The first report of Sartor (Anostomidae) and Tatia intermedia (Auchenipteridae) for the Upper Tapajós River Basin are presented here. Sartor is very rare on collections, and is reported only from the Trombetas, Tocantins and Upper Xingu river basins. Tatia intermedia is registered in the upper reaches of the Araguaia, Tocantins, Xingu, and Capim rivers, tributaries of the lower Amazon River in Brazil, northwards to the Suriname coastal rivers and the Essequibo River in Guyana.