(Presbytis melalophos)
The presbyopic Sumatra (Sumatran Surili (Raffles,1821 )) is a primate of the family of cercopithecuses.The average weight is 5.8 to 5.9 kg,with males slightly larger than females.Like all presbyts,the body is slender,with long back legs and a long tail.The color depends on the subspecies.