UNIVERSITY OF AMSTERDAM. Callichthyidae) University of Amsterdam, Abstract. science: C. The remaining four species. described from elsewhere, viz.: C.

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1 Beaufortia INSTITUTE OF TAXONOMIC ZOOLOGY (ZOOLOGICAL MUSEUM) UNIVERSITY OF AMSTERDAM Vol. 33 no. 5 November 18, 1983 Review of genus Corydoras from Colombia, with descriptions of two new species (Pisces, Siluriformes, Callichthyidae) H. Nijssen & I.J.H. Isbrücker Institute of Taxonomic Zoology, University of Amsterdam, P.O. Box 20125, 1000 HC Amsterdam, The Nerlands Abstract This paper contains records and/or descriptions of twelve species of Callichthyid catfish genus Corydoras Lacepède, 1803, including two new species, from Colombian rivers, Rio Amazonas excluded: Corydoras trilineatus Cope, 1872, C. delphax n. sp., C. leucomelas Eigenmann & Allen, 1942, C. aeneus (Gill, 1858), C. melanotaenia Regan, 1912, C. metae Eigenmann, 1914, C. melini Lönnberg & Rendahl, 1930, C. reynoldsi Myers & Weitzman, 1960, C. axelrodi Rössel, 1962, C. loxozonus n. sp., C. elegans Steindachner, 1877, and C. simulatus Weitzman & Nijssen, The relationships of new species with or species of Corydoras are discussed. A key to species is provided. A Colombian representative of each species is illustrated. INTRODUCTION Two species are herein described as new to science: C. delphax and C. loxozonus. Twelve species of Callichthyid catfish genus The remaining four species were originally Corydoras Lacepede, 1803, are recorded in this described from elsewhere, viz.: C. aeneus (Gill, paper from Colombian rivers, Rio 1858) from Trinidad, C. trilineatus Cope, 1872, Amazonas excluded. Of this Colombian and C. leucomelas Eigenmann & Allen, 1942, material, morphometric and meristic data are from Peru (Corydoras caquetae Fowler, 1943, a given, according to methods described for junior synonym of C. leucomelas, was described species of genus Aspidoras Von Ihering, 1907 (cf. Nijssen & Isbriicker, 1976: 108). Of se twelve species, six have been originally from Colombia), and C. elegans Steindachner, 1877, from Brazil. Of all se species a Colombian specimen is originally described from Colombia: Corydoras illustrated. A key to species is provided. melanotaenia Regan, 1912, C. metae Eigenmann, Only those specimens which we have actually 1914, C. melini Lonnberg & Rendahl, 1930 examined have been included in this paper. (from Brazilian/Colombian border), C. Of twelve recorded species only one, Cory reynoldsi Myers & Weitzman, 1960, C. axelrodi doras melini, is found both in tributaries to Rfo Rossel, 1962, and C. simulatus Weitzman & Nijssen, Orinoco and in tributaries to Rio Amazonas (fig!) 53

