Callithrix

Callithrix 

a genus of monkeys of the family Callithricadae. The body length measures 15–30 cm, the tail length 18–40 cm, and the weight 230–450 g. The coloring varies: completely black (black-penciled marmoset, C. penicillata), yellow (yellow-legged marmoset, C. chrysoleuca), black body with white head (Geoffrey’s marmoset, C. geoffroyi), or light body with dark tail (C. argentata). The hair is thick and rather long; there are usually tufts on the ears. There are eight species, distributed in South America (Brazil and Bolivia). The Callithrix inhabit trees and are very agile and quick. Living in groups of three to 12, they are active during the day. They feed on the leaves and fruit of trees, on insects, and on small birds and their eggs. After a gestation period of 140–150 days, the female gives birth to one to three young. The male often helps in rearing the young.