FIELDIANA Zoology Published by Field Museum of Natural History Volume 72, No. 3 December 19, 1977 Trachelyichthys exilis, A New Species of Catfish (Pisces: Auchenipteridae) from Peru DAVID W. GREENFIELD DEPARTMENT OF BIOLOGICAL SCIENCES NORTHERN ILLINOIS UNIVERSITY and DIVISION OF FISHES FIELD MUSEUM OF NATURAL HISTORY and GARRETT S. GLODEK DIVISION OF FISHES FIELD MUSEUM OF NATURAL HISTORY ABSTRACT Trachelyichthys exilis n. sp. is described from the Rio Mambn, Peru, on the basis of three specimens. The new species is the second known member of the genus Trachelyichthys previously known only from a single individual of T. decaradiatus from Surinam. T. exilis is compared with T. decaradiatus and a redescription of the latter is presented. RESUMEN So describe una nueva especie de la familia Auchenipteridae, Trachelyichthys exilis, basada en tres ejemplos desde el Rio Mam6n, Peru. Antes del descubrimiento de estos ejemplos, el genero Trachelyichthys se habia conocido por un solo ejemplo de su especie tipo, T. decaradiatus, describida por Mees (1974) desde Surinam. T. exilis se distingue de T. decaradiatus por tener la cabeza mas ancha y altas, la dis-tancia predorsal mas larga, la espina pectoral mas alargada, la placa dorsal mas ancha, el hocico mas corto, las bases de las aletas dorsal y anal mas largas, las bar-bas mandibulares exteriores y maxilares mas largas, y el proceso posterior del la elavicula de poca altura. Mees (1974) described the monotypic genus Trachelyichthys and its species T. decaradiatus on the basis of a single individual (56.5 mm. SL) taken in the Karanambo area, Rupununi, Surinam. On July 24, 1975 we collected three additional specimens of this genus US ISSN 0015-0754 Publication 1272 vw " 47 vJMIV 6( . .nnft University of Illinois A0"
BioStor
