The black-tufted marmoset, also known as Mico-estrela in Portuguese, is a species of New World monkey that lives primarily in the Neo-tropical gallery forests of the Brazilian Central Plateau. It ranges from Bahia to Paraná, and as far inland as Goiás, between 14 and 25 degrees south of the equator, and can commonly be seen in the City of Rio de Janeiro where it was introduced. This marmoset typically resides in rainforests, living an arboreal life high in the trees, but below the canopy. They are only rarely spotted near the ground.

The marmosets, also known as zaris or sagoin, are twenty-two New World monkey species of the genera Callithrix, Cebuella, Callibella, and Mico. All four genera are part of the biological family Callitrichidae. The term "marmoset" is also used in reference to Goeldi's marmoset, Callimico goeldii, which is closely related.