Langur

Langur is a common name for various Old World monkeys in the subfamily Colobinae, primarily folivorous and arboreal. The group includes species in the genera Trachypithecus (Asian leaf monkeys) and Semnopithecus (old-world hanuman langurs), among others. Taxonomic placement varies by authority, with some authorities recognizing additional genera such as Presbytis within langurs. They are distributed from Afghanistan and the Indian subcontinent to Southeast Asia and southern China; several species are adapted to forest, montane, and urban habitats.

Langurs are medium-sized with long tails, slender limbs, and variable coloration that ranges from gray and brown to black. They possess sacculated stomachs to ferment leaves, allowing them to digest high-fiber foliage. Diet is largely folivorous but includes fruits, seeds, and young shoots. They are diurnal and mostly arboreal, though some species descend to ground level to forage or raid crops. Social organization varies from one-male, multi-female groups to multi-male groups and fission–fusion patterns; mating and infant-rearing are usually centralized around a breeding female and her core kin.

Conservation status is variable; habitat loss, fragmentation, hunting, and conflict with humans put many species at risk, while others remain common or increasing in protected areas. Langurs are culturally significant in some regions and feature in local folklore and religious practices; they are also used in ecological studies of folivory, social behavior, and conservation biology.