The black-tailed marmoset (Mico melanurus) is dark brown with paler foreparts and a black tail. Unlike other marmosets, it has a stripe of yellow or white fur running down the thigh. Found in parts of the Amazon rainforest – it is native to Bolivia, Paraguay, and Brazil, east of the Rio Aripuana – the black-tailed marmoset is diurnal and arboreal, using its claws to climb trees, spending the night in tree hollows or in very close vegetation. Marmosets and their cousins, tamarins, are thought to be the most primitive monkeys.
