PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 116(3):692-698. 2003. A new Pseudocetopsis species (Siluriformes: Cetopsidae) from Suriname and French Guiana Richard P. Vari, Carl J. Ferraris, Jr., and Philippe Keith — (RPV) Department of Systematic Biology Fishes, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560-0159, U.S.A.; — (CJF) Research Associate, Department of Systematic Biology Fishes, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560-0159, U.S.A.; (PK) Museum National d'Histoire Naturelle, Laboratoire d'ichtyologie, 43 rue Cuvier, 75231 Paris cedex 05, France — Abstract. Pseudocetopsis orientale, a new catfish species of small body size of the cetopsid subfamily Cetopsinae is described from several Atlantic-slope rivers of Suriname and French Guiana. The combination of the presence of a dorsal fin with an ossified spinelet, the possession of pectoral- and dorsal-fin spines, the length of the pelvic and pectoral fins, the relative depth of the body, and the alignment of the dorsal and ventral profiles of the portion of the body posterior of the dorsal-fin base serve to distinguish the new species from all other cetopsines. — Resume. Pseudocetopsis orientale, une nouvelle espece de poisson chat Ce- topsinae de la famille des Cetopsidae, est decrit de plusieurs rivieres du Suri- name et de Guyane frangaise. La combinaison de plusieurs caracteres incluant la presence d'une nageoire dorsale avec un crochet ossifie, la presence d'epines dorsales et pectorales, la longueur des nageoires pelviennes et pectorales, la hauteur relative du corps et I'alignement des profits dorsaux et ventraux a I'arriere de la nageoire dorsale permet de distinguer cette espece de toutes les autres Cetopsinae. Recent studies have demonstrated that the Materials and Methods species-level diversity among catfishes of ^^j measurements were taken as straight the South American subfamily Cetopsmae as y^^^ distances between points with head & defined by de Pinna Vari (1995) is sig- j^j^g^h (HL) measured from the tip of the nificantly higher than the 12 species recog- ^nout to the end of the fleshy gill cover, nized by Burgess (1989), with five addition- interorbital width was taken as the shortest al species described by Ferraris & Brown distance between the orbits, but is, however, (1991), Lundberg & Rapp Py-Daniel (1994), difficult to measure unambiguously because Ferraris (1996), and Ohveira et al. (2001). of the fleshy tissues around the orbits. The Ongoing studies indicate that these 17 spe- soft bodies of most cetopsins make it dif- cies, nonetheless, represent a significant un- ficult to accurately measure most standard derestimate of the actual species-level diver- morphometric features. As a consequence sity within the subfamily, and we herein de- we do not provide these values for the spe- scribe a new species from Suriname and cies. Size of examined specimens is report- French Guiana discovered independently ed as standard length (SL) rounded to the during a revisionary study of the subfamily nearest whole millimeter. Median fin ray (RPV, CJF) and faunal studies of the ich- counts include all elements apparent in ra- thyofauna of French Guiana (PK). diographs. The number of vertebrae was VOLUME NUMBER 116, 3 693 MHNG mm Fig. 1. Pseudocetopsis orientale, holotype, 2621.040, 27 SL, Suriname, Brokopondo District, Mindrineti Kreek, close to mouth ofMaykaboeka Kreek, on the Gros Rosevel Mining concession (5°07'08.8"N, 55°16'59.4"W). taken from radiographs and includes the Pseudocetopsis cf. minutus Le Bail et al., four elements of the Weberian apparatus 2000:146, unnumbered figure [French and one element for the ural complex. Ver- Guiana, Fleuve Maroni, Fleuve Iracoubo, tebrae were separated into preanal, precau- Fleuve Comte, Fleuve Oyapock]. dal, and caudal elements with total verte- MUNG mm Holotype.