Two new Trichomycterus from Venezuela

[Silurus]

CA Lasso CA & F Provenzano, 2003. Two new species of catfish, genus <i>Trichomycterus</i> (Siluriformes : Trichomycteridae), from Gran Sabana, Guyana Shield, Venezuela. Revista de Biologia Tropical, 50: 1139-1149.

<i>Trichomycterus celsae</i> n. sp. and <i>Trichomycterus lewi</i> n. sp. are described from the river Kukenan a tributary of the river Caroni, Orinoco basin, Guyana Shield, Venezuela. The new species are diagnosed within the Guyana Shield <i>Trichomycterus</i> species by a distinctive color pattern. <i>Trichomycterus celsae</i> has a uniform light brown color on dorsum and sides of the body; the ventral surface is yellowish or creamy. <i>Trichomycterus lewi</i> has an irregular pattern of black spots of different sizes on dorsum and sides of the body, the larger spots are located at the posterior part of the body, and, the ventral surface is whitish. The osteology of the new species showed that they belong to the genus <i>Trichomycterus</i> . Osteological features support the external diagnosis of both species, some of them are: in <i>T. celsae</i> , the skull has the fontanels well separated, <i>T. lewi</i> has the fontanels closer and joined by a narrow canal. In <i>T. celsae</i> , the dorsal border of the hyomandibula has a conspicuous notch. In <i>T. lewi</i>, the metapterygoid has a projection on the posteroventral angle. Neural spine of the first preural centra is more elongated in <i>T. lewi</i> .