Crab-eating macaque

Crab-eating macaque
In Singapore, 2025
CITES Appendix II
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Family: Cercopithecidae
Genus: Macaca
Species:
M. fascicularis
Binomial name
Macaca fascicularis
Raffles, 1821
      native range
Synonyms
  • Simia cynomolgus Schreber, 1775
  • Simia aygula Linnaeus, 1758
  • Macacus carbonarius Cuvier, 1825
  • Macaca irus Geoffroy,1826
  • Semnpithecus kra Lesson, 1830

The crab-eating macaque (Macaca fascicularis), also known as the long-tailed macaque or cynomolgus macaque, is a cercopithecine primate native to Southeast Asia. As a synanthropic species, the crab-eating macaque thrives near human settlements and in secondary forests. The crab-eating macaque has developed attributes and roles assigned to them by humans, ranging from cultural perceptions as being smart and adaptive, to being sacred animals, being regarded as vermin and pests, and becoming resources in modern biomedical research. It has been described as a species on the edge, living on the edge of forests, rivers, and seas, at the edge of human settlements, and perhaps on the edge of rapid extinction.

The crab-eating macaque is omnivorous and frugivorous. It lives in matrilineal groups ranging from 10 to 85 individuals, with groups exhibiting female philopatry and males emigrating from natal group at puberty. The crab-eating macaque is the only old-world monkey known to use stone tools in their daily foraging, and it engages in a robbing and bartering behavior in some tourist locations.

The crab-eating macaque is the most traded primate species and also the most popular species used in scientific research. Due to these threats, the crab-eating macaque was listed as Endangered on the IUCN Red List in 2022.