL) except for subunits of the head which are presented as proportions of the head length (HL). Vertebral and fin ray counts were taken from radiographs. Total vertebral counts are of all elements including the hypural. Preanal and predorsal vertebral counts were taken using the definitions of Böhlke (1982). Precaudal vertebral counts include all elements anterior to the first vertebra that has a distinct, posteriorly directed haemal spine. Meristic and morphometric data for the type series are presented with the values of the holotype first and values of the paratype given in brackets. The holotypes of both species were damaged in the region of the gill opening on the left side. For this reason, figures were taken from the right side and then reversed for publication. The specimens are deposited at the Museum National d'Histoire Naturelle, Paris (MNHN) and the Australian Museum, Sydney (AMS). Chlopsis slusserorum sp. nov. (Figs. 1, 2, 3A, 4) Holotype: MNHM 2001-1079, 141 mm total length, Fiji, Somo-Somo Stait, 16º 27' S, 179º 35.4' W, depth 426-487 m, captured with Waren dredge, Campagne Bordau 1, Station DW 1393, 23 February 1999. Paratype: AMS I.17284-001, 86 mm TL, Solomon Islands, Malaita Island, S of Aoki, 8º 24' S, 160º 35' E, depth ca. 366 m, collector: P. Coleman, 27 August 1973. FIGURE 1. Holotype of Chlopsis slusserorum, MNHN 2001-1079, 141 mm TL; Somo-Somo Strait, Fiji. Diagnosis. The high vertebral count combined with the distinctive pigmentation differentiates this species from all others in the genus Chlopsis. Description. Total vertebrae 138 (138), predorsal vertebrae 12 (12), preanal vertebrae 40 (41), precaudal vertebrae 60 (56). Proportions as percent of TL: predorsal length 13.2 (13.8), preanal length 33.5 (34.2), head length 11.1 (12.1), depth at anus 2.9 (2.6). Propor2 © 2003 Magnolia Press TIGHE & McCOSKER tions as percent of head length: eye diameter 13.4 (13.5), interorbital width 12.1 (10.6), snout length 22.9 (22.1), tip of snout to rictus of jaw 35.0 (33.6). Body moderately elongate, slightly compressed. Dorsal fin begins slightly more than one eye diameter posterior to gill opening (Fig. 2). Head moderate in length, relatively deep. Snout relatively broad. Gape short, rictus below posterior margin of eye. Anterior nostril tubular, slightly behind tip of snout, directed anterolaterally. Posterior nostril a postero-ventrally directed low tubular opening (not covered by a flap) on lip in front of vertical from middle of eye. FIGURE 2. Head of holotype of Chlopsis slusserorum, MNHN 2001-1079. Lateral line on body absent except for one pore in branchial region, anterior to the gill opening (Fig. 2). Supraorbital pores three: first (ethmoidal) at anteroventral tip of snout, second anteromedial to base of anterior nostril, and last above and behind anterior nostril. Infraorbital pores four: first just posterior to anterior nostril, second midway between anterior and posterior nostrils, third just behind posterior nostril, and last below posterior edge of eye. Preoperculomandibular pores five; first near tip of lower jaw, second below interspace between anterior nostril and infraorbital pore 1, third below interspace between infraorbital pores 1 and 2, forth below posterior nostril, and last below and slightly posterior to infraorbital pore 4. Maxillary teeth (Fig. 3A) conical, slightly recurved, in 2 irregular rows; inner row larger than outer, a total of 30-31 teeth in the inner row. Intermaxillary teeth conical, slightly recurved, with approximately 20 teeth in a round patch; median and posterior teeth somewhat enlarged. Mandibular teeth like those of the maxilla, except in 2-3 irregular rows anteriorly, reducing to 2 rows posteriorly, with 25-27 teeth in the inner row. Vomerine teeth similar in shape and size to enlarged inner rows of maxillary and mandibular teeth; in two longitudinal series, converging near the end of the tooth rows into a single, irregular median row of small teeth reaching slightly behind the maxillary tooth rows; total of 20-21 teeth in each longitudinal series and 2 small teeth in the median row. Base color of body light tan; dorso-lateral surface of body overlaid with a series of circa 30-35 dark brown blotches (Figs. 1 and 4); blotches either do not extend to the dorsal surface (anterior to dorsal fin origin or near tail) or only weakly extend to the dorsal fin TWO NEW CHLOPSIS SPECIES © 2003 Magnolia Press 3 ZOOTAXA 236 ZOOTAXA 236 base (which is lightly pigmented for most of its length); blotches do not line up in pairs with blotches on other