Adult male, showing the impressively long tail. Kampong Trail, Singapore.

Probably the most successful primate species in Southeast Asia (besides Homo sapiens), the Long-tailed Macaque is to be found in a wide range of habitats including primary and secondary forest, mangroves, plantations and the outskirts of towns and villages. Its success is largely due to a varied diet of fruits, leaves, small mammals and birds, shellfish and crabs, as well as human leftovers. 

It is identified by the length of its tail, by the shape of the muzzle, and its colour, which is generally grey-brown or reddish-brown. It has a noisy, aggressive temperament and travels in large troupes of up to 30.

The species ranges from Indochina, Southern Thailand and Peninsular Malaysia to Sumatra, Java, Borneo and the Philippines. In Singapore it is the commonest primate.