— 2621-040, 27 brae the sum of precaudal and caudal ver- SL, Suriname, Brokopondo District, Min- tebrae. The presence of the sexually dimor- drineti Kreek, close to mouth of Mayka- phic features present in males of other boeka Kreek, Saramacca River basin, on cetopsin species was considered indicative Gros Rosevel Mining concession of the sex for those specimens that could (5°07'08.8"N, 55°16'59.4"W), R. Commerg- not be dissected but with these attributes. The range of values for meristic and mor- nat, J. Mol, a—nd C. Weber. Paratypes. All Suriname, Brokopondo phometric features in the species is pre- MHNG District, Saramacca River basin: sented first, followed by the values for the mm 2626.013, 9 ex., 18-27 SL (collected holotype in square brackets. Numbers of with holotype); USNM 369732, 2 ex., 21- specimens is indicated by "ex." Institution- mm al abbreviations are: AMNH, American 2M4NHN SL (collected withmmholotype); Museum of Natural History, New York; 2002.1625, 1 ex., 26 SL (col- NZCS ANSP, Academy of Natural Sciences, Phil- lected with hmolmotype); F7048, 1 specimen, 23 SL (collected with holo- adelphia; FMNH, Field Museum of Natural MHNG mm History, Chicago; MNHG, Museum type). MHNG2621.044, 2 ex., 22-22 mm d'Histoire Naturelle, Geneva; MNHN, Mu- SL and 2621.039, 4 ex., 21-26 SL, close to mouth of Maykaboeka Kreek, seum National d'Histoire Naturelle, Paris; on Gros Rosebel Mining concession (col- MZUSP, Museu de Zoologia da Universi- lected close to type locality), R. Commerg- dade de Sao Paulo; NZCS, National Zoo- MZUSP nat, J. Mol, and C. Weber. 65404, logical Collection of Suriname, Paramaribo; mm and USNM, National Museum of Natural 1 ex., 27 SL, Maykaboeka Kreek, Gros Rosebel Area, near Golden Star Concession History, Smithsonian Institution, Washing- (5°04'45"N, 55°16'09"W), C.A. Figueiredo, ton, D.C. E Breden, and H. Brook, Jan 2000. — Non-type specimens examined. 31 Pseudocetopsis orientale, new species mm specimens, 18-49 SL. Fig. 1 FRENCH GUIANA. MNHN 2002-1103, mm Hemicetopsis sp., Boujard et al., 1990:347 3 ex., 38-39 SL, no specific locality. MNHN mm [French Guiana, Fleuve Arataye]. Ponton 1994-0092, 1 ex., 30 SL, & Copp, 1997:241 [French Guiana, Fleuve Arataye, Saut Parare (4°03'N, MNHN Fleuve Sinnamary]. 52°42'W). 2002-1099, 2 ex., 38-39 694 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON — mm SL; Crique Boulanger of Fleuve Comte Description. Body moderately robust, MNHN (4°36'N, 52°19'W). 2002-1100, 1 somewhat compressed laterally anteriorly mm MNHN ex., 22 SL; 2002-1098, 2 ex., and becoming progressively distinctly com- mm 43-49 SL, Crique Balatee of Fleuve pressed posteriorly. Body depth at dorsal- MNHN Maroni (5°29'N, 54°03'W). 2002- fin origin approximately 0.21-0.23 of SL, mm 1 101, 8 ex., 24-44 SL, Degrad Florian and approximately equal to distance from of Fleuve Iracoubo (5°29'N, 53°33'W). anterior of eye to rear of head. Lateral line MNHN mm 2002-1 102, 1 1 ex., 40-49 SL, on body unbranched, midlateral, incom- Fleuve Oyapock. plete, and extending from vertical through SURINAME. All Nickerie District. pectoral-fin base posteriorly to point within FMNH mm 96268, 1 ex., 25 SL, Kaiser- region delimited anteriorly by vertical berg River (approximately 3°03'N, through middle of anal-fin base and poste- AMNH mm 56°35'W). 54828, 1 ex., 22 SL, riorly by vertical located proximate to an- stream near Avanavero, approximately 3 terior terminus of caudal peduncle. Dorsal miles (=4.8 km) downstream of DeVis profile of body nearly straight to slightly AMNH Falls (~4°48'N, 57°26'W). 55001, convex from nape to dorsal-fin origin and mm 1 ex., 32 SL, small stream on road straight from that point to caudal-fin base. from Lucie River Camp to Paramaribo, 25 Ventral profile of body slightly convex km N of Sisa Creek (~3°34'N, 57°37'W). along abdomen, approximately straight USNM mm 226146, 2 ex., 22-23 SL, along anal-fin base and converging towards woodland stream, 0.5 km from Camp Ma- dorsal profile of body posteriorly. Caudal- USNM taway (4°48'N, 57°43'W). 226147, peduncle depth greater than caudal-pedun- mm 7 ex., 18-24 SL (2 ex. cleared and cle length. stained), stream near Camp Anjoemara Head in profile acutely triangular overall USNM (4°50'N, 57°26'W). 