like the other tamarins and marmosets, geoffroy's tamarin is a new world monkey classified within the family callitrichidae. in 2001, colin groves included the callitrichids in the family cebidae, which also includes capuchin monkeys and squirrel monkeys, but in 2009 anthony rylands and russell mittermeier reverted to older classifications which considered callitrichidae a separate family. it is a member the genus "saguinus", the genus containing most tamarins. there are no recognized subspecies. in 1977, philip hershkovitz classified geoffroy's tamarin as a subspecies of the cotton-top tamarin ("saguinus oedipus"), which resides exclusively in colombia, based on fur coloration, cranial and mandibular morphology, and ear size. however, more recent research indicates that the two taxa differ sufficiently to be considered separate species.