 In the Amazon Basin, central Bolivia is the northwest range limit, the headwater tributaries to the north-northeast flowing Madeira River; the next range skips the Guaporé River, (a northwest-flowing tributary to the Madeira), eastwards on the Brazil–Bolivia border, and is next found at the headwaters of the Tapajós River, and joins on the east the extreme headwaters of the Xingu River.A disjunct range occurs downstream on the Tapajós and east towards the Xingu River, a block .Two other localized populations occur in the Amazon Basin, one on the Amazon River, the other on the downstream Madeira River.