This arboreal monkey lives in forests of northern Sumatra. It has a mostly black body, a pale underside and a distinctive white V-shaped pattern around the eyes.
Most of its body is covered in black fur, while the underside and arms are white. White stripes from the crown meet in a V around the eyes.
Thomas’ langur is a monkey native to northern Sumatra, Indonesia. Researchers counted groups in 60 square kilometres of Sikundur forest and compared their density with forest conditions and distance from human settlements. Estimated density in the surveyed area ranged from 2.79 to 8.08 groups per square kilometre.
Group density rose with distance from habitation: for each kilometre farther away, the estimate increased by 0.38 groups per square kilometre. The study found no clear relationship with the measured forest structure. The results map how group density varied across one northern Sumatran forest.
An extinction-risk assessment has not been added yet.
In Sikundur forest, group density was higher farther from human settlements, rising by 0.38 groups per square kilometre for each kilometre of distance. The survey documented langur distribution in relation to settlement patterns in northern Sumatra.