Olive colobus

The olive colobus, Procolobus verus, also known as the green colobus or Van Beneden's colobus, is the only species in the genus Procolobus, which once also held the red colobuses now placed in Piliocolobus. It is the smallest colobine monkey and is rarely seen because of its cryptic coloration and secretive nature. Its name refers to its dull olive upperparts, with hairs that run from greenish-yellow at the root to darker tips, and males average 4.6 kg and females 4.1 kg. It is found in the rain forests of West Africa from southern Sierra Leone to Nigeria, in second growth within tall forest, palm forest and swamps, and it can survive in small degraded forest fragments. It is mainly folivorous and prefers young leaves, lives in small groups and is almost always seen with other monkeys, particularly Diana monkeys. The IUCN classifies it as vulnerable, previously near threatened, because of habitat loss and hunting.