aqua, International Journal of Ichthyology

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1 aqua, International Journal of Ichthyology Description of a new species of catfish from the upper rio Paraíba do Sul basin, south-eastern Brazil (Teleostei: Siluriformes: Trichomycteridae) and re-description of Trichomycterus itatiayae Maria Anaïs Barbosa and Wilson J. E. M. Costa Laboratório de Ictiologia Geral e Aplicada, Departamento de Zoologia, Universidade Federal do Rio de Janeiro, Cidade Universitária, Caixa Postal 68049, CEP , Rio de Janeiro, RJ, Brasil. s: anaisbarbosa@yahoo.com.br; wcosta@acd.ufrj.br Received: 19 February 2008 Accepted: 22 July 2008 Abstract Trichomycterus nigroauratus n. sp. is described from south-eastern Brazil and Trichomycterus itatiayae is redescribed. Trichomycterus nigroauratus differs from all the remaining species of Trichomycterus by possessing golden spots on its snout and body. The species seems to be closely related to T. itatiayae, based on the presence of a broad metapterygoid, which is wider than long, and colour pattern that exhibits a black stripe along the lateral midline, which posteriorly reaches the caudal fin posterior margin, at least in juveniles. Trichomycterus nigroauratus differs from T. itatiayae mainly by the number of rays on the pectoral fin, the related position of the anal fin, the morphology of the opercular and interopercular odontodes, the autopalatine and urohyal bones, the caudal fin and by its colour pattern. Trichomycterus diabolus also has a broad metapterygoid but seems to be closely related to T. castroi, with which it shares a distinctive unpigmented area on the basal region of the caudal fin. Trichomycterus nigroauratus and T. itatiayae are often found together living syntopically in small mountain rivers of the region, swimming close to the substrate during daylight. Resumo Trichomycterus nigroauratus, espécie nova, do sudeste do Brasil é descrita e Trichomycterus itatiayae é redescrita. Trichomycterus nigroauratus, espécie nova, difere de todas as espécies restantes de Trichomycterus por possuir pintas douradas no focinho e no corpo. A espécie parece estar relacionada à T. itatiayae baseado na presença de um amplo metapterigóide, que é mais largo do que alto, e padrão de colorido apresentando uma listra negra ao longo da linha média lateral, que posteriormente alcança a margem posterior da nadadeira caudal, pelo menos nos juvenis. Trichomycterus nigroauratus difere de T. itatiayae principalmente pelo número de raios da nadadeira peitoral, posição relativa da nadadeira anal, morfologia dos odontódeos operculares e interoperculares, morfologia dos ossos palatino e urohial, morfologia da nadadeira caudal e pelo padrão de colorido. Trichomycterus diabolus também apresenta um amplo metapterigóide, mas parece estar mais intimamente relacionada a T. castroi, com a qual compartilha uma inconfundível área não pigmentada sobre a margem proximal da nadadeira caudal. Trichomycterus nigroauratus e T. itatiayae são freqüentemente encontradas juntas, vivendo em sintopia, nas pequenas drenagens de montanha da região, nadando próximas ao substrato, durante o dia. Zusammenfassung Trichomycterus nigroauratus n. sp. aus SO-Brasilien wird erstmals, Trichomycterus itatiayae eine zweites Mal in revidierter Fassung beschrieben. Trichomycterus nigroauratus unterscheidet sich von allen anderen Arten der Gattung durch goldene Flecken auf Schnauze und Rumpf. Die Art ist offenbar nahe verwandt mit T. itatiayae, beide haben ein breites Metapterygoid, das breiter als lang ist, und in ihrem Farbmuster einen schwarzen Streifen entlang der seitlichen Mittellinie, der nach hinten zu den hinteren Rand der Schwanzflosse erreicht, zumindest bei jungen Tieren. Trichomycterus nigroauratus unterscheidet sich von T. iatiayae hauptsächlich durch die Zahl der Flossenstrahlen in der Brustflosse, eine entsprechende Stellung der Afterflosse, durch die Gestalt der opercularen und interopercolaren Odontoden (der Stacheln auf Kiemendeckel und Zwischenkiemendeckel) sowie der Knochen Autopalatinum und Urohyale und der Schwanzflosse, außerdem durch das Farbmuster. Trichomycterus diabolus besitzt ebenfalls ein breites Metapterygoid, ist aber offenbar mit T. castroi näher verwandt, mit dem es einen deutlichen unpigmentierten Bereich im Basalteil der Schwanzflosse gemeinsam hat. Trichomycterus nigroauratus und T. itatiayae findet man oft syntopisch zusammenlebend in kleinen Bergflüssen jener Region, wo sie bei Tageslicht dicht über dem Substrat schwimmen. Résumé Trichomycterus nigroauratus n. sp. est décrit, originaire du sud-est brésilien, et Trichomycterus itatiayae est redécrit. Trichomycterus nigroauratus se distingue de toutes les autres espèces de Trichomycterus par la présence de taches dorées sur le rostre et sur le corps. L espèce semble très proche de 175 aqua vol. 14 no October 2008

