Thomas's langur

Thomas's langur, Presbytis thomasi, also known as the North Sumatran leaf monkey or Thomas's leaf monkey, is a primate of the family Cercopithecidae endemic to northern Sumatra, Indonesia, where it does not live south or east of Lake Toba and the Alas and Wampu rivers. It can be found in Gunung Leuser National Park, with substantial populations at Ketambe and Bukit Lawang. Its native names are reungkah in Acehnese and kedih in Alas. The hair on top of the head rises in a crown like a mohawk, white at the front with a dark grey stripe, with two tufts at the sides of the face; the belly is cream and the back grey. It is primarily folivorous but also eats fruit, flowers and occasionally toadstools and snails. It is preyed on by Sunda clouded leopards, Sumatran tigers, Asian golden cats and reticulated pythons. Deforestation threatens it, the IUCN rates it vulnerable, and its population has declined by thirty percent in the last few decades.