226148, 1 ex., with bluntly pointed snout. Dorsal profile of 30 mm SL, stream at km 212 of road from head slightly convex from tip of snout to Amotopo to Camp Geology, at Machine vertical through posterior margin of orbit Park—Camp 212 (3°50'N, 57°34'W). and broadly convex from that point to nape. — Diagnosis. The combination of the Ventral profile of head slightly convex. presence of a dorsal fin with an ossified spi- Margin of snout in dorsal view broadly nelet and the presence of pectoral and dor- rounded. Postorbital margins of head slight- sal spines distinguishes Pseudocetopsis or- ly convex on each side from dorsal view. ientale from all other members of the Ce- Enlarged jaw musculature very evident on topsinae with the exception of P. minuta dorsal and lateral surfaces of postorbital (Eigenmann, 1912) from the Essequibo portion of head. River basin of Guyana. Pseudocetopsis or- Opercular membrane attached to isthmus ientate differs from P. minuta in the length only anterior of vertical through pectoral- of the pelvic fin (tip of fin reaches posteri- fin insertion. Opercular opening moderately orly to anterior margin of vent versus to elongate; opening extending anteroventral anal-fin origin, respectively), in the length of pectoral-fin insertion by distance approx- of the pectoral fin (tip of fin falls distinctly imately equal to one-third of head length short of vertical through pelvic-fin insertion and extending dorsal of pectoral-fin inser- versus reaches that line), the relative depth tion by distance equal to width of eye. of the body (0.21-0.23 of SL versus 0.17- Eye situated on lateral surface of head; 0.19, respectively), and in the alignment of located entirely dorsal to horizontal through the dorsal and ventral profiles of the portion pectoral-fin insertion; eye visible in dorsal of the body posterior of the dorsal fin (con- view, but not in ventral view, of head. Mid- verging slightly posteriorly versus parallel, dle of orbit at approximately 0.30 of HL. respectively). Eye diameter approximately one-third of VOLUME NUMBER 116, 3 695 snout length. Interorbital width approxi- rictus. Lateral mental-barbel origin situated mately equal to distance from tip of snout slightly posterior of vertical through medial to point within region between middle of mental-barbel origin. Tips of adpressed eye and posterior margin of orbit. Anterior mental barbels extend to, or barely beyond, narial opening circular, surrounded by opercular margin. short, anteriorly directed, tubular rim of Dorsal-fin rays 6 [6]. Dorsal fin moder- skin. Opening of anterior nares located ate, its base approximately 0.38-0.40 of slightly dorsal of horizontal that extends HL. Longest branched dorsal-fin ray, not through maxillary-barbel origin and at, or including distal filament present in mature slightly ventral of, horizontal through tip of males, equal in length to approximately snout. Distance between anterior nares ap- two-thirds of HL. Dorsal-fin spinelet pre- proximately equal to distance from tip of sent, first dorsal-fin ray spinous for basal snout to middle of orbit. Posterior narial one-half of length and flexible more distal- opening located on dorsal surface of head, ly, with distal filament present in mature situated dorsal to anterior one-third of orbit. males. Distal margin of dorsal fin slightly Narial opening nearly round and with flap convex, with first branched ray longest. of skin that nearly encircles opening, but Dorsal-fin origin located at approximately with small gap posteriorly; flap highest an- 0.29—0.33 of SL and along vertical that ex- terolaterally. tends through middle of adpressed pectoral Mouth subterminal, very wide; its width fin. Tip of adpressed dorsal fin, not includ- approximately 0.60 of HL. Margin of lower ing distal filament present in mature males, jaw gently rounded, its posterior limit reaching to vertical through anterior margin reaching to vertical through middle of orbit. of vent. Last dorsal-fin ray with slight basal