side of body (Fig. 4). FIGURE 3. A. Upper and lower jaws of holotype of Chlopsis slusserorum, MNHN 2001-1079. B: Upper and lower jaws of holotype of Chlopsis bidentatus, MNHN 2001-1080. Etymology. We are pleased to name this distinctive eel in honor of Marion and Willis Slusser, in recognition of their keen interest in natural history and generous support of research and education. Remarks. Chlopsis slusserorum is very similar in pigment pattern to C. dentatus from the western Atlantic and western Indian Oceans, which resulted in the paratype being misidentified as C. dentatus by Smith (1989). However, the higher vertebral count (138 versus 116-124) clearly separates the two species. All other species of the genus Chlopsis have either relatively uniform coloration or are distinctly bicolored. 4 © 2003 Magnolia Press TIGHE & McCOSKER Nearly all of the description is based only on the holotype due to the small size and poor condition of the paratype. The paratype apparently became dessicated some time in the past, and the position and number of pores could not be determined. In addition, the lower jaw was badly broken and teeth were missing. Therefore, tooth counts could only be approximated. However, we believe the two specimens to be conspecific, given the similarity in pigment pattern and vertebral numbers. FIGURE 4. Dorsal (A) and left lateral (B) views of the mid-body of holotype of Chlopsis slusserorum, MNHN 2001-1079, showing distinctive lateral pigment blotches. Chlopsis bidentatus sp. nov. (Figs. 1, 2, 3B) Holotype: MNHN 2001-1080, 167 mm total length, New Caledonia, 23º 48' S, 168º 17' E, depth 444-503 m, captured with beam trawl, Campagne Bathus 3, Station CP 814, 28 November 1993. Paratype: MNHN 2001-1078, 132 mm TL, Fiji, Somo-Somo Stait, 16E 27í S, 179E 34.8' W, depth 300-370 m, captured with Waren dredge, Campagne Bordau 1, Station DW 1454, 04 March 1999. FIGURE 5. Holotype of Chlopsis bidentatus, MNHN 2001-1080, 167 mm TL; New Caledonia Diagnosis. Distinguished from all other members of the genus Chlopsis by the combination of the following characters: pigmentation bicolored, dorsal origin approximately TWO NEW CHLOPSIS SPECIES © 2003 Magnolia Press 5 ZOOTAXA 236 ZOOTAXA 236 one eye-diameter behind gill opening, and vomerine dentition in two biserial rows anteriorly. Description. Total vertebrae 125 (128), predorsal vertebrae 11 (11), preanal vertebrae 31 (32), precaudal vertebrae 42 (41). Proportions as percent of TL: predorsal length 13.2 (13.8), preanal length 33.5 (34.2), head length 11.1 (10.3), depth at anus 2.9 (2.6). Proportions as percent of head length: eye diameter 13.4 (13.5), interorbital width 12.1 (10.6), snout length 22.9 (22.1), tip of snout to rictus of jaw 35.0 (33.6). Body moderately elongate, slightly compressed. Dorsal fin begins slightly more than one eye diameter posterior to gill opening (Fig. 6). Head moderate in length, relatively deep. Snout relatively broad. Gape short, rictus at posterior margin of eye. Anterior nostril tubular, slightly behind tip of snout, directed anterolaterally. Posterior nostril a posteroventrally directed low tubular opening (covered by a flap) on lip in front of vertical from middle of eye. FIGURE 6. Head of holotype of Chlopsis bidentatus, MNHN 2001-1080. Lateral line on body absent except for one pore in branchial region, anterior to the gill opening (Fig. 6). Supraorbital pores three: first (ethmoidal) at anteroventral tip of snout, second anteromedial to base of anterior nostril, and last above and behind anterior nostril. Infraorbital pores four: first just behind anterior nostril, second midway between anterior and posterior nostrils, third below posterior nostril, and last below middle of eye. Preoperculomandibular pores five; first near tip of lower jaw, second below interspace between anterior nostril and infraorbital pore 1, third below interspace between infraorbital pores 1 and 2, forth below posterior nostril, and last below and slightly posterior to infraorbital pore 4. Maxillary teeth (Fig. 3B) conical, slightly recurved, in 2-3 irregular rows, increasing in size from outer to inner, a total of 18-20 teeth in the inner row. Intermaxillary teeth conical, slightly recurved, with approximately 20 teeth in a round patch (more teeth can be seen on a radiograph of the holotype, but only about 20 penetrate through the tissue in the mouth). Mandibular teeth like those of the maxilla, except in 4-5 irregular rows anteriorly, reducing to 2-3 posteriorly, with 16-20 teeth in the inner row. Vomerine dentition shorter