2 Description of a n. sp. of catfish from the upper rio Paraíba do Sul basin, south-eastern Brazil and re-description of Trichomycterus itatiayae T. itatiayae par la présence d un large os métaptérygoïde, plus large que long, et d un patron de coloration qui montre une ligne noire le long de la ligne latérale, qui à l arrière va jusqu à la marge postérieure de la caudale, du moins chez les juvéniles. Trichomycterus nigroauratus se distingue de T. itatiayae surtout par le nombre de rayons de la pectorale, par la position de l anale, par la morphologie des odontodes operculaires et interoperculaires, par l os autopalatin et l os urohyal, par la caudale et par le patron de coloration. Trichomycterus diabolus possède aussi un large os métaptérygoïde, mais semble plus apparenté à T. castroi avec lequel il partage une zone non pigmentée remarquable sur la région basale de la caudale. Trichomycterus nigroauratus et T. itatiayae sont souvent trouvés ensemble, vivant de façon syntopique dans de petits cours d eau de montagne de la région nageant près du substrat à la lumière du jour. Sommario Si descrive Trichomycterus nigroauratus come nuova specie originaria del Brasile sudorientale e si fornisce una nuova descrizione di Trichomycterus itatiayae. Trichomycterus nigroauratus differisce da tutte le alter specie di Trichomycterus per possedere macchie dorate sul muso e sul corpo. La specie appare strettamente imparentata a T. itatiayae in base alla presenza di un esteso metapterigoide, più ampio in larghezza che in lunghezza, e per la colorazione che si caratterizza per una stria nera lungo la linea mediana laterale che raggiunge il margine posteriore della pinna caudale, almeno negli individui giovani. Trichomycterus nigroauratus differisce da T. itatiayae principalmente per il numero di raggi della pettorale, la posizione relativa della pinna anale, la morfologia degli odontodi opercolari e interopercolari, l autopalatino e le ossa uroiali, la pinna caudale e la livrea. Anche T. diabolus ha un largo metapterigoide ma appare più vicino a T. castroi, con cui condivide una caratteristica area depigmentata nella regione basale della caudale. Trichomycterus nigroauratus e T. itatiayae sono spesso raccolti insieme, poiché abitano gli stessi piccoli torrenti di montagna della regione ed entrambi nuotano presso il fondale durante il giorno. INTRODUCTION Trichomycterus Valenciennes, 1832 is the most diversified trichomycterid genus with over 110 nominal species (Ferraris Jr. 2007), occurring in most drainage basins of South America and southern Central America. They usually are endemic to small areas of mountain rivers, which are vulnerable to environmental change, thus necessitating prompt taxonomic work. A high concentration of species of Trichomycterus has been recorded in south-eastern Brazil (Eigenmann 1918, Costa 1992). This region has been explored intensively since the early nineteenth century, but many localized areas in the upper mountain streams remain insufficiently researched. Recent efforts directed to sampling fishes in mountain streams revealed the occurrence of many undescribed species of Trichomycterus in south-eastern Brazil (Barbosa & Costa 2003a, b; Alencar & Costa 2004; Bockmann et al. 2004; Lima & Costa 2004). A new species from the upper rio Paraíba do Sul basin, with a remarkable, distinctive colour pattern, is herein described, and Trichomycterus itatiayae Miranda Ribeiro, 1906 from the same region is re-described. MATERIALS AND METHODS Samples were collected with dip nets during daylight. Measurements and counts follow Barbosa & Costa (2003b). Measurements are presented as percentages of standard length (SL), except for subunits of the head, which are presented as percentages of head length (HL). Counts of procurrent caudal fin rays, vertebrae, branchiostegal rays, teeth and odontodes were made only in cleared and stained specimens (c&s) prepared according to Taylor & Van Dyke (1985). Morphological data for T. maracaya are based on the literature (Bockmann et al. 2004). Abbreviations used for institutions are: FMNH, Field Museum of Natural History, Chicago; MNHN, Muséum National d Histoire Naturelle, Paris; UFRJ, Universidade Federal do Rio de Janeiro, Rio de Janeiro; MNRJ, Museu Nacional do Rio de Janeiro, Rio de Janeiro. Trichomycterus nigroauratus n. sp. (Fig. 1) Holotype: UFRJ 6034, 50.1 mm SL, Brazil: Estado de São Paulo: Município de São José do Barreiro: Cachoeira da Usina, rio do Barreiro, tributary of rio Paraíba do Sul basin, S W, altitude about 600 m, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 21 January Paratypes: Brazil: Estado de São Paulo: Município de São José do Barreiro, rio Paraíba do Sul basin: UFRJ 5689, 7 ex., mm SL; UFRJ 7585, 6 ex., mm SL, collected with Holotype; UFRJ 5248, 36 ex., mm SL, UFRJ 5691, 10 ex., mm SL (c&s), same locality, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 25 March Município de Piquete: UFRJ 5692, 7 ex., mm SL; ribeirão Piquete, S W, altitude 795 m, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 19 January aqua vol. 14 no October

