Eastern pygmy marmoset

The eastern pygmy marmoset (Cebuella niveiventris) is a marmoset species, a very small New World monkey, found in the southwestern Amazon Rainforest in Bolivia, Brazil, Ecuador, and Peru. It was formerly regarded as conspecific with the similar western pygmy marmoset, but the eastern pygmy marmoset has whitish colored underparts. Although the eastern pygmy marmoset occurs further east than the western pygmy marmoset, the primary separators of their ranges are the Amazon River (Solimões River) and Maranon River, with the western occurring to the north of them and the eastern to the south. The species has recently been confirmed by DNA testing to exist in Ecuador, hundreds of kilometers north of the Maranon River.