The common marmoset, also called white-tufted marmoset or white-tufted-ear marmoset, is a New World monkey. It originally lived on the northeastern coast of Brazil, in the states of Piaui, Paraiba, Ceará, Rio Grande do Norte, Pernambuco, Alagoas, and Bahia. Through release of captive individuals, it has expanded its range since the 1920s to Southeast Brazil, where it became an invasive species, raising concerns about genetic pollution of similar species, such as the buffy-tufted marmoset, and predation upon bird nestlings and eggs.

The buffy-tufted marmoset, also known as the buffy tufted-ear marmoset or white-eared marmoset, is a New World monkey that lives in the forests on the Atlantic coast of southeast Brazil. Of all the marmosets, it has the southernmost range.