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 genus Trachypithecus but was moved to the genus Semnopithecus based on DNA evidence indicating that is it more closely related to the gray langurs.
Trachypithecus is a genus of Old World monkeys containing species known as lutungs, langurs, or leaf monkeys. Their range is much of Southeast Asia.
The pig-tailed langur, monotypic in genus Simias, is a large Old World monkey, endemic to several small islands off the coast of Sumatra in Indonesia. Its face is black, its fur is black-brown and it has a relatively short tail. It is a diurnal species, feeding in the rainforest canopy on leaves, and to a lesser extent, fruit and berries. Little is known of its natural history, but it is heavily hunted, its populations have been declining rapidly and the International Union for Conservation of Nature has assessed its conservation status as being "critically endangered". It has been included on a list of the World's 25 Most Endangered Primates.
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 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. The golden langur 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.
Cát Bà Island is the largest of the 367 islands spanning 260 km2 that comprise the Cat Ba Archipelago, which makes up the southeastern edge of Lan Ha Bay in Northern Vietnam. Cat Ba island has a surface area of 285 km2 and maintains the dramatic and rugged features of Ha Long Bay.
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 monkey 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 silvery lutung, also known as the silvered leaf monkey or the silvery langur, is an Old World monkey. It is arboreal, living in coastal, mangrove, and riverine forests in Peninsular Malaysia, Sumatra, Borneo, Java, and other nearby islands.
The East Javan langur, also known as the ebony lutung, Javan langur or Javan lutung, is an Old World monkey from the Colobinae subfamily. It is most commonly glossy black with a brownish tinge to its legs, sides, and "sideburns". It is found on the island of Java, as well as on several of the surrounding Indonesian islands. The Latin word auratus in its scientific name means "golden", and refers to a less common color variant. Note that the common name golden langur is used for a different species.
Cúc Phương National Park is located in Ninh Bình Province, in Vietnam's Red River Delta. Cuc Phuong was Vietnam's first national park and is the country's largest nature reserve. The park is one of the most important sites for biodiversity in Vietnam.
The grey-shanked douc langur is a douc species native to the Vietnamese provinces of Quảng Nam, Quảng Ngãi, Bình Định, Kon Tum, and Gia Lai. The total population was estimated at 550 to 700 individuals in 2004. In 2016, Dr. Benjamin Rawson, Country Director of Fauna & Flora International's Vietnam Programme, announced a discovery of an additional population including more than 500 individuals found in Central Vietnam, bringing the total population up to approximately 1000 individuals.
Delacour's langur or Delacour's lutung is a critically endangered species of Old World monkey endemic to northern Vietnam. It is named for French-American ornithologist Jean Théodore Delacour.
François' langur, also known as Francois' leaf monkey, the Tonkin leaf monkey, or the white side-burned black langur is a species of Old World monkey and the type species of its species group. It is one of the least studied of the species belonging to the Colobinae subfamily.
The Laotian langur or white-browed black langur is a species of primate in the family Cercopithecidae. It is endemic to Laos. Its natural habitat is subtropical or tropical dry forests. Genetically the Indochinese black and Hatinh langurs are very close to the Laotian langur, and consequently it has been suggested they should be considered subspecies of it.
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.
Cát Bà National Park is a World Heritage Site designated as a biosphere reserve in northern Vietnam. The park is part of Cát Bà Island in Hạ Long Bay and is administered by the city of Haiphong. The park is located approximately 30 kilometres (19 mi) east of Hai Phong, covering about 263 square kilometres (102 sq mi) and comprising 173 square kilometres (67 sq mi) of land and 90 square kilometres (35 sq mi) of inshore water.
Germain's langur is an Old World monkey native to Thailand, Myanmar, Cambodia, Laos and Vietnam. The monkey was previously included in Trachypithecus cristatus and Trachypithecus villosus.
The Indochinese black langur is a poorly known Old World monkey native to Laos and adjacent Vietnam. It was originally described as a subspecies of T. auratus, but was later found to be a member of the T. francoisi group, with some maintaining it as a subspecies of that species. In 2001, it was recommended treating it as a separate species.
The World's 25 Most Endangered Primates is a list of highly endangered primate species selected and published by the International Union for Conservation of Nature (IUCN) Species Survival Commission (SSC) Primate Specialist Group (PSG), the International Primatological Society (IPS), Global Wildlife Conservation (GWC), and Bristol Zoological Society (BZS). The IUCN/SSC PSG worked with Conservation International (CI) to start the list in 2000, but in 2002, during the 19th Congress of the International Primatological Society, primatologists reviewed and debated the list, resulting in the 2002–2004 revision and the endorsement of the IPS. The publication was a joint project between the three conservation organizations until the 2012–2014 list when BZS was added as a publisher. The 2018–2020 list was the first time Conservation International was not among the publishers, replaced instead by GWC. The list has been revised every two years following the biannual Congress of the IPS. Starting with the 2004–2006 report, the title changed to "Primates in Peril: The World's 25 Most Endangered Primates". That same year, the list began to provide information about each species, including their conservation status and the threats they face in the wild. The species text is written in collaboration with experts from the field, with 60 people contributing to the 2006–2008 report and 85 people contributing to the 2008–2010 report. The 2004–2006 and 2006–2008 reports were published in the IUCN/SSC PSG journal Primate Conservation,, since then they have been published as independent publications.
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.
The white-headed langur is a Critically Endangered species of langur endemic to Guangxi, China.