2 Parintins) The occur in tributaries to following species Rio Orinoco (Rio Meta, Rio Guaviare, Rio Philadelphia, Penn. ( late Dr. J. E. Bohlke), British Museum (Natural History) (BMNH), Iniricla): C. delphax, C. aeneus, C. melanotaenia, C. London (Dr. P. H. Greenwood & Mr. G. J. metae, C. melini, C. axelrodi, C. loxozonus, and C. simulatus. In tributaries to Rio Amazonas (Rio Vaupes, Rio Caqueta) following species are found: C. trilineatus, C. leucomelas, C. melini, C. reynoldsi, and C. elegans. Howes), California of Academy Sciences San (CAS), Francisco, Cal. W. N. (Dr. Eschmeyer & Mrs. P. M. Museum of Sonoda), Comparative Zoology (MCZ), Cambridge, Mass. (Dr. W. L. Fink), Museum National d'histoire Naturelle (MNHN), Paris M. (Dr. It is reasonable to expect that several more L. Bauchot), Naturhistorisches Museum Wien species occur in Colombia, since ichthyofauna of this country is poorly known. Cala (1977: 12) listed seven species of Corydoras from Orinoco Basin of Colombia, without exact locality data or records of deposited specimens. Among se are Corydoras agassizii Steindachner, 1877, C. reticulatus FraserBrunner, 1938, and C. arcuatus Elwin, Although we rar expected se three species to occur in tributaries to Rio Amazonas, no specimens were available to justify confirmation of ir occurrence in Colombian waters. Although Corydoras melanotaenia was originally described from Rio Magdalena Basin (Honda), we were unable to find any Corydoras specimen from this river in museum col system (NMW), Vienna P. Kahsbauer & (Dr. Dr. R. Hacker), Senckenberg Museum (SMF), Frankfurt (Dr. W. Klausewitz), Naturhistoriska Riksmuseet (NRM), Stockholm S. (Mr. O. National Museum of Natural History (USNM), Washington D. C. (Dr. S. H. Kullander), Weitzman). Mr. M. L. Allender (USNM) made fig. 7, Mrs. M. P. Bakry (USNM) figs. 2, 5 and 14, Mr. D. Sminia (ZMA) fig. 11, Dr. S. H. Weitzman (USNM) figs. 8, 9 and 10, and Mr. 1. Mr. J. Zaagman (ZMA) fig. L. A. van der Laan (ZMA) made photographic illustrations figs. 3 and 12, and Dr. H. 6 Nijssen figs. and 13. This study has been made possible with lections. Subsequent to its original description, financial support of University of Amster C. melanotaenia was found only in upper Rio Meta. A sample with 17 specimens (SL dam (UvA), Nerlands Organization of Pure Research (ZWO), The Hague, and of Smithsonian Institution, Washington D. C. mm) of Corydoras hastatus Eigenmann & Eigenmann, 1888 (typelocality: Brazil, Amazonas, IUM = Indiana University Museum (ma Villa Bella = was examined in SU terial partly in CAS) = Stanford University (material now in Frankfurt (SMF 4970). They are said to be collected by Baumert in 1955 in Colombia, Bolivar, Rio Carnavales near Espiritu. We are CAS) ZMA Zoologisch Museum, Amsterdam = unable to trace this river, and do not trust this record. KEY TO THE SPECIES OF CORYDORAS FROM From Departamento de Bolivar, Colombia, no specimens of Corydoras are known to us. COLOMBIA la Pectoral fin spine with a stronly serrated medial border 11 lb Pectoral fin spine without a strongly serrated medial border 2 ACKNOWLEDGEMENTS For loan and/or exchange of specimens, and for information received, wish we to express our gratitude to following museums and colleagues: Academy of Natural Sciences (ANSP), 2a Dorsolateral body scutes with a prominent oblique dark stripe 8 2b Dorsolateral body scutes without a prominent oblique 3 stripe Body with distinct markings 4 3a 3b Body with even brownish to greyish pigment, not forming distinct markings 5 54

3 Corydoras CAS/SU The Holotype, NRM Ground 4a 4b A large dark blotch on anteriodorsal of dorsal part fin; body with a dark midlateral zigzag stripe, above and below margined with white rcorydoras trilineatus Cope, 1872 Anterior margin of dorsal fin entirely or partly dark; body without midlateral stripe 6 (one), SL 40.2 mm, Caqueta near Tres Esquinas (00 43'N, 75 14'W), tributary to Rio Caqueta, coll. M. Rakowicz, ; CAS/SU (one), SL 33.9 mm, Caqueta, Tres Esquinas, coll. T. D. White et al., 5a Body depth in SL; snout length in b HL; interorbital width in HL; 910 branched pectoral fin rays... melanotaenia Regan, 1912 Body depth 2.6 in SL; snout length 2.1 in HL; interorbital width in HL; 8 branched pectoral fin rays Corydoras aeneus (Gill, 1858) two Colombian specimens examined hardly differ from lectotype and paralectotype from Peru (ANSP 8294 and 8295, SL 33.7 and 34.7 mm, respectively). The length 6a Body with two prominent dark blotches about of snout, expressed as a ratio of HL is midlateral line, one below dorsal fin, one below adipose fin (Corydoras reynoldsi Myers & Weitzman, b Body with numerous small, dark 7 spots in Colombian specimens, against in two typespecimens. Corydoras trilineatus can be easily identified by 7a A dark vertical line on posterior margin of scutelets its distinctive colour pattern (fig. 2). The inner on caudal fin base, followed by a narrow, white band margin of pectoral fin spine is weakly ser reaching to vertical bar oncaudal fin rays rated. The intercoracoid area is covered with 7b (Corydoras leucomelas & Eigenmann Allen, 1942 No dark vertical line on scutelets on caudal fin base, mosaiclike dermal ossifications. no white band oncaudal fin rays (Corydoras delphax n. sp. 8a Dorsal fin with a large dark blotch 9 8b Dorsal fin without a large dark blotch 10 Corydoras delphax n. sp. (figs. 1, 3, 4a; table I B) 9a Dorsolateral body scutes with dark pigment on middorsum beyond dorsal fin Materialexamined b (Corydoras metae Eigenmann, 1914 Dorsolateral body scutes with an unpigmented zone (holotype), SL 49.7 mm; NRM (five paratypes), ZMA (two onmiddorsum dorsal fin beyond <Corydoras melini Lonnberg Rendahl &, a Body scutes with five longitudinal series of spots below dorsolateral body stripe (Corydoras loxozonus n. sp. paratypes), SL mm, Guainia, Rio Imrida system, Cano Bacon, Pueblo Bretania (03 43'N, 67 59'W), coll. T. Hongslo, 30V b Body scutes without longitudinal series of spots below Description. SL 49.7 mm; body 11a dorsolateral body stripe (Corydoras axelrodi Rossel, 1962 Snout acute, elongate; ventral margins of coracoid not meeting along abdominal midline (Corydoras simulatus Weitzman & Nijssen, 1970 depth 20.6 mm; body width 13.1 mm; length dorsal spine 13.1 mm; length pectoral spine 13.6 mm; head length 17.3 mm; snout length 9.2 mm; length bony orbit 4.5 mm; interorbital lib Snout round, short; ventral margins of coracoid width 7.7 mm; width intercoracoid area 6.7 meeting along abdominal midline ( Corydoras elegans Steindachner, 1877 mm; depth caudal peduncle 7.2 mm; fontanel length 6.8 mm. Pectoral fin with 8 branched rays. Dorsolateral body scutes 24, ventrolateral SYSTEMATIC ACCOUNT body scutes 22, preadipose scutes 2. Two pairs of rictal barbels, one pair of mental barbels. Corydoras trilineatus Cope, 1872 (figs. 1,2; table I A) Corydoras trilineatus Cope, 1872: 281, pi. VI fig. 2 (original description; typelocality: Peru, "Rio Ambiacu" Rio = Ampiyacu; 2 syntypes; lectotype Medial border of pectoral fin spine weakly serrated (fig. 4a). Intercoracoid area naked. Morphometric data, expressed SL or of HL of holotype paratypes are presented in table I B. as a ratio of and of designated by Nijssen & Isbriicker, 1980: 194). Colour in alcohol (fig. 3). colour tan, dorsolateral body scutes darker slightly Material examined than ventrolateral scutes. Dark pigment on 55

