Definition
'Callithrix' is a genus of New World monkeys within the family Callithricidae, encompassing several species of marmosets. These small primates are characterized by their claw-like nails and often have distinctive tufts of fur around their ears. They inhabit the rainforests of South America, living in small family groups. They feed on insects, fruits, and tree sap. 'Callithrix' helps to group and differentiate closely related species.