3 Maria Anaïs Barbosa and Wilson J. E. M. Costa Table I. Morphometric data of T. nigroauratus n. sp. (UFRJ6034) and T. itatiayae Miranda Ribeiro. H = holotype. T. nigroauratus T. itatiayae (n=10) (n=4) H Range Range SL [mm] In percent of standard length Body depth Caudal peduncle depth Body width Caudal peduncle width Dorsal fin base length Anal fin base length Pelvic fin length Distance between pelvic fin bases Pectoral fin length Predorsal length Prepelvic length Head length In percent of head length Head depth Head width Interorbital width Preorbital length Eye diameter ; UFRJ 705, 3 ex., mm SL, UFRJ 5166, 1 ex., 48.8 mm SL (c&s); UFRJ 5594, 3 ex., mm SL (c&s), rio Benfica, 2 km N of Piquete, W. J. E. M. Costa & U. Neira, 2 December 1991; UFRJ 5048, 8 ex mm SL, UFRJ 5167, 2 ex., mm SL (c&s), rio Benfica, city of Piquete; W. J. E. M. Costa & M. A. Barbosa, April 1998; UFRJ 662, 4 ex., mm SL; UFRJ 4552, 1 ex., 77.9 mm SL (c&s), tributary of rio Banquete, W. J. E. M. Costa & U. Neira, 2 December Estado do Rio de Janeiro, rio Paraíba do Sul basin: Município de Itatiaia: UFRJ 597, 2 ex., mm SL, W. J. E. M. Costa & C. P. Bove, 10 November 1991; UFRJ 5690, 2 ex., mm SL, rio Campo Belo, S W, altitude 492 m, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 24 January 2003; UFRJ 4068, 1 ex., 31.4 mm SL, rio das Pedras, Três Cachoeiras, Penedo, F. Pupo, 21 November Município de Resende: UFRJ 5154, 1 ex., 38.2 mm SL (c&s), small stream in Serrinha, tributary of rio Alambari, S W, altitude 663 m, W. J. E. M. Costa, 17 June Diagnosis: Distinguished from all other species of the genus from south-eastern Brazil by the unique Fig. 1. Trichomycterus nigroauratus, UFRJ 6034, live holotype, 50.1 mm SL; Brazil: São Paulo: Município de São José do Barreiro. Photo by W. J. E. M. Costa 177 aqua vol. 14 no October 2008

4 Description of a n. sp. of catfish from the upper rio Paraíba do Sul basin, south-eastern Brazil and re-description of Trichomycterus itatiayae colour pattern in living specimens, consisting of golden spots on the snout, flank, above and below the midline, and the dorsum; similar to T. itatiayae and T. diabolus Bockmann, Casatti & de Pinna, 2004 and distinguished from all other species from south-eastern Brazil by possessing a broad metapterygoid, which is wider than long (Figs 2-3); distinguished from T. itatiayae by having eight pectoral fin rays (vs seven), anal fin origin posterior to dorsal fin base, between base of dorsal fin rays 9-12 (vs through middle of dorsal fin base, between base of dorsal fin rays 7-8), opercular and interopercular odontodes conical (vs incisiform), opercular odontodes (vs 10-15), presence of first two infraorbital pores (vs. absence), caudal fin subtruncate (vs rounded), smaller predorsal length ( % SL, vs % SL) and larger eye (eye diameter % of head length, vs % of head length); distinguished from T. diabolus by the absence of the bony contact area between metapterygoid and quadrate (vs presence), moderate pectoral fin filament, about 20% of pectoral fin length (vs pectoral fin filament absent), barbels well developed, tip reaching between posterior margin of interopercular patch of odontodes and pectoral fin base (vs barbels short, tip never reaching beyond anterior margin of interopercular patch of odontodes), smaller head length ( % SL, vs % SL), absence of white and black bars on caudal fin (vs presence) and colour pattern with a broad black stripe on the flank (vs absence of stripe). Description: Morphometric data for holotype and paratypes given in Table I. Body moderately deep, subcylindrical on anterior portion, compressed on caudal peduncle; dorsal profile slightly Fig. 2. Left jaw suspesorium and opercular series of Trichomycterus nigroauratus, UFRJ 5691, lateral view. Abbreviations: H, hyomandibula; I, interopercle; M, metapterygoid; O, opercle; P, preopercle; Q, quadrate. aqua vol. 14 no October