4 Fig. 1. Map of eastern Colombia, showing three tributaries to Río Orinoco with eight species of Corydoras, and two tributaries to Río Amazonas with five species. 56

5 The Fig. 2. Corydoras trilineatus Cope, 1872, Río Orteguaza, CAS/SU 52596, SL 40.2 mm. dorsum of head across eyes, posteriorly from interorbital area towards base of supraoccipital. Body with a dark, squarish blotch on dorsolateral body scutes, below numerous than on dorsal fin. Adipose fin membrane tan. Pectoral, and pelvic, anal fins without pigment. Variability in The paratypes. pigmentation on body scutes, including extension of blotch below dorsal fin, differs in size and distribution. It forms eir narrow lines confined to margins of scutes, or irregular, small on spots scutes. Almost each specimen shows variation The (fig. 3). spots on caudal fin are sometimes conspicuous, arranged into irregular vertical series, or are less prominent, like in holotype. Etymology. specific name delphax is Greek, meaning young pig, an allusion to its base of dorsal fin spine and three ad feeding behaviour. jacent branched rays, including fin membrane, extending on fin through distal Comparison. Corydoras delphax is reminiscent of C. ambiacus Cope, 1872, originally tips of spine and rays. Margins of dorsoand described from Peru, with which it shares all ventrolateral body scutes with dark pigment, forming thin irregular lines. of Lighter part dorsal fin and entire caudal fin with minute and morphometric meristic characters. We examined holotype of C. ambiacus (ANSP 8291, SL 43.7 mm) and numerous additional dark spots, those on caudal fin more specimens. The dark blotch on dorsal fin, which in C. delphax continues to distal tips of spine and rays, is confined in C. ambiacus to lower anterior half. The ground colour of delphax is tan, whitish in C. ambiacus. The markings on body and fins in C. ambiacus are welldefined and more conspicuous than in C. delphax. Corydoras delphax has a colour pattern reminiscent of both C. ambiacus and C. leucomelas. Corydoras delphax is compared specimens of C. leucomelas. ~ C. with Colombian It reaches a SL of 57

6 n. sp.; above: SL 49.7 holotype, mm; below: a paratype, ZMA , SL 47.2 mm, showing variability of colour Fig. 3. Corydoras delphax pattern mm, against 40.9 mm in C. leucomelas. The in C. delphax, against in C. body width in SL is in C. delphax, leucomelas. The pectoral fin spine length in SL is against in C. leucomelas (SL in C. delphax, against in C. mm). The dorsal fin spine length in SL is leucomelas. The snout length in HL is in 58

