They are red-brown with pale underparts; the young monkey has a blue face. The male's nose is long and pendulous, the female's is smaller, and the young's is upturned. Males are 22-28 in. (56-72 cm) long, have a 26-29-in. (66-75-cm) tail, and weigh 26-53 lbs (12-24 kg); females are smaller and much lighter
Species (Nasalis larvatus, family Cercopithecidae) of long-tailed arboreal Old World monkey of swampy mangrove forests on Borneo. Diurnal vegetarians, they live in groups of about