5 Maria Anaïs Barbosa and Wilson J. E. M. Costa convex between snout and end of dorsal fin base, straight to slightly convex on caudal peduncle; ventral profile straight to slightly convex between lower jaw and end of anal fin base, straight on caudal peduncle; greatest body depth in vertical immediately in front of pelvic fin origin; skin papillae minute; urogenital papilla spherical, at level of anterior third of dorsal fin base; dorsal and anal fins approximately triangular; dorsal fin origin between centra of seventeenth and nineteenth vertebrae; anal fin origin at level of base of dorsal fin rays 9 to 12 and between centrum of twentysecond and twentythird vertebrae; pectoral fin approximately triangular, lateral and posterior edges slightly convex; first pectoral fin ray terminating in short filament, about 20% of pectoral fin length; pelvic fin shorter than anal fin, not covering urogenital pore, tip not reaching anal fin, in vertical just anterior to dorsal fin origin; pelvic fin bases separated by interspace; pelvic fin origin at level of centra of sixteenth or seventeenth vertebra; caudal fin subtruncate; dorsal fin rays 11-12; anal fin rays 10-11; pectoral fin rays 8; pelvic fin rays 5; caudal fin principal rays 13, dorsal procurrent rays 14-17, ventral procurrent rays 11-13; total vertebrae 35-36; pleural ribs 13-14; upper hypural plates separated, dorsal plate slightly wider than ventral plate. Head subtriangular in dorsal view; snout blunt; mouth subventral; maxilla shorter than premaxilla; teeth incisiform in outer rows, conic in innermost row; eye at middle of head or slightly nearer to snout than to posterior edge of head; barbels well developed; tip of nasal barbel reaching anterior portion of opercular patch of odontodes; tip of maxillary barbel reaching between anterior portion of opercular patch of odontodes and pectoral fin Fig. 3. Left jaw suspesorium and opercular series of Trichomycterus itatiayae, UFRJ 5155, lateral view. Abbreviations: H, hyomandibula; I, interopercle; M, metapterygoid; O, opercle; P, preopercle; Q, quadrate. 179 aqua vol. 14 no October 2008

6 Description of a n. sp. of catfish from the upper rio Paraíba do Sul basin, south-eastern Brazil and re-description of Trichomycterus itatiayae base; tip of rictal barbel reaching posterior region of interopercular patch of odontodes; 7 or 8 branchiostegal rays; interopercular odontodes 38-40; opercular patch of odontodes wide, with 16-18; conical odontodes; opercular odontodes about equal in width to interopercular odontodes; opercular odontodes arranged approximately in a vertical line; medial margins of autopalatine slightly concave; posterior process of autopalatine about equal in length to autopalatine without posterior process; lacrimal about one fourth supraorbital length; supraorbital rod-shaped; metapterygoid moderate in size, broad, without distinct processes; anterodorsal surface of hyomandibula with weak concavity; urohyal foramen elliptical, usually 8- shaped; distal portion of lateral arm of urohyal truncate. Supraorbital canal continuous, with three pores; first pore in transverse line through anterior nostril, second in transverse line just posterior to posterior nostril, third supraorbital pore paired, each pore nearer to symmetrical pore than to orbit in transverse line just posterior to orbit; infraorbital divided into two sections, each with two pores; first infraorbital pore in transverse line through anterior nostril, second in transverse line just anterior to posterior nostril, third and fourth posterior to orbit; preopercular canal with one pore, at level of anterior margin of opercular patch of odontodes; lateral line on body short, with three pores, posteriormost pore just posterior to pectoral fin base. C o l o r a t i o n : Side of body and head light purplish brown, with dark grey to black stripe along lateral midline between opercular region and caudal peduncle end, sometimes interrupted; row of horizontally elongated golden spots above and below midline, and along dorsum; laterodorsal row of coalesced grey spots; lateroventral row of dark grey to black dots or round spots; venter yellowish white; dark grey to black stripe between nasal barbel and eye; round golden spot on middle of snout, and another similar but smaller anterior to nasal barbel; nasal barbel dark grey to black, maxillary and rictal barbels light grey; iris light yellow; fins yellow, rays dark grey to black; pectoral fin filament white; in juveniles, black stripe along lateral midline, dark pigmentation extending to posterior margin of caudal fin, and faint grey spots on dorsum. Distribution: Upper Barreiro River drainage basin, serra da Bocaina, and upper Piquete, Pirapitinga, Alambari, Pedras, Bonito, and Campo Belo River drainage basins, serra da