7 The c) e) ANSP Fig. 4. Profiles of pectoral fin spines of: a) Corydoras delphax n. sp., left spine of a paratype, SL 47.2 mm; b) Corydoras melanotaenia Regan, 1912, right spine of lectotype; Corydoras metae Eigenmann, 1914, left spine of holotype; d) Corydoras melinilönnberg & Rendahl, 1930, left spine of lectotype; left spine of holotype. Corydoras axelrodi Rössel, 1962, C. delphax, against length of bony in C. leucomelas. The orbit in HL is in C. ported in Nerlands some years ago as aquarium fishes, which can be identified as C. delphax, against in C. leucomelas. delphax in same way as illustrations in The colour pattern of C. leucomelas closely resembles that of C. ambiacus in intensity of Burgess (1982 a & b). dark markings. However, pigmentation on dorsal fin is similar to that in C. delphax. Characteristic for C. leucomelas is a dark vertical line on posterior margin of scutelets on Corydoras leucomelas Eigenmann & Allen, 1942 (figs. 1, 5; table I C) caudal fin base, followed by a narrow, unpigmented band. Corydoras sp. illustrated in Burgess (1982 a: 73, unidentified specimen figured in middle of third out of five rows of photographs; also in Burgess, 1982 b: 12, as Corydoras melanistius? [non Regan, 1912], Corydoras leucomelas Eigenmann & Allen, 1942: 178, pi. XII fig. 4 (original description; typelocality: "Yarinacocha" = Peru, Yarinacocha, cutofflake at bank of right Rio Pacaya, tributary on left bank of Rio Ucayali near Sarayacu (about 05 15'S, 74 15'W); holotype only). Corydoras caquetae Fowler, 1943: , figs (original description; typelocality: "Florencia, Rio Orteguasa, Colombia"; holotype only). four photographs, one in right hand of second row from above, and three of third row) Material examined may well represent Corydoras In delphax. addition, we have seen still living specimens im (holotype of Corydoras caquetae Fowler, 1943), SL approximately 28.3 mm, Rio Caqueta, 59

8 C) The ,8 See / CAS CAS/SU CAS/IUM Table I: Morphometric and meristic data of: A) Corydoras trilineatus Cope, 1872; B) Corydoras delphax n. sp., holotype and paratypes; Corydoras leucomelas Eigenmann & Allen, 1942; specimen in second column is holotype of C. caquetaefowler, 1943; D) Corydoras aeneus (Gill, 1858); Río Magdalena are lecto and paralectotype. E) Corydoras melanotaenia Regan, 1912; specimens from species A B C C D D E E N river system Caqueta Im'rida Caqueta Caqueta Guaviare Meta "Magdalena" Meta SL in mm SL/body depth SL/body width SLlength dorsal spine SL/length pectoral spine SL/head length HL/snout length HL/length bony orbit HL/width interorbital HL/depth caudal peduncle P 2 1,8 1,8 1,78 1,910 DBS/VBS 23/21 24/ / /21 24/21 PAS " 2425/ Orteguaza at Florencia (01 37'N, 75 37'W), Material examined coll. Niceforo Maria, 1932;USNM SL 20.0 (one), mm, same data as holotype of Corydoras CAS/SU caquetae; (five), SL SL (one), 35.6 mm, Meta, Rio Guaviare Cordillera system Macarena, small brook into Rfo Guayabero (02 17'N, 73 44'W) 5 miles mm, Caqueta, Rio Orteguaza near below El Refugio, alt. 300 m, coll. T. White & Tres Esquinas (00 43'N, 75 14'W), tributary G. S. Myers, ; to Rio Caqueta, coll. M. Rakowicz, (one), SL 41.2 mm, Meta, upper Rio Meta, Colombian specimens were Quebrada Cramelote, Villavicencio, coll. M. compared with holotype (CAS/IUM 15818, Gonzales, ; (two), SL 26.7 mm) from Peru. The head length in SL SL mm, Meta, Rfo Negro at is in five specimens 52598, against 2.9 in holotype. in CAS/SU The interor Villavicencio (04 09'N, 73 38'W), coll. M. Gonzales, bital width in HL is in Colombian under Corydoras melanotaenia specimens, against 2.2 in holotype. The inner margin of pectoral fin spine is finely serrated. In larger specimens, intercoracoid area is covered with small, mosaiclike dermal ossifications. Corydoras aeneus (Gill, 1858) (figs. 1, 6; table I D) below. Corydoras melanotaenia 1912 Regan, (figs. 1, 4b, 7; table I E) Corydoras melanotaenia Regan, 1912: (original description; typelocality: Colombia, "Honda" (12 21'N, 71 47'W), Rio Magdalena basin; 2 syntypes; lectotype designated by Nijssen & Isbriicker, 1980: 208). Hoplosoma aeneum Gill, 1858: 403 (original description; typelocality: "...clear streams of island of Trinidad..."; 4 syntypes; lectotype designated by Nijssen & Isbriicker, 1980: 208). Material examined. BMNH :41 SL 40.9 (lectotype), mm, locality coll. B. BMNH questionable, Leighton; 60

9 Fig. 5. Corydoras Fig. 6. Corydoras leucomelas aeneus Eigenmann (Gill, 1858), & Allen, small brook 1942, into Río Río Orteguaza, CAS/SU 52598, SL 33.9 Guayabero, CAS/SU 53763, SL 35.6 mm. mm. 61

