Gray langurs, also called Hanuman langurs and Hanuman monkeys, are Old World monkeys native to the Indian subcontinent constituting the genus Semnopithecus. Traditionally only one species Semnopithecus entellus was recognized, but since about 2001, additional species have been recognized. The taxonomy has been in flux, but currently eight species are recognized.
The purple-faced langur, also known as the purple-faced leaf monkey, is a species of Old World monkey that is endemic to Sri Lanka. The animal is a long-tailed arboreal species, identified by a mostly brown appearance, dark face and a very shy nature. The species was once highly prevalent, found in suburban Colombo and the "wet zone" villages, but rapid urbanization has led to a significant decrease in the population level of the monkeys. It had traditionally been classified within the lutung genus Trachypithecus but was moved to the genus Semnopithecus based on DNA evidence indicating that is it more closely related to the gray langurs.
The Colobinae or leaf-eating monkeys are a subfamily of the Old World monkey family that includes 61 species in 11 genera, including the black-and-white colobus, the large-nosed proboscis monkey, and the gray langurs. Some classifications split the colobine monkeys into two tribes, while others split them into three groups. Both classifications put the three African genera Colobus, Piliocolobus, and Procolobus in one group; these genera are distinct in that they have stub thumbs. The various Asian genera are placed into another one or two groups. Analysis of mtDNA confirms the Asian species form two distinct groups, one of langurs and the other of the "odd-nosed" species, but are inconsistent as to the relationships of the gray langurs; some studies suggest that the gray langurs are not closely related to either of these groups, while others place them firmly within the langur group.
The lutungs, langurs, or leaf monkeys are a group of Old World monkeys in the genus Trachypithecus. Their range is much of Southeast Asia.
The surilis are a group of Old World monkeys in the genus Presbytis. They live in the Thai-Malay Peninsula, on Sumatra, Borneo, Java and smaller nearby islands. Besides surili, the common names for the monkeys in the genus also often use the terms "langur" or "leaf monkey."
Gee's golden langur, also known as simply the golden langur, is an Old World monkey found in a small region of Western Assam, India and in the neighboring foothills of the Black Mountains of Bhutan. Long considered sacred by many Himalayan people, the golden langur was first brought to the attention of the Western world by the naturalist Edward Pritchard Gee in the 1950s. Adult males have a cream to golden coat with darker flanks while the females and juveniles are lighter. It has a black face and a long tail up to 50 cm (19.69 in) in length. It lives in high trees and has a herbivorous diet of fruits, leaves, seeds, buds and flowers. The average group size is eight individuals, with a ratio of several females to each adult male. It is one of the most endangered primate species of India and Bhutan.
The Nilgiri langur is a langur. This primate has glossy black fur on its body and golden brown fur on its head. It is similar in size and long-tailed like the gray langurs. Females have a white patch of fur on the inner thigh. It typically lives in troops of nine to ten monkeys. Its diet consists of fruits, shoots and leaves. The species is classified as vulnerable due to habitat destruction and poaching for its fur and flesh, the latter believed to have aphrodisiac properties.
The toque macaque is a reddish-brown-coloured Old World monkey endemic to Sri Lanka, where it is known as the rilewa or rilawa, . Its name refers to the whorl of hair at the crown of the head, reminiscent of a brimless toque cap.
The black-footed gray langur is an Old World monkey, one of the species of langurs. Found in southern India, this, like other gray langurs, is a leaf-eating monkey.
The Hatinh langur is a highly threatened Old World monkey found in limestone forests in Vietnam, primarily in the Quảng Bình Province. A recent survey discovered a small population living in the Quảng Trị Province. Contrary to its name, it is not known from the Hà Tĩnh Province. The local Van Kieu minority refer to this lutung as the 'Con Cung', which roughly translates as "black, cliff-dwelling monkey with a long tail". It resembles the closely related François' langur, but its white cheek-stripes typically extend behind the ears onto the nape, and the overall black colour is non-glossy and has a brownish tinge.
