Iriri River Terra do Meio Ecological Station. The river varies greatly in volume depending on the season, and in the dry season include waterfalls, rocks and rapids. The Iriri River flows through the Tapajós-Xingu moist forests ecoregion. The river is rich in fish, including many species found only here and in the Xingu. Large sections remain unexplored due to its remoteness in a region surrounded by Amazon rainforest, and sections with strong current and cataracts. Iriri River The Iriri River () is a large tributary of the Xingu River in Brazil, in the state of Pará. It is long making it the
Xingu River in the Xingu River Basin and it is estimated that the total is around 600 fish species, including many endemics. At least 193 fish species living in rapids are known from the lower Xingu, and at least 26 of these are endemic. From 2008 to 2018 alone, 24 new fish species have been described from the river. Many species are seriously threatened by the dam, which will significantly alter the flow in the Volta Grande rapids. In the Upper Xingu region was a highly self-organized pre-Columbian anthropogenic landscape, including deposits of fertile agricultural terra preta, black soil in Portuguese, with