10 USNM CAS/IUM CAS/IUM CAS CAS/SU ZMA USNM ZMA RMNH :42 (one paralectotype), SL 31.2 mm, 1914; (two), SL of largest same data as lectotype; , 39.4 mm, Meta, along road Villavicencio to ZMA (eight), SL mm, Meta, upper Rio Meta, S.E. of Villavicencio, coll. R. Socolof, XII1963; Puerto Lopez, coll. A. Werners, Corydoras melanotaenia resembles C. aeneus in pigmentation. The body depth in (fourteen), SL mm, Meta, Rio SL is in C. melanotaenia (24 specimens, Manacacias, surroundings of Restrepo, coll. R. including lecto and paralectotype), against Socolof, 14XII1963; in C. aeneus from Colombia. The snout (seven), ZMA (two), USNM (three), SL mm, Meta, Rio Ocoa length in HL is in C. melanotaenia, near Puerto Lopez, coll. K. Nelson, against 2.1 in Colombian C. aeneus. The interorbital width in HL is in C. 23VIII1961; CAS/SU (four), Rio melanotaenia, against in C. aeneus. Corydoras Ocoa; (three), SL melanotaenia has 910 branched pectoral fin rays, mm, Meta, Cario Pachaquiaro near Puerto against 8 in C. aeneus. Unfortunately, only four Lopez, coll. K. Nelson, 22VIII1961; USNM (one), SL 25.7 mm, Meta, Rio specimens of C. aeneus were available from Colombia, two of which could be measured and Quenane near Puerto Lopez, coll. K. Nelson, counted. 22VIII1961; (one), SL Corydoras melanotaenia appears to be confined 30.5 mm, Meta, Rio Meta at Barrigona (Puerto Barrigon, 04 10'N, 'W), coll. M. to Colombia, whereas C. aeneus is a widespread species. Gonzales, 1914; (four), SL Eigenmann (1922: 65, 220, 228) expressed mm, Meta, Rio Negro at Villavicen his doubt about typelocality of C. melano cio (04 09'N, 73 38'W) coll. M. Gonzales, taenia as originally recorded by Regan. In his 1914; (one), SL 34.5 mm, opinion, C. melanotaenia was shipped from Hon Meta, tributary to Rio Meta near Cumaral, da, although it was probably collected in coll. A. Maria, 1917; (one), Rio Meta Basin. Miles (1945) did not record SL 37.7 mm, Guaicaramo, coll. M. Gonzales, any Corydoras species from Rio Magdalena. Fig. 7. Corydoras melanotaenia Regan, 1912, Caño Pachaquiaro, USNM , SL 46.6 mm. 62

11 ZMA USNM CAS/IUM USNM ANSP See RMNH SMF NRM ANSP NRM Dahl (1971: vii) confirmed opinion of Meta, Rio Manacacias near Restrepo, coll. R. Eigenmann. So far, we did not obtain any Cory Socolof, 14XII1963; (five), doras specimen from Rio Magdalena Basin, Meta, Cano Angosturas near Hacienda which supports Eigenmann's opinion. Humacita, coll. J. E. Bohlke, N. & D. Foster, ; (three), Meta, Corydoras metae Eigenmann, 1914 Cano Angosturas near Hacienda Humacita, (figs. 1, 4c, 8; table II F) Corydoras metae Eigenmann, 1914: 230 (original description; typelocality: "Barrigona, Rio Meta, Colombia"; holotype), Eigenmann, 1916: 78, pi. XIV fig. 1 (listed; illustration of holotype), Eigenmann, 1922: 227, pi. VIII fig. 5 (listed; illustration of holotype). Material examined coll. J. E. Bohlke, N. Foster & J. Thomerson, ; (one), SL 37.8 mm, Meta, road along Villavicencio to Puerto Lopez, coll. A. Werners, 1972; USNM (ten), SL mm, Meta, Cano on Negro road to Puerto Porfio, E. of Villavicencio, coll. E. Thomerson et J. al., ; 8181 (nine), SL (holotype), SL 38.0 mm, Rio Meta, Barrigon, mm, Meta, Rio Meta near Villabo, coll. C. A. coll. M. Gonzales, 1914; Velasques, 3/511962; (two), SL mm, Meta, (three), SL mm, Meta, Cano Negros Cano Pachaquiaro at Puerto Lopez, coll. K. Nelson, (04 05'N, 73 33'W), coll. T. Hongslo, 22VIII1961; (two), SL 24VII1971; (one), SL mm, Meta, Rio Ocoa at Puerto Lopez, coll. K. Nelson, 23VIII1961; ANSP (one), SL 37.4 mm, Meta, Rio 29.8 mm, Meta, Peralonzo Cano Pachaquiarito (04 06'N, 73 10'W), coll. T. Hongslo, Meta at Villavicencio, coll. C. Miles, X1940; under Corydoras melini Lonn (four), SL mm, berg & Rendahl, 1930, below. Fig. 8. Corydoras metae Eigenmann, 1914, exact locality unknown, CAS/SU 52587, SL 27.0 mm. 63

