Marmosets
Common marmoset (Callithrix jacchus) at Tibau do Sul, Rio Grande do Norte
Scientific classification
Included groups
Callibella M.G.M. van Roosmalen & T. van Roosmalen, 2003 (Roosmalens' dwarf marmoset) Callimico Miranda-Ribeiro, 1922 (Goeldi's marmoset) Callithrix Erxleben, 1777 (Atlantic marmosets) Cebuella Gray, 1866 (pygmy marmosets) Mico Lesson, 1840 (Amazonian marmosets)
Cladistically included but traditionally excluded groups
Leontopithecus Lesson, 1840 (lion tamarins) Saguinus Hoffmannsegg, 1807 (tamarins)

The marmosets are a group of New World monkeys.There are 22 marmoset species in four genera. All are in the biological family Callitrichidae. The term marmoset is also used in reference to the Goeldi's marmoset, Callimico goeldii, which is closely related.