Some haven't even been discovered yet. Here's one that's amazing. It's a group of medium-sized African monkeys.
Mangabeys range in color from fawn, or light brown, to black.
There are nine species. One, the sanje mangabey, was discovered as recently as 1989 in Tanzania's Uzungwa Mountains. There are mangabeys across Africa's central belt, from Sierra Leone to Nigeria, Zaire and Kenya. Mangabeys use their faces like people do - to show how they feel. They have a white pigment on their eyelids, between the brow and the upper lid.