Abstract. This study is a comprehensive review of fish fauna data for the Xingu River system. Information was compiled from seven field surveys (conducted between 2001 and 2002), bibliographic references, and museum collection records.
To provide data on the spatial distribution of fish species, the river basin was divided into six areas according to geographical and hydrological characteristics. Fish species from 14 orders and 47 families were recorded; the most diverse orders were Characiformes (210 species), Siluriformes (146 species), Perciformes (62 species) and Gimnotiformes (20 species). Of the 467 species identified, 69 were common to the whole river basin. Based on these results, two priority conservation areas were identified: 1) headwater rivers, which are characterized by a diverse range of small characid and cichlid species and intense anthropogenic disturbance, and 2) middle section of the Xingu, from its confluence with the Irirí River to its downstream waterfalls near Belomonte village. This region is characterized by a high diversity of Cichlidae, particularly Teleocichla, Anostomidae and Loricariidae families. Conserving these areas will help to maintain hydrological connectivity of the Xingu River system. Accepted 17 October 2004.