The geographic range of black-handed tamarins, which are endemic to Pará, Brazil, is limited by the Rio Amazonas (Amazon River) to the North, the Rio Tocantins (Tocantins River) to the East, the Rio Xingu (Xingu River) to the West,[5] and until recently, the Rio Gradaus (Gradaus River) to the South.[6] Photographic evidence of a black-handed tamarin in Confresa, a town in the northeastern region of the state of Mato Grosso, indicates an increase in the species' geographic range to the South.[7]