A rare and little-known primate of Southeast Asia, and was only recognized as a distinct species in 2013. For many years, it was thought to be a subspecies of the Phayre’s leaf monkey (Trachypithecus phayrei), but genetic studies revealed that it is in fact a separate species. Native to Laos, Vietnam, and parts of China and Myanmar, it inhabits subtropical and evergreen forests, often in rugged and mountainous terrain. Its fur is a soft silvery-gray to dark gray, with a pale belly and a black face framed by lighter whiskers, giving it a dignified, almost ghostly appearance.

Despite living in regions inhabited by people for centuries, it went unnoticed by science until very recently because of its resemblance to other gray leaf monkeys. This late recognition highlights how much biodiversity remains hidden in Southeast Asia, especially among primates that live in remote or difficult-to-access forests. Like other colobine monkeys, the Indochinese gray langur is primarily a leaf-eater, with a complex, multi-chambered stomach that allows it to digest fibrous leaves and unripe fruit. This adaptation enables it to thrive in habitats where fruit is scarce, though it also makes it highly dependent on intact forest ecosystems.

Socially, these langurs live in troops of a dozen or more individuals, usually with one adult male and several females with their young. They are arboreal and spend most of their lives in the forest canopy, where their long tails—often longer than their body—help them balance as they leap gracefully from tree to tree. Young langurs, like many in their genus, are born with bright orange fur, which gradually shifts to gray as they mature. This striking infant coloration is thought to help group members quickly recognize and protect the most vulnerable individuals.

Distribution

Country

Population est.

Status

Year

Comments

Cambodia

2015

China

2015

Yunnan

Laos

2015

Myanmar

2015

Thailand

2015

Vietnam

2015