and stouter, slightly compressed, in two longitudinal series, weakly biserial anteriorly and uniserial posteriorly, 15-16 slightly larger teeth in the longer inner row, and 7-8 smaller 6 © 2003 Magnolia Press TIGHE & McCOSKER teeth in the outer biserial row. Dentition of paratype very similar in both counts and arrangement to those of the holotype. Color of body light brown above and distinctly white ventrally; ventral light area strongly demarcated from the darker dorsum of the snout, starting on unpigmented anterior nostril, continuing back above posterior nostril to ventral margin of eye; tip of lower jaw also pigmented (Fig. 6); posterior to eye, dorsal edge of ventral light area becomes more irregular, but extends dorsally to the gill opening; ventral light area then tapers to base of anal fin slightly behind anus, but continues along base of anal fin for approximately 2/3 of body length; anal fin remains unpigmented to near tip of tail; ventral base of caudal fin and posterior portion of anal fin base much darker than rest of body. Etymology. The name bidentatus is from the Latin bi (two) and dentatus (toothed) in reference to the distinctive vomerine dentition. Remarks. Chlopsis bidentatus is similar in overall appearance to several other members of the genus Chlopsis. Chlopsis apterus, C. bicollaris and C. kazuko, all from the eastern Pacific Ocean, are all also bicolored. The posterior origin of the dorsal fin (at least one eye diameter behind the gill opening) separates C. bidentatus from C. bicollaris and C. kazuko. Chlopsis apterus, which also has the dorsal origin behind the gill opening, has a higher vertebral number (125-128 in C. bidentatus versus 134-140 in C. apterus). Chlopsis bicolor, from the Atlantic Ocean, is very similar in both meristics and morphometrics, as well as in its coloration. Several aspects of the dentition of C. bidentatus, especially the anterior biserial vomerine dentition, clearly separate C. bidentatus from C. bicolor. All other species in the genus Chlopsis can be distinguished from C. bidentatus by coloration. Chlopsis olokun, from the eastern Atlantic, is a fairly uniform tan or gray color, while C. dentatus (from the Atlantic and Indian Oceans) and C. slusserorum (described herein from the Pacific) have banded, blotched or mottled coloration. In the past, differences in vomerine dentition like that described for C. bidentatus would result in the description of a new genus; for example, Robinsia in Böhlke and Smith (1967), and Boehlkenchelys in Tighe (1992). However, due to the overall morphological similarity of this species to that of others in the genus, and the lack of any hypothesis of relationships within the family, we have taken the conservative approach of describing it within the genus Chlopsis. Relationships within the family are being studied by the senior author, and may later determine whether or not this is the correct decision. Acknowledgments We would like to thank Bernard Séret and Patrice Pruvost (MNHN), and Mark McGrouther (AMS) for making the specimens available. We would also like to thank G. David Johnson and David G. Smith for reviewing the manuscript, and Dong Lin and Isabella Kirkland for preparing Figures 1 and 4, respectively. The junior author's participation in this project resulted from his tenure as a Visiting Professor at the Museum National d'Histoire Naturelle, Paris. TWO NEW CHLOPSIS SPECIES © 2003 Magnolia Press 7 ZOOTAXA 236 ZOOTAXA References 236 Böhlke, E.B. (1982) Vertebral formulae for type specimens of eels (Pisces: Anguilliformes). Proceedings of the Academy of Natural Sciences, Philadelphia, 134, 31-49. Böhlke, E.B. (1989) Methods and terminology. In Böhlke, E. B., (ed.), Fishes of the Western North Atlantic. Memoir of the Sears Foundation for Marine Research, No. 1, Part 9, pp. 1-7. Böhlke, J.E. & D.G. Smith. (1967) A new xenocongrid eel from the western Indian and western Atlantic Oceans. Notulae Naturae, No. 406, 9 pp. Lavenberg, R.J. (1988) Chlopsid eels of the eastern Pacific with a new species and descriptions of larval forms. Bulletin of Marine Science, 42(2), 256-264. Smith, D.G. (1989) Family Chlopsidae. In Böhlke, E. B., (ed.), Fishes of the Western North Atlantic. Memoir of the Sears Foundation for Marine Research, No. 1, Part 9, pp. 72-97. Tighe, K.A. (1992) Boehlkenchelys longidentata, a new genus and species of chlopsid eel (Teleostei: Anguilliformes) from the Indo-West Pacific region. Proceedings of the Biological Society of Washington, 105(1), 19-22. 8 © 2003 Magnolia Press TIGHE & McCOSKER