Mantiqueira, upper rio Paraíba do Sul basin, south-eastern Brazil. Habitat: Juveniles and adults were observed and collected swimming actively during daylight, usually in still water pools, close to the bottom, on the litter, never in places with higher current velocities. Specimens were collected between 20 and 150 cm depth, in pools in clearwater streams with fast flowing water, and sandy and gravel substrate (Fig. 4). Etymology: From the Latin nigro (black) and auratus (golden), referring to the colour pattern of the new species. Fig. 4. Brazil: São Paulo: São José do Barreiro, cachoeira da Usina, rio Barreiro, type locality of Trichomycterus nigroauratus. Photo by W. J. E. M. Costa aqua vol. 14 no October

7 Maria Anaïs Barbosa and Wilson J. E. M. Costa Trichomycterus itatiayae Miranda Ribeiro, 1906 (Figs 5-6) Trichomycterus brasiliensis itatiayae Miranda Ribeiro, 1906: 177, pl.1 (Figs a-c), original description, ribeirões do Prudencio and Tapera, tributaries of ribeirão Bonito, tributary of Parahyba [Paraíba], Mont Serrat, Itatiaya [Itatiaia], Rio de Janeiro, Brazil [approximately S W]. (Lectotype: MNRJ 792, designated by Caramaschi & Caramaschi, 1991). Material examined: Brazil: Rio de Janeiro: MNRJ 792, 67.0 mm SL, lectotype; MNRJ 11346, 1 paralectotype; MNRJ 11347, 1 paralectotype, Itatiaia, Mont Serrat, rio Paraíba do Sul basin, ribeirões do Prudencio and Papera, collected by Prof. C. Moreira, August Município de Resende, Serrinha: UFRJ 5139, 3 ex., mm SL, UFRJ 5155, 2 ex., mm SL (c&s), Poço das Esmeraldas, approximately S W, W. J. E. M. Costa, C. P. Bove & B. B. Costa, 18 June 2000; UFRJ 5667, 5 ex., mm SL, Poço Dourado, rio Santo Antônio, tributary of rio Pirapitinga, S W, altitude 700 m, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 19 January 2003; UFRJ 5222, 1 ex., mm SL (c&s), small stream, tributary of rio Alambarí, rio Paraíba do Sul basin, S W, altitude 663 m, collected by W. J. E. M. Costa, 17 June Município de São José do Barreiro: UFRJ 5668, 4 ex., mm SL; cachoeira da Usina, São José do Barreiro, S W, altitude 600 m, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 21 January Município de Itatiaia: UFRJ 5669, 2 ex., mm SL, Itatiaia, rio Campo Belo, S W, altitude 492 m, W. J. E. M. Costa, B. B. Costa & C. P. Bove, 24 January Diagnosis: Similar to T. nigroauratus and T. diabolus and distinguished from all other species of south-eastern Brazil by possessing a broad metapterygoid, which is wider than long (Figs 2-3). Fig. 5. Trichomycterus itatiayae, UFRJ 5668, live specimen, 58.5 mm SL; Brazil: São Paulo: São José do Barreiro. Photo by W. J. E. M. Costa Fig. 6. Trichomycterus itatiayae, UFRJ 5668, live specimen, 25.2 mm SL; Brazil: São Paulo: São José do Barreiro. Photo by W. J. E. M. Costa 181 aqua vol. 14 no October 2008

8 Description of a n. sp. of catfish from the upper rio Paraíba do Sul basin, south-eastern Brazil and re-description of Trichomycterus itatiayae Easily distinguished from T. nigroauratus and T. diabolus by possessing: 7 pectoral fin rays (vs 8), opercular and interopercular odontodes incisiform (vs conical), posterior process of autopalatine about one fourth length of autopalatine without posterior process (vs about equal in length to autopalatine without posterior process); also distinguished from T. nigroauratus by possessing distal portion of lateral arm of urohyal pointed (vs truncate), anal fin origin at level of middle of dorsal fin base, between base of dorsal fin rays 7-8 (vs at level of posterior portion of dorsal fin base, between base of dorsal fin rays 9-12), interopercular odontodes (vs 38-40), opercular odontodes (vs 16-18), absence of first two infraorbital pores Fig. 7. Urohyal of Trichomycterus nigroauratus (A), UFRJ 5167 and Trichomycterus itatiayae (B), UFRJ (vs presence) and from T. diabolus by possessing dorsal fin rays (vs 12), nine anal fin rays (vs 10), first pectoral fin ray terminating in short filament, about 15% of pectoral fin length (vs without any filament), barbels well developed, tip reaching beyond posterior margin of opercular patch of odontodes (vs barbels short, tip never reaching beyond anterior margin of interopercular patch of odontodes), absence of vertical unpigmented band across the proximal region of caudal fin (vs presence) and absence of the bony contact area between metapterygoid and quadrate (vs presence). It also differs from all other congeners by the short posterior process of autopalatine, about one fourth length of autopalatine without posterior process (Fig. 8) (vs about as long as autopalatine without posterior process), and U-shaped deep concavity on the anterodorsal margin of hyomandibula (Fig. 