Cynomolgus Monkey Skull measures 3.9 inches. Cynomolgus Monkey Skull is museum quality polyurethane resin cast. Known as Crab Eating Macaque Monkey

Cynomolgus Monkey or Crab Eating Macaques are found in southeast Asia from Burma to the Philippines and southward through Indochina, Malaysia, and Indonesia. They are found as far east as the Timor Islands.

Cynomolgus Monkey or Crab Eating Macaques ecologically diverse. Some of the habitats in which they have been found are primary forests, disturbed and secondary forests, and riverine and coastal forests of nipa palm and mangrove.

Long-tailed macaques live most successfully in disturbed habitats and on the periphery of forests.

Cynomolgus monkeys (Macaca fascicularis), also known as the long-tailed or crab-eating macaque, are non-human primates commonly used in biomedical research.

There are 10 subspecies of these macaques and they are found predominantly in southeast Asia. The cynomolgus monkeys are typically 15-22 inches long, and the females weigh between 7-13 pounds, while males can weigh between 11-20 pounds.

Cynomolgus monkeys are frequently used in biomedical research because researchers believe these monkeys are the ideal models due to the 90-93% genetic similarity to and recent evolutionary divergence from humans.

They are used for basic research studies in disease pathology and treatment, vaccine development, immunology, and cardiology, amongst others.

Cynomolgus monkeys are also used for toxicology and efficacy studies for drug development in the pharmaceutical industry based on certain FDA Guidance for Industry.

However, the usefulness of performing in vivo experiments in these animals has been recently called into question.

Examples include the failure of HIV modeling due to lack of AIDS development in monkeys and inability to successfully translate HIV vaccine research into humans.

The effectiveness of using cynomolgus monkeys may come down to a case by case basis.

By performing ex vivo studies with cynomolgus monkey samples, such as peripheral mononuclear blood cells or whole blood, researchers may be able to glean some insight into whether in vivo studies would be beneficial.

In addition, regulatory agencies, including the FDA and EMA, suggest and may even require studies with non-human cells to assess cross-species reactivity.