Mittermeier's Tapajós saki

Mittermeier's Tapajós saki (Pithecia mittermeieri) is a disputed species of saki monkey, endemic to west-central Brazil, south of the Amazon River between the Madeira and Tapajós rivers. A 2014 study split it from the Rio Tapajós saki on the basis of its pelage, and it is named for the primatologist Russell Mittermeier. A 2019 study found that the coat pattern used to separate it falls within the variation of the Rio Tapajós saki, so the American Society of Mammalogists tentatively treats the two as one, while the IUCN Red List and ITIS keep it as a species. Males are largely black with long white grizzling, white forearms and a bright orange ruff, and females are similar but less grizzled. Its range has shrunk because of human impacts, and most populations now lie south of the Aripuanã River in Mato Grosso. It is rated Vulnerable by the IUCN because of hunting, habitat loss, deforestation and fragmentation.