12 G) NRM/SMNH 42.3 Corydoras melini Lönnberg & Rendahl, 1930 Florencia (01 35'N, 75 36'W), coll. G. S. (figs. 1, 4d, 9; table II G) Myers et al., Corydoras melini Lonnberg Rendahl, 1930: 16, figured & (original description; typelocality: "Jauarete an dem Ausfluss des Rio Papuri in den Rio Uaupes (Rio Waupes deutscher Atlanten), 68, 5 w.l., 113 n.b 5 syntypes; lectotype designated by Nijssen & Isbrucker, Corydoras melini is reminiscent of C. metae in and meristic morphometric characters, and in details of ir colour pattern. However, C. melini has a whitish ground colour, whereas in C. metae ground colour is 1980: 209). tan, often with a pink hue. Corydoras melini has an unpigmented area dorsal to oblique Typelocality: Brazil/Colombia, Iuarete at stripe on body, posterior to base of confluence of Rio Papuri and Rio Uaupes last dorsal fin ray (fig. 9). In C. metae dark (00 35'N, 69 13'W). Material examined (lectotype), SL 44.4 mm, NRM/SMNH body stripe meets on middorsum beyond dorsal fin (fig. 8). In 13 specimens of C. melini (SL (four paralectotypes), SL 31.4 mm, mm, including lectotype and paralec locality data as above, coll. D. Melini, 1924; CAS/SU 53738, CAS/SU (fortytwo), SL max mm, Meta, Cordillera Macarena, Rio Losada (02 12'N, 74 04'W), coll. T. D. White & G. S. Myers, ; CAS/SU (fourteen), SL mm, totypes), body depth in SL is , against in 16 specimens of C. metae (SL mm, including holotype), whereas body width of C. melini is in SL, against in C. metae. Corydoras melini has 2325/2123 dorso/ and ventrolateral body Caqueta, Rio Orteguaza at Puerto Lara near scutes, against 2023/1920 in C. metae. Table II: Morphometric and meristic data of: F) Corydoras metae Eigenmann, 1914; specimen in first column is holotype; paralectotypes; Corydoras melini Lönnberg & Rendahl, 1930; specimens from Río Vaupés are lectotype and H) Corydoras reynoldsi Myers & Weitzman, 1960, holotype and paratypes. species F F F G G H N river system Meta Meta Guaviare Vaupes Caqueta Caqueta SL in mm SL/body depth SL/body width SL/length dorsal spine SL/length pectoral spine SL/head length HL/snout length HL/length bony orbit HL/width interorbital HL/depth caudal peduncle P 2 1,8 1,78 1,8 1,89 DBS/VBS 22/ / / / ,8 2324/2021 PAS " 24 64

13 Fig. 9. Corydoras melini Lönnberg & Rendahl, 1930; above: Río Losada, CAS/SU 53738, SL 23.0 mm; below: upper Río Orteguaza, CAS/SU 53686, SL 32.5 mm, showing variability of colour pattern. 65

14 CAS/SU USNM See USNM SMF Corydoras reynoldsi Myers & Weitzman, 1960 (figs. 1, 10; table II H) Corydoras axelrodi Rössel, 1962 (figs, 1, 4e, 11; table III J) Corydoras reynoldsi Myers & Weitzman, 1960: , figs. Corydoras axelrodi Rossel, 1962: , figs. 13 (original 23, table 2 (original description; typelocality: "...Tres Esquinas Station no. 12,...A small stream tributary to description; typelocality: "Columbien, Rio Meta"; holotype and two paratypes). Rio Orteguaza opposite town and air base known as Tres Esquinas, CaquetaProvince, Colombia....approximately at 0 45'N., 75 15'W.; holotype and 7 paratypes). Material examined SL (holotype), 35.9 mm, SMF 5701/5702 (two paratypes), SL mm, Rio Meta, coll. Material examined K. Swegles; (ninety), ZMA (holotype), SL 27.3 mm, CAS/SU (six (five), SL mm, Meta, mouth paratypes), ZMA (one paratype), SL of cano into Rio Manacacias at Puerto Gaitan mm, Caqueta, small tributary to Rio (06 15'N, 71 27'W), coll. J. E. Thomerson et Orteguaza opposite Tres Esquinas, coll. G. S. al., 2IV1974; (one), SL Myers, T. D. White, J. N. Reynolds & L mm, Meta, Restrepo, don. H. R. Axelrod Wulff, through R. Socolof, V1963. Corydoras reynoldsi has a comparison with Corydoras characteristic colour pattern (fig. 10). loxozonus n. sp.. Fig. 10. Corydoras reynoldsi Myers & Weitzman, 1960, holotype (reproduction of illustration in Myers & Weitzman, 1960, fig. 2). 66