3) (vs weak concavity). Description: Morphometric data are given in Table I. Body moderately deep, subcylindrical on anterior portion, compressed on caudal peduncle; dorsal profile slightly convex between snout and end of dorsal fin base, straight to slightly convex on caudal peduncle; ventral profile straight to slightly convex between lower jaw and end of anal fin base, straight on caudal peduncle; greatest body depth immediately in front of pelvic fin origin; skin papillae minute; urogenital papilla spherical, at level of anterior third of dorsal fin base; dorsal and anal fins approximately triangular; dorsal fin origin in vertical between centrum of eighteenth and twentieth vertebrae; anal fin origin at level of base of dorsal fin ray 7 and 8 and between centrum of twentysecond and twentythird vertebrae; pectoral fin about triangular, lateral and posterior edges slightly convex; first pectoral fin ray terminating in short filament, about 15% of pectoral fin length; pelvic fin shorter than anal fin, covering urogenital pore, tip not reaching anal fin, in vertical just anterior to dorsal fin origin; pelvic fin bases separated by interspace; pelvic fin origin in vertical through centrum of sixteenth or eighteenth vertebra; caudal fin rounded; dorsal fin rays 10-11; anal fin rays nine; pectoral fin rays seven; pelvic fin rays five; caudal fin principal rays 13, dorsal procurrent rays 13-16, ventral procurrent rays 11-12; total vertebrae 35-37; pleural ribs 13-14; upper hypural plates separated, dorsal plate wider than ventral plate. Head trapezoidal or elliptical in dorsal view; snout blunt; mouth subventral; maxilla shorter aqua vol. 14 no October

9 Maria Anaïs Barbosa and Wilson J. E. M. Costa than premaxilla; teeth incisor; eye at middle of head or slightly nearer to snout than to posterior edge of head; barbels well developed; tip of nasal barbel reaching between anterior portion and middle of opercular patch of odontodes; tip of maxillary barbel reaching between middle of opercular patch of odontodes and pectoral fin base; tip of rictal barbel reaching posterior region of interopercular patch of odontodes; eight branchiostegal rays; interopercular odontodes 28-34; opercular patch of odontodes moderate in width, with 10-15; incisiform odontodes; opercular odontodes about equal in width to interopercular odontodes; opercular odontodes arranged approximately in a vertical line; medial margin of autopalatine slightly concave; posterior process of autopalatine about one fourth length of autopalatine without posterior process; lacrimal about one fourth supraorbital length; supraorbital rod-shaped; metapterygoid large and wide, without distinct processes; anterodorsal surface of hyomandibula with deep, U-shaped concavity; urohyal foramen circular; distal portion of lateral arm of urohyal pointed. Supraorbital canal continuous, with three pores; first pore in transverse line through anterior nostril, second in transverse line just posterior to posterior nostril, third supraorbital pore paired, each pore about equidistant from symmetrical pore and orbit; anterior section of infraorbital canal absent; preopercular canal with one pore, at level of anterior margin of opercular patch of odontodes; lateral line of body short, with three pores, posteriormost pore in vertical just posterior to pectoral fin base. C o l o r a t i o n : Side of body and head light yellowish grey, with black stripe along lateral midline between opercular region and caudal peduncle end, sometimes, in larger specimens, stripe substituted by coalesced small spots and vermiculated marks; dark grey small spots on dorsum, and above and below lateral stripe; venter yellowish white; dark grey stripe between nasal barbel and eye; nasal barbel dark grey, maxillary and rictal barbels light grey; iris grey; fins yellowish hyaline with brown dots on their bases; pectoral fin filament white; in juveniles, black lateral stripe extending to caudal fin posterior margin, with faint grey spots on dorsum. Fig. 8. Left autopalatine of Trichomycterus nigroauratus (A), UFRJ 5167 and Trichomycterus itatiayae (B), UFRJ Abbreviation: pp, posterior process. 183 aqua vol. 14 no October 2008