The Cat Ba langur, also known as the golden-headed langur, is a critically endangered species of langur endemic to Cát Bà Island, Vietnam. It is among the rarest primates in the world, and possibly the rarest primate in Asia, with population size estimated at less than 70 individuals.
The northern plains gray langur, also known as the sacred langur, Bengal sacred langur and Hanuman langur, is a species of primate in the family Cercopithecidae.
The dusky leaf monkey, also known as the spectacled langur, or the spectacled leaf monkey is a species of primate in the family Cercopithecidae. It is found in Peninsular Malaysia, Myanmar and Thailand, and can occasionally be found in Singapore. During the day, these small, folivorous primates divide in sub-groups and forage for vegetation and fruit throughout the tropical forests. According to the IUCN, the dusky leaf monkey's population is declining due to habitat loss, poaching, and anthropogenic land use, which prompted the IUCN to classify the species as endangered in 2015.
Germain's langur is a lutung native to Thailand, Myanmar, Cambodia, Laos and Vietnam. The Old World monkey was previously included in Trachypithecus cristatus and Trachypithecus villosus.
Southern plains gray langur was the common name ascribed to Semnopithecus dussumieri by Mammal Species of the World in 2005. Along with several other Semnopithecus, it had been previously considered a subspecies of the northern plains gray langur, Semnopithecus entellus, i.e., Semnopithecus entellus dussumieri. Subsequent genetic research has revealed that Semnopithecus dussumieri is an invalid taxon. These monkeys live in groups in forests and other rural habitats, with some groups being habituated to human contact and feeding. They are herbivorous, feeding by day mainly on foliage, fruits and flowers, and sleeping at night high in a tree.
The Nepal gray langur is a gray langur endemic to the Himalayas in Nepal, far southwestern Tibet, northern India, northern Pakistan, Bhutan and possibly Afghanistan. It is found in forests at an elevation of 1,500 to 4,000 metres. Its easternmost limit in India is Buxa Tiger Reserve in northern West Bengal, at least up to the Rydak river.
The Kashmir gray langur is an Old World monkey, one of the langur species. It is a leaf-eating monkey.
The western purple-faced langur, also known as the north lowland wetzone purple-faced langur, is a subspecies of purple-faced langur endemic to Sri Lanka. It lives in the wet zone in western Sri Lanka around the former capital city of Colombo. This subspecies are known to live in tropical rainforest, specifically in an area of Sri Lanka, where it is noted to rain two times more compared to the neighboring region. The subspecies is generally gray-brown with lighter whiskers, a gray rump patch, and dark forearms and legs. These monkeys also have dark brown or black, hairless faces. Their hands and feet are also hairless. When infants, their fur is medium brown to light gray, however it changes to their darker adult colors at between 12 and 16 weeks old. Typical length is between 48 and 67 centimetres excluding tail, with a 59 to 85 centimetres tail. On average, males weigh 8.5 kilograms (19 lb) and females weigh 7.8 kilograms (17 lb). Their average life span is about 26 years if the monkey was held in captivity. Due to their leafy diet, the western purple-faced langur back teeth, include high crowns and pointed cusps to make eating through greenery simpler. They also developed a digestive system that would allow them to break down cellulose in the leaves they eat. Although, leaves are their primary source of food, they also eat fruits and flowers. Female langurs hold a pregnancy for 195-210 days, and after the birth the offsprings are taken closely cared for by the mother until they are about 12-20 weeks old.
Kaludiya Pokuna Archeological Forest Site, is a forest with archeological remains in Kandalama, in the Dry Zone of Sri Lanka. The site has been handed over to the Girls' High School, Kandy in accordance with the "Urumaya Thani Nokaramu" program organized by the Department of Archeology. For the first time in Sri Lanka, a school was given custody of an archeological site.