15 ANSP Ground Fig. 11. Corydoras axelrodi Rössel, 1962, holotype. Corydoras loxozonus n. sp. (figs. 1, 12; table III K) eyes on ossified of parts head, suggesting a mask. Illdefined dark brown pigment between posterior part of head, anterior to Material examined base of dorsal fin spine. (holotype), SL 35.7 mm, Meta, Lomalinda near Rio Ariari, tributary to Rio Guaviare, S.E. of Villavicencio, col. E. J. Hugghins, 20VIII1969. Description. Holotype, SL 35.7 mm; body depth 14.4 mm; body width 9.8 mm; length dorsal spine 9.7 mm; length pectoral spine 11.0 mm; head length 11.6 mm; snout length 5.9 Dorsal fin base and dorsal margin of body scutes, between last dorsal fin ray and base of adipose fin spine, with dark pigment forming a narrow line. This line continues on dorsal margin of scutes between adopose fin membrane and base of caudal fin. A conspicuous dark brown oblique stripe runs from below base of dorsal fin spine mm; length bony orbit 4.2 mm; interorbital to small scutelets on caudal fin base, width 5.1 mm; width intercoracoid area 4.1 posterior to last ventrolateral body scute. mm; depth caudal peduncle 5.6 mm; fontanel This stripe is margined dorsally and ventrally length 4.1 mm. Pectoral fin with 7 branched by an unpigmented zone, dorsal one tan, rays. Dorsolateral body scutes 24, ventrolateral ventral zone whitish. body scutes 20, preadipose scutes 4. Two pairs The body of rictal barbels, one of pair mental barbels. Medial border of pectoral fin spine weakly serrated. Intercoracoid area with minute scattered ossifications. Morphometric data, expressed as ratios of SL scutes below ventral unpigmented zone show five series of longitudinal for spots. Except a series of minute spots on midline, se spots become gradually smaller ventrally. Dorsal fin with a dark brown line between or of HL are given in table III K. spine and anterior margin of second branched Colour in alcohol (fig. 12). colour ray, membrane included, extending to distal tip tan. Dark brown pigment on dorsum of head of first and second ray, not reaching base of across eyes, posteriorly reaching supraoccipital process, extending base of below se rays. 67

16 Fig. 12. loxozonus Corydoras fin Remaining dorsal in spots halfway ir distal spine a about one or rays, vertical some of tips near pigment, upper of spots series lines, brown dark brown small, About three fin anterior oblique spot. with faint tion form ir one more pigmentation and near halfway all on Pectoral some and scattered, The colour fins pelvic hyaline, for minute dots. in may have although faded during its period of preservation. Etymology. coined from and Latin to The dark loxos name loxozonus is meaning slanting meaning belt, girdle, oblique stripe on in allu body. pigmentabody, proportions of C. specimen ozonus greatly until all deckeri, that are a were now to single pectoral fin axelrodi. of Corydoras ANSP in specimen with that of C. nomen loxozonus a data specimen certain occurs that C. in & living pattern (Riehl of by specimens (Riehl new 1982a: 74, None nudum). accompanied lox We as colour a ; Burgess, locality ir seven holotype specimens 1982: The JK). received colour slides of we similar accurate C. describe to Baensch, slides in The borrowed from was species III (table loxozonus has against eight as loxozonus. specific with C. axelrodi. 68 across Corydoras loxozonus and C. axelrodi share body C. specific Greek zona C. mask a sides of on dark conspicuous a body and Corydoras axelrodi lacks aquarium holotype is wellpreseverd, pattern except sharing fins and hesitated rays. on is reminis Corydoras loxozonus axelrodi, stripe present rays base of three anterior rays, sion of C. cent lobe in than ors. conspicuous Anal series, Comparison. eyes. with Caudal fin with distal regular minute dark tip. membrane with complete. with rays length of fin Adipose holotype. sp., horizontal two n. Colombia). is se and/or Baensch loxozonus & as not state We con