10 Description of a n. sp. of catfish from the upper rio Paraíba do Sul basin, south-eastern Brazil and re-description of Trichomycterus itatiayae Distribution: Upper Pirapitinga, Alambari, Pedras, Bonito, and Campo Belo River drainage basins, serra da Mantiqueira, and Barreiro River drainage basin, serra da Bocaina, upper rio Paraíba do Sul basin, south-eastern Brazil. Habitat: All collecting sites were clearwater streams with fast flowing water and pools of quiet water. Both juveniles and adults were easily seen, actively swimming close to the substrate during daylight, both close to the stream bank at about 5 cm depth and in the middle stream channel at about 2 m depth, in still water. It was abundant at higher altitudes ( m), in areas with greenish hyaline water and rocky substrate, where it was the only trichomycterid found. It was rare in streams at about m above sea level, with gravel substrate, and where other trichomycterids were abundant (T. nigroauratus and T. travassosi Miranda Ribeiro, 1949). In the latter situation, since juveniles of T. itatiayae and T. nigroauratus possess similar colour patterns, identification of live specimens is only possible after careful examination. Juveniles and adults of T. nigroauratus and T. travassosi were observed and collected swimming actively during daylight, usually in still water pools, close to the bottom, on the litter, never in places with higher current velocities. Specimens were collected between 20 and 150 cm deep, in streams with sandy and gravel substrate. Discussion: Miranda Ribeiro (1906) reported on three specimens of the trichomycterid genus Trichomycterus, collected in the mountain streams of Itatiaia, Rio de Janeiro, Brazil, (deposited in MNRJ), which were considered to be a variety of Trichomycterus brasiliensis Lütken, 1874 (T. brasiliensis itatiayae). However, he stated that these specimens were different from T. brasiliensis, in possessing a black longitudinal broad stripe on the side of the body, as the most remarkable distinctive feature. Subsequently Eigenmann (1918) established Pygidium (=Trichomycterus) itatiayae as a valid species, providing a short diagnosis. Later, Caramaschi & Caramaschi (1991) examined the type specimens of T. itatiayae, recognizing its validity, and designated a lectotype and paralectotypes. Trichomycterus brasiliensis is a member of a species group diagnosed by a color pattern consisting of numerous small spots scattered over its body side, and some derived osteological characters, always absent in T. itatiayae and in other congeners (Barbosa & Costa 2003). Trichomycterus itatiayae also differs from T. brasiliensis in having the bases of its pelvic fin separated by an interspace (vs in close proximity, sometimes in contact), nine branchiostegal rays (vs eight), dorsal procurrent rays (vs 19-22) and ventral procurrent rays (vs 14-17). Trichomycterus nigroauratus and T. itatiayae are often syntopic species found at the upper section of mountain streams of the Itatiaia region. Both species have a black stripe on the flank, and may be easily confused when juvenile. However, adult individuals of T. nigroauratus have golden spots on the body and snout, whereas such spots are never found in T. itatiayae; whereas in the latter, the stripe becomes broken to form spots in older specimens, a colour pattern never occurring in T. nigroauratus. Preserved specimens of both species may be easily distinguished by counting pectoral fin rays (eight rays in T. nigroauratus, seven rays in T. itatiayae), and observing the relative position of dorsal and anal fins (anal fin origin at level of posterior portion of dorsal fin base in T. nigroauratus, through middle of dorsal fin base in T. itatiayae), the morphology of opercular and interopercular odontodes (conical in T. nigroauratus, incisiform in T. itatiayae), the morphology of the posterior process of the autopalatine (lengthened in T. nigroauratus, short in T. itatiayae), the morphology of the distal portion of the lateral arm of the urohyal (truncate in T. nigroauratus, pointed in T. itatiayae), presence of the first two infraorbital pores (present in T. nigroauratus, absent in T. itatiayae), and the caudal fin morphology (subtruncate in T. nigroauratus, rounded in T. itatiayae). Both T. nigroauratus and T. itatiayae possess a large metapterygoid, a condition contrasting to most other congeners. However, T. diabolus, from the Paranapanema River basin, also has a broad metapterygoid as reported by Bockmann et al. (2004). On the other hand, T. diabolus was considered to be closely related to T. castroi Pinna, 1992, from the Iguaçu River basin, by both having a conspicuous unpigmented area on the basal region of the caudal fin (Bockmann et al. 2004), a colour pattern occurring neither in T. nigroauratus nor in T. itatiayae. Unfortunately, no data of metapterygoid morphology is available for T. castroi, a species poorly represented in ichthyological collections. Comparative material: Trichomycterus albinotatus Costa, 1992: MZUSP 42312, holotype, 46.3 mm CP; MZUSP 42315, 3 ex., UFRJ 547, 8 ex., UFRJ 583, 2 ex. (c&s) UFRJ 593, 4 ex., UFRJ 594, 1 ex., aqua vol. 14 no October

