Curuá River (Iriri River tributary)  The Curuá River is a tributary of the Iriri River in Pará state in north-central Brazil. It is a tributary of the Iriri River. The river flows through the Tapajós-Xingu moist forests ecoregion. The river rises in the Nascentes da Serra do Cachimbo Biological Reserve, a strictly protected conservation unit established in 2005. It is one of the headwaters of the Xingu River. The upper part and the lower part of the Curuá River are divided by two waterfalls, only apart. The first waterfall is tall and the second is tall. As a consequence, the fauna in the upper part, above the waterfalls on the Serra do Cachimbo plateau, is highly distinct and includes several endemic fish: three "Lebiasina" species, "Brachychalcinus reisi", "Erythrocharax altipinnis", "Jupiaba kurua", "Knodus nuptialis", "Moenkhausia petymbuaba", "Leporinus guttatus", three "Harttia" species, three "Apistogramma" species (including "A. kullanderi", the largest in the genus), and others. These are to some extent protected by the reserve, but habitat loss continues and the proposed building of dams, which would remove the waterfalls that isolate the endemics from more widespread species in the lower part, potentially represents a serious threat.