This study concerns in taxonomic survey on the anostomid species of the Uatuma River. It includes redescriptions and illustrations of all species found at the area The utilized material cames from an intensive fish survey program carried out at the Uatumã River drainage, in the area affected by the Balbina and Pitinga hydroelectric dams, boths in the Amazonas state. It is deposited at the icththyological collection of the Instituto Nacional de Pesquisas da Amazonia (INPA). Twenty two anostomid species were found in the Uatumã River drainage, belonging to eight genera, of which Leporinus were dominant, with twelve species, followed by Laemolyta, Anostomus, Anostomoides and Pseudanos (with two species) and Schizodon, Anostomoides, Synaptolaemus and Gnathodolus, with one species. Two species, Leporinus uatumaensis n.sp. and Leporinus pitingai n.sp. are considered new for science and here described. Diagnostic characters, distribution and habitat are cited; major ontogenetic changes in color patterns are also discussed. Several species had their distribution expanded.
Fishfauna; Amazon; Anostomidae