Premaxillary tooth patch in form of gently posterior membranous attachment to body. arched band continuous across midline; an- Caudal-fin rays i,7,8,i [i,7,8,i]. Caudal fin terior margin convex, and posterior margin deeply forked, lobes symmetrical; tips of concave and parallel to anterior margin. lobes rounded. Length of longest caudal-fin Teeth on premaxilla small, conical, sharply ray approximately two times length of mid- pointed, and arranged in three regular rows dle rays. of uniform-sized teeth across entire pre- Anal-fin rays 23 to 27 [26], rarely 27. maxilla. Vomerine teeth in single arched Anal-fin base moderately long. Anal-fin or- row, with distinct gap in series at midline. igin located distinctly posterior of middle of Vomerine teeth conical, all of approximate- SL and anterior of middle of total length. ly uniform size, and with largest teeth in Anal-fin margin nearly straight in most ex- series approximately same size as largest amined specimens, but convex in presumed teeth on premaxilla. Dentary teeth compa- mature male as evidenced by presence of rable in shape to, but slightly larger than, filamentous dorsal- and pectoral-fin rays. premaxillary teeth. Dentary with three ir- Last anal-fin ray with slight membranous regular tooth rows medially that taper to attachment to body. one row laterally. Pelvic-fin rays i,5 [i,5]. Pelvic fin small; Maxillary barbel slender, its length ap- distal margin slightly convex with middle proximately equal to length of orbit plus rays longest. Pelvic-fin insertion located an- postorbital portion of head, and slightly terior to middle of SL and along vertical greater than three-quarters of HL; barbel or- through posterior limit of dorsal-fin base. igin located ventral to anterior margin of Tip of adpressed pelvic fin extending past orbit. Medial mental barbel slightly shorter middle of SL and reaching anterior margin than lateral mental barbel, with latter short- of vent. Last pelvic-fin ray with membra- er than maxillary barbel. Medial mental- nous attachment to body along basal one- barbel origin located along vertical through half of its length. 1 696 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Pectoral-fin rays 7 or 8 [7], rarely 8. Pec- fins of the specimen have an overlying sil- toral fin moderately long, its length slightly very sheen that is absent in preserved ma- more than 0.60 of HL. Pectoral-fin margin terial. — distinctly convex, with middle ray longest. Sexual dimorphism. The presumed ma- First pectoral-fin ray spinous with smooth ture males of P. orientale have filaments margins, spine short with length slightly present on the dorsal and pectoral fins and more than one-half that of first branched have the anal-fin margin slightly convex. ray; ray prolonged as filament in presumed Juveniles and females of the species, in mature male specimens. contrast, lack filaments on the fins and have Preanal vertebrae 12 to 15 [15]; precau- a straight anal-f—in margin. dal vertebrae 10 to 13 [11]; caudal verte- Distribution. Pseudocetopsis orientale brae 27 to 29 [28]; total vertebrae 39 to 42 is known from the Atlantic coastal rivers of [39], with 39 and 40 vertebrae most com- Suriname and French Guiana, in the region mon, and 42 vertebrae in only 1 of 54 ra- from the Corantijn River, that forms the diographed specimens (total includes radio- border between Suriname and Guyana, to graphed non-type specimens). Ribs 8 to 1 the Fleuve Oyapock-Rio Oiapoque along [10]. — the French Guiana-Brazil border. Given the Coloration in alcohol. Overall ground presence of this species in the Surinamese coloration of head and body pale and over- tributaries of the Corantijn River, it likely lain with rounded, large, brown chromato- also occurs in the left-bank tributaries to phores. Dark pigmentation on head and that river in Guyana. Similarly it is likely body tends to be more concentrated dorsal- that the species also occurs in the portions ly. Expanded chromatophores blend togeth- of the Rio Oi—apoque basin within Brazil. er to form