Cynomolgus Macaque

Macaca fascicularis

The cynomolgus macaque, Macaca fascicularis, is also called the long-tailed macaque or crab-eating macaque. It ranges across much of Southeast Asia, using mangroves, forests, river edges, farms, and cities. The species has a slim body, long tail, cheek pouches, expressive social behavior, and flexible omnivorous feeding habits. Troops are matrilineal, with females remaining in their birth groups while males commonly disperse.

This macaque is not a suitable pet and is managed under strict regulation because of its intelligence, strength, social needs, and zoonotic disease concerns. It is one of the most widely used nonhuman primates in biomedical research, where breeding colonies require social housing, enrichment, veterinary oversight, and careful welfare review. Sanctuaries may receive retired, confiscated, or displaced animals, but placement is difficult and expensive. Wild populations face pressure from habitat loss, conflict, and capture for trade in some regions.