The Long-tailed Potoo (Nyctibius aethereus) is a species of bird in the Nyctibiidae family. It is found in Brazil, Venezuela, Guyana, Colombia, Ecuador, Peru, Bolivia, and Paraguay; also in Argentina in the extreme northeast. Its natural habitat is subtropical or tropical moist lowland forests.

Range, western Amazon Basin--and South America

Western amazon basin

The core range of the Long-tailed Potoo is the contiguous region of the entire northwestern and southwestern Amazon Basin. In the north of South America, the range is in the eastern regions of Venezuela's Orinoco River drainage and the highlands bordering Guyana; in Guyana, the range extends into the eastern portions of the Essequibo River drainage to the border with Suriname. The contiguous range extends southward through Andean and Amazonian portions of Colombia, Ecuador and Peru.

The range in Bolivia is bifurcated; in the north, the Long-tailed Potoo is found on the headwater rivers to Brazil's Amazonas state's Madeira River; in northeastern Bolivia, the bifurcated range extends only to the mountain headwaters of another tributary of the Madeira, the Brazilian-Bolivia Guapore River.

Disjunct ranges

Two minor disjunct ranges occur, one on Pacific coastal Colombia, the other at the outlet islands of the Amazon River. The third major disjunct range occurs on coastal southeastern Brazil and inland into eastern Paraguay; the range is an 850km wide strip that extends about 2300 km, on the southeast side of Brazil's interior Cerrado region.