Dendropithecus

Dendropithecus is an extinct genus of apes native to East Africa between 20 and 15 million years ago. It may have been the ancestor of modern gibbons, which it resembled in some respects.[2]

Dendropithecus was a slender ape, about 60 centimetres (2.0 ft) in body length. The structure of its arms suggest that it would have been able to brachiate, swinging between trees by its arms, but that it would not have been as efficient at this form of movement as modern gibbons. However, its teeth suggest a very gibbon-like diet, likely consisting of fruit, soft leaves and flowers.