The Grey-cheeked Mangabey (Lophocebus albigena) is an Old World monkey found in the forests of Central Africa. They range from Cameroon down to Gabon and across in western Uganda. The Grey-cheeked Mangabey is a dark monkey. It looks in shape overall like a small, hairy baboon. Its thick brown fur is almost black in its forest home. It has a slightly golden mane around the neck. The sexes are similar, with the males slightly larger than the females.
The Grey-cheeked Mangabey lives in a variety of habitats in the forests of Central Africa. It is generally thought to live in either swamp or primary forests. In some areas, it has also been found in secondary forest as well. It feeds primarily on fruit, particularly figs. It eats other fruits seasonally, as well as shoots, flowers and insects.
The Grey-cheeked Mangabey lives in groups of between 5 to 30 individuals. The groups have either a single male or (more usually) several, without a single dominant male. Young males leave the troop once they are adult and join other troops. The females stay in the troop of their birth. If troops become too large they may split. Confrontations between troops are rare. They usually avoid other troops. Their territories cover several square miles of forest, and can overlap with other troops and shift over time.