11 Maria Anaïs Barbosa and Wilson J. E. M. Costa UFRJ 1299, 18 ex., UFRJ 631, 1 ex., UFRJ 4657, 11 ex., UFRJ 5628, 3 ex. (c&s); T. alternatus Eigenmann 1917: UFRJ 080, 6 ex., UFRJ 556, 2 ex. (c&s), UFRJ 5673, 1 ex. (c&s), UFRJ 836, 2 ex.; T. auroguttatus Costa, 1992: MZUSP 43341, holotype, 52.1 mm SL, MZUSP 43342, 4 paratypes, mm SL, UFRJ 640, 2 ex., UFRJ 611, 4 ex., UFRJ 610, 3 ex., UFRJ 3364, 1 ex., UFRJ 3365, 6 ex., UFRJ 4562, 4 ex. (c&s), UFRJ 1302, 2 ex., UFRJ 4101, 4 ex., UFRJ 4558, 2 ex. (c&s); T. brasiliensis: MNHN 0303, 1 ex. (photograph and X-rays), UFRJ 4833, 5 ex., UFRJ 4834, 3 ex. (c&s), UFRJ 4923, 2 ex., MNHN 9575, 1 ex. (photograph); T. candidus (Ribeiro, 1949): MNRJ 5209, holotype, 60.5 mm SL, MNRJ 11762, 14 paratypes, mm SL, MNRJ 5356, 21 ex., UFRJ 4926, 31 ex., UFRJ 4928, 5 ex. (c&s); T. caudofasciatus Alencar & Costa, 2004: UFRJ 6002, holotype, 48.5 mm SL, MCP 35030, 2 paratypes, mm SL, UFRJ 5655, 10 paratypes, mm SL, UFRJ 5656, 5 paratypes (c&s), mm SL; T. concolor Costa, 1992 : MZUSP 42206, 1 ex. (c&s); T. florensis Ribeiro, 1943: UFRJ 595, 9 ex., UFRJ 646, 1 ex. (c&s), UFRJ 5463, 1 ex.; T. giganteus Lima & Costa, 2004: UFRJ 599, holotype, mm SL; MCP 35028, 4 paratypes, mm SL, UFRJ 5730, 10 paratypes, mm SL, UFRJ 5732, 2 paratypes (c&s), mm SL; T. goeldii Boulenger, 1896: UFRJ 1063, 3 ex., UFRJ 5434, 2 ex. (c&s), UFRJ 1064, 1 ex.; T. hasemani Eigenmann, 1914: USNM , 2 ex. (c&s); T. immaculatus (Eigenmann & Eigenmann, 1889): UFRJ 3593, 1 ex., MNRJ 16515, 3 ex., UFRJ 0082, 2 ex., UFRJ 557, 3 ex., UFRJ 420, 6 ex.; T. itatiayae: UFRJ 5139, 3 ex., UFRJ 5155, 2 ex. (c&s), UFRJ 5667, 5 ex., UFRJ 5222, 1 ex. (c&s), UFRJ 5668, 4 ex., UFRJ 5669, 2 ex.; T. johnsoni (Fowler, 1932): UFRJ 3823, 31 ex.; T. longibarbatus Costa, 1992: MZUSP 43339, holotype, 58.4 mm SL; UFRJ 629, 1 paratype, 41.1 mm SL, MZUSP 23812, 17 paratypes, mm SL, UFRJ 3368, 5 ex., mm SL; UFRJ 5674, 3 ex. (c&s); T. mimonha Costa, 1992: MZUSP 43343, holotype, 59.3 mm SL, MZUSP 43344, 7 paratypes, mm SL, UFRJ 641, 7 paratypes, mm SL, UFRJ 5209, 1 ex. (c&s); T. mirissumba Costa, 1992: UFRJ 642, 3 paratypes, mm SL, UFRJ 4729, 12 ex., UFRJ 4730, 5 ex. (c&s); T. pantherinus Alencar & Costa, 2004: UFRJ 6001, holotype, 55.3 mm SL; MCP 35029, 6 paratypes, mm SL, UFRJ 56659, 22 paratypes, mm SL, UFRJ 5660, 6 paratypes (c&s), mm SL; T. potschi Barbosa & Costa, 2003: MCP 29061, holotype, 80.5 mm SL, UFRJ 4727, 11 paratypes, mm SL, MCP 29062, 2 paratypes, mm SL, UFRJ 4728, 5 ex. (c&s); T. reinhardti (Eigenmann, 1918): UFRJ 1149, 1 ex., UFRJ 5774, 1ex., UFRJ 1132, 1 ex., UFRJ 1144, 3 ex., UFRJ 4553, 3 ex. (c&s), UFRJ 5651, 2 ex. (c&s), UFRJ 580, 3 ex., UFRJ 644, 1 ex. (c&s), UFRJ 1297, 3 ex., UFRJ 4557, 1 ex. (c&s), UFRJ 1309, 3 ex., UFRJ 4555, 1 ex. (c&s), UFRJ 1313, 2 ex., UFRJ 1146, 1 ex.; T. travassosi: UFRJ 5670, 3 ex., UFRJ 596, 10 ex., UFRJ 4554, 3 ex. (c&s), UFRJ 4563, 1 ex. (c&s), UFRJ 5354, 4 ex. (c&s), UFRJ 5671, 8 ex., UFRJ 5140, 21 ex., UFRJ 5672, 22 ex.; T. variegatus Costa 1992: UFRJ 584, 9 ex., UFRJ 585, 2 ex. (c&s); T. vermiculatus (Eigenmann, 1918): FMNH 58077, holotype (photograph and X rays); T. zonatus (Eigenmann, 1918): UFRJ 1136, 17 ex., UFRJ 4549, 5 ex. (c&s), UFRJ 5321, UFRJ 5639, 2 ex. (c&s).. ACKNOWLEDGEMENTS We are especially grateful to Bruno Costa and Claudia Bove for their help during collecting trips. This study was supported by CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico Ministério de Ciência e Tecnologia) and FAPERJ (Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro). REFERENCES ALENCAR, A. R. & COSTA, W. J. E. M Description of two new species of the catfish genus Trichomycterus from southeastern Brazil (Siluriformes: Trichomycteridae). Zootaxa, 744: 1-8. BARBOSA, M. A. & COSTA, W. J. E. M. 2003a. Trichomycterus potschi (Siluriformes: Loricarioidei): a new trichomycterid catfish from coastal streams of southeastern Brazil. Ichthyological Exploration of Freshwaters, 14: BARBOSA, M. A. & COSTA, W. J. E. M. 2003b. Validade, relações filogenéticas e redescrição de Eremophilus candidus (Ribeiro, 1949) (Siluriformes: Trichomycteridae). Arquivos do Museu Nacional, 61: BOCKMANN, F. A., CASATTI, L. & DE PINNA, M. C. C A new species of trichomycterid catfish from Rio Paranapanema basin, southeastern Brazil (Teleostei: Siluriformes), with comments on the phylogeny of the family. Ichthyological Exploration of Freshwaters, 15: CARAMASCHI, E. P. & CARAMASCHI, U Taxonomic status of the trichomycterid catfish Trichomycterus itatiayae. Shorter contributions:ichthyology. Copeia, 1991 (1): aqua vol. 14 no October 2008

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