uniform brown cast on some por- Etymology. The species name, orienta- tions of body in most specimens. Ventral le, from the Latin for eastern, refers to the surface of abdomen and head pale except distribution of this species in the eastern for scattered chromatophores on abdomen most portions of the known distribution of in some specimens and broad band of scat- the Cetopsinae. — tered, dark chromatophores that extend Ecology. The type locality is a rainfo- from symphysis of lower jaw to opercle. rest stream bordered by overhanging vege- Dorsal fin pale with some dark pigmen- tation that at the time of the collection had tation basally that forms somewhat diffuse low (40 cm deep), clear, slowly-moving wa- spot with margin of spot in form of semi- ter over a sand bottom with mud along the circle. Anal fin pale with scattered dark banks. The holotype and paratypes captured chromatophores basally. Pelvic and pectoral with it came from holes and fissures in de- fins pale. Caudal fin with few scattered dark caying branches submerged along the side MHNG, chromatophores that extend distally to at of the stream (C. Weber, pers. least middle of fin rays. comm.). Mol et al. (2000:430) characterize Maxillary barbel with scattered dark pig- the Maykaboeka Kreek as a low-gradient, mentation basally and pale distally. Mental second order drainage running through un- barbels pale. — disturbed rainforest. Non-type specimens Coloration in life. Le Bail et al. (2000: from Degrad Florian in the Fleuve Iracoubo (MNHN 147) provided a photograph of a live spec- basin, French Guiana 2002-1101), imen of the species (identified therein as were captured in a stream approximately 3 Pseudocetopsis cf. minutus), photographed m wide and 10-59 cm deep in clear, but in an aquarium immediately after capture. slightly tea-colored waters in areas with The overall dark pigmentation visible in the slow current densely shaded by the gallery photograph is comparable to that in the pre- forest. Observations at that locality indicate served specimens, but the head, body, and that during the day Pseudocetopsis orien- — VOLUME NUMBER 1 16, 3 697 tale is hidden in the sediment under leaves L. Lundberg and Mark Sabaj, ANSP; Mary or roots (PK). Anne Rogers, FMNH; Jean-Claude Hureau — Remarks. The question of generic hm- and Patrice Pruvost, MNHN; Claude Weber, MHNG; its within the Cetopsinae has been dis- Carlos A. Figueiredo and Mario cussed by various authors in recent years C.C. de Pinna, MZUSP; for access to or the including Ferraris & Brown (1991), Lund- loan of specimens that made this paper pos- berg & Rapp Py Daniel (1994), and Ferraris sible. Claude Weber also provided infor- (1996). Ongoing phylogenetic studies indi- mation on the type locality. Sandra J. Ra- cate that a revamping of some generic def- redon (USNM) provided technical support initions within the Cetopsinae may be nec- for the project and Pierre-Yves Le Bail, In- essary, but in the interim we assign the new stitut National de la Recherche Agrono- species to Pseudocetopsis in keeping with mique, provided critical assistance during the definition of that genus proposed by collecting efforts in French Guiana. Figure Ferraris & Brown (1991). 1 was prepared by T. Britt Griswold. This Pseudocetopsis minutus, which was orig- paper benefitted from comments and sug- inally described by Eigenmann (1912:211) gestions from Marcelo R. Britto, Ricardo as Hemicetopsis minutus from the Essequi- M.C. Castro, and Angela Zanata. bo River system, has been reported by sub- sequent authors from a series of localities Literature Cited distant from that drainage basin including French Guiana (see synonymy above), the Boujard, T, E J. Meunier, M. Pascal, & J. E Cosson. Rio Trombetas in the Amazon basin in Bra- 1990. Les Teleosteens—d'un haut bassin fluvial Guyanais, I'Arataye. 