17 CAS/SU USNM USNM NRM SMF Table III: Morphometric and meristic data of: J) Corydoras axelrodi Rössel, 1962; specimens in first column are holotype and paratypes; K) Corydoras loxozonus n. sp., holotype; L) Corydoras eleganssteindachner, 1877; M) Corydoras simulatus Weitzman & Nijssen, 1970; specimens in first column are holotype and paratypes. species J J K L M M N river system Meta Meta Guaviare Caqueta Meta Meta SL in mm SL/body depth SL/body width SL/length dorsal spine SL/length pectoral spine SL/head length HL/snout length HL/length bony orbit HL/width interorbital HL/depth caudal peduncle P 2 1,8 1,8 1,7 1,8 1,9 1,9 DBS/VBS 2324/ /20 24/20 24/21 24/ /2122 PAS Corydoras elegans Steindachner, 1877 (figs. 1, 13; table 111 L) Corydoras elegans Steindachner, 1877: (original description; "Cudajas,... syntypelocalities in Brazil: are Teffe"; lectotype designatedby Nijssen & Isbriicker, 1980: 213, from Brazil Amazonas, Rio Corydoras simulatus Weitzman & Nijssen, 1970 (figs. 1, 14; table III M) Corydoras simulatus Weitzman & Nijssen, 1970: , figs. 4, 6d (original description). Amazonas at Tefe; 359 paralectotypes). Material examined Material examined (holotype), SL 51.0 mm, USNM (four (one), SL 40.0 mm, Caqueta, near Tres Esquinas (00 43'N, to Rio 75 14'W), tributary Caqueta, coll. M. Rakowicz, paratypes), ZMA (two paratypes), SL mm, Meta, Rio Ocoa near Puerto Lopez (04 06'N, 72 57'W), Rio Meta system, Corydoras elegans has a wide area coll. K. Nelson, 23VIII1961; USNM of distribution. Its colour pattern is variable, (one paratype), SL 52.9 mm, Meta, different in both sexes. Cano Pochaquiaro at Via Puerto Lopez, coll. C. elegans is easily recognizable by its short, K. Nelson, 22VIII1961; round snout, by its coracoid margins which are 3878 (three), ZMA (two), SL close to each or ventrally, and by its strongly serrated medial edge of pectoral fin spine. mm, Meta, Quebrada Venturosa (about 04 04'N, 72 59'W), coll. T. Hongslo, The Colombian specimen differs slightly 24VII1971; (one), SL 29.6 from lectotype (NMW 46729, SL 42.8 mm) and mm, Meta, 20 paralectotypes (NMW (4), MCZ 8203 Cano into Rio Manacacias at Puerto Gaitan (06 15'N, 71 27'W), coll. J. E. (12), MNHN 89276/279 (4), SL Thomerson et al., 2IV1974; 8803 mm) from Brazil, by having a slightly shorter dorsal fin spine (4.8 in SL against ), and (one), SL 41.7 mm, Meta, Cano Pochaquiarito near Villabo, coll. C. A. Velasques, by having 24 dorsolateral body scutes against 2223 in typespecimens. 69

18 Fig. 13. Corydoras eleganssteindachner, 1877, tributary Fig. 14. Corydoras 1970, 70 fig. 4). simulatus Weitzman & Nijssen, to 1970, Río Caquetá, CAS/SU holotype (reproduction 52597, SL of illustration 40.0 mm. in Weitzman & Nijssen,

19 , The, colour pattern of Corydoras appendix upon fishes of Rio Meta in simulatus reminds of that of C. metae and C. melini C. simulatus can easily be distinguished several and meristic by morphometric characters (tables II FG and III M), and especially by its strongly serrated medial edge of pectoral fin spine. Colombia. Mem. Carnegie Mus., 9(1): 1346, pis. I XXXVIII. MILES, C., Los del Rio peces Magdalena ("A field book of Magdalena fishes"),: 1214, (xiii), xivxxviii (Ministerio de la Economia Nacional, Seccion de Piscicultura, Pesca Caza, y Bogota). MYERS, G. S. & S. H. WEITZMAN, Two fishes new collected by General Thomas D. White in eastern Colombia. Stanford ichth. Bull., 7 (4): REFERENCES NIJSSEN, H. & I. J. H. ISBRUCKER, The South American plated catfish genus Aspidoras R. von BURGESS, W. E., 1982a. Corydoras & Co., part Fish Hobby., 30 (12): Trop. Ihering, 1907, with descriptions of nine new species from Brazil (Pisces, Siluriformes, Callichthyidae). 1982b, Corydoras & Co., part 3. Trop. Fish Bijdr. Dierk., 46 (1): Hobby. 31 (2): 814. CALA, P., Los peces de la Orinoquia colombiana: A review of genus Corydoras Lacepede, 1803 (Pisces, Siluriformes, Callichthyidae). Bijdr. lista preliminar anotada. Lozania, 24: 121. DAHL, G., Los del norte de peces Colombia,: I XVII, 1391 (i) (Ministerio de Agricultura, INDER ENA, Bogota). Dierk., 50 (1): RIEHL, R. & H. A. BAENSCH, AquarienAdas,: 1992 (Mergus Verlag fur Natur und Heimtierkunde, Baensch, Melle). EIGENMANN, C. H., New and rare fishes from South WEITZMAN, S. H. & H. NIJSSEN, Four new species American rivers. Ann. Carnegie Mus., 10 (12): 77 86, pis. XIIIXVI. and one new subspecies of catfish genus Corydoras from Ecuador, Colombia and Brazil (Pisces,, The fishes of western South America, part I. Siluriformes, Callichthyidae). Beaufortia, 18 (233): The freshwater fishes of northwestern South America, including Colombia, Panama, and Pacific slopes of Ecuador and Peru, toger with an Received: January 27, 1983 Institute of Taxonomic Zoology (Zoological Museum), University of Amsterdam, P.O. Box 20125, 1000 HC The Amsterdam, Nerlands 71