The upper reached ichthyofauna of the Tiete River, Sao Paulo, Brazil: aspects of their diversity and conservation

Tiete River is one of the main rivers in the State of Sao Paulo, Brazil. It runs across this state from east to west for 1136 km. The upper reach of the Tiete River is located in the metropolitan region of the city of Sao Paulo where approximately 60% of the original Atlantic Forest remnants has been converted into rural and urban areas. Ichthyofauna of the upper reaches of the rivers is usually characterized by a high level of endemism, small fish with restricted geographic distribution. A qualitative survey of two main tributaries, Paraitinga and Biritiba Mirim Rivers, and a stretch of the Tiete River was carried out in order to ascertain their fish community composition, compare the former fish data collected in the same area and establish biodiversity conservation research programs. The fish fauna in the three riverine systems comprises 5 orders, 9 families, 20 genus and 28 species. One species, Glandulocauda melanogenys, out of sixteen regarded as strictly endemic to the upper reaches of the Tiete River according to previous data was found among the sampled collections. No established alien species were found despite their presence in the upstream reservoir of the Tiete Rivers. Human disturbances and their impacts on fish diversity are discussed, including their relation to the ecotone habitats.