2 Inventaires des "non- zil (Ferreira, 1995:52), the Rio Caroni in Characoides." Cybium, 14(4):345-351. & Venezuela (Taphorn Garcia Tenia, 1991, Burgess, W. E. 1989. An atlas of freshwater and ma- A fig. 3; Lasso et al., 1990:1 17) and other riv- rine catfishes. preliminary survey of the Sil- ers in that country (Machado-Allison et al., uriformes. TEH. Publications, Neptune City, 1993:65, as Hemicetopsis minimus). Ongo- New Jersey, U.S.A., 784 pp. Eigenmann, C. H. 1912. The freshwater fishes ofBrit- ing studies indicate that P. minutus is rather ish Guiana, including a study of the ecological apparently endemic to the Essequibo River grouping ofspecies and the relation ofthe fauna — basin of Guyana and our comparisons here- of the plateau to that of the lowlands. Mem- in of P. orientale are limited to material of oirs of the Carnegie Museum, 5:xii + 578 pag- es, 103 plates. P. minutus from that river basin. — Ferraris, C. J., Jr 1996. Denticetopsis, a new genus of Comparative material examined. Pseu- South American whale catfish (Siluriformes: docetopsis minuta: British Guiana (=Guy- Cetop—sidae, Cetopsinae), with two new spe- ana) Amatuk (5°18'N, 59°18'W), FMNH cies. Proceedings of the California Academy 53262, 1 (18 mm SL, holotype of Hemi- of&ScBi.enAc.esBr4o9w(n6).:1196911-.17A0.new species ofPseu- cetopsis minutus). Siparuni VIII-2: Esse- , docetopsis from the Rio Negro drainage of Ve- — quibo River at Essequibo campsite nezuela (Siluriformes: Cetopsidae). Copeia ANSP (04°45'41"N, 58°45'53"W), 175839, 1991(1):161-165. mm 1 (21 SL). Ferreira, E. 1995. Composi9ao, distribui9ao e aspectos ecologicos da ictiofauna de um trecho do rio UHE Trombetas, na area de influencia da futura Acknowledgments Cachoeira Porteira, Estado do Para, Brasil. Acta Amazonica 23(1-4, Suplemento; issue for Research and museum visits associated 1993, published 1995):1-88. & with the preparation of this paper were Lasso, C. A., A. Machado-Allison, R. Perez Her- made possible by funding from the Neo- nandez. 1990. Consideraciones zoogeograficas de los peces de la Gran Sabana (Alto Caroni) tropical Lowlands Research Program of the We Venezu—ela, y sus relaciones con las cuencas ve- Smithsonian Institution. thank Scott A. cinas. Memoria Sociedad de Ciencias Natur- Schaefer and Barbara Brown, AMNH; John ales La Salle 50(133-134):109-129. 698 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Le Bail., P.-Y., P Keith, & P Planquette. 2000. Atlas Oliveira, J. C. de, R. P Vari, & C. J. Ferraris, Jr. 2001. des poissons d'eau douce de Guyane. Tome 2. A new species of "Whale catfish" (Silurifor- Fascicule II. Siluriformes. Museum National mes: Cetopsidae) from the western portions of — d'Histoire Naturelle, Service du Patronomie the Amazon basin. Proceedings ofthe Biolog- Naturel, Paris, and Institut d' Ecologie et de ical Society of Washington 1 14(3):574-578. Gestion de la Biodiversite, Paris. 307 pp. de Pinna, M. C. C, & R. P Vari. 1995. Monophyly & Lundberg, J. G., L. Rapp-Py-Daniel. 1994. Bathy- and phylogenetic diagnosis ofthe family Cetop- cetopsis oliveirai, gen. et sp. nov., a blind and sidae, with synonymization of the Helogenidae — depigmented catfish (Siluriformes: Cetopsidae) — (Teleostei: Siluriformes). Smithsonian Contri- from the Brazilian Amazon. Copeia 1994(2): butions to Zoology 51:1-26. 381-390. & & Ponton, D., G. H. Copp. 1997. Early dry-season Machado-Allison, A., C. Lasso, R. Royero-Leon. community structure and habitat use of young 1993. Inventario preliminar y aspectos ecolo- fish in tributaries of the River Sinnamary gicos de los peces de los Rios Aguaro y Guar- inqeuziuteola(.P—arMqeumeoNraicaionSaolc)i,edEasdtaddeo CGiueanrciicaos, NVae-- t(eFrreHnychdrGoudiaanma,oSpeoruatthioAnm.e—riEcnav)irboenfmoernetaanldBaif-- turales La Salle 53(139):55-80. ology of Fishes 50:235-256. Mol, J. H., D. Resida, J. C. Ramlal, & C. R. Becker. Taphorn, D. C, & J. G. Garcia Tenia. 1991. El Rio 2000. Effects of El Nino-related drought on Claro y sus peces, con consideraciones de los freshwater and bracki—sh-water fishes in Surina- impactos ambientales de las p—resas sobre la ic- me. South America. Environmental Biology tiofauna del bajo Rio Caroni. Biollania 8:23- of Fishes 59(4):429-440. 45.