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-Tocantins-Araguaia moist forests 8 species of primates including the white-nosed saki ("Chiropotes albinasus"), red-handed tamarin ("Saguinus midas"), red-bellied titi ("Callicebus moloch"), Azara's night monkey ("Aotus azarae infulatus") and white-cheeked spider monkey ("Ateles marginatus"). The last two are endemic to this ecoregion and the Tapajós-Xingu moist forests to the west. Other species of mammals include white-lipped peccary ("Tayassu pecari"), collared peccary ("Pecari tajacu"), cougar ("Puma concolor"), jaguar ("Panthera onca"), South American tapir ("Tapirus terrestris"), brocket deer (genus "Mazama"), bare-tailed woolly opossum ("Caluromys philander"), and seven-banded armadillo ("Dasypus septemcinctus"). Endangered mammals include white-cheeked spider monkey ("Ateles marginatus"), black bearded saki ("Chiropotes satanas") and giant otter