The Javan surili (''Presbytis comata'') is a

vulnerable species A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, ...

Old World monkey Old World monkey is the common English name for a family of primates known taxonomically as the Cercopithecidae (). Twenty-four genera and 138 species are recognized, making it the largest primate family. Old World monkey genera include baboons ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the western half of

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

, a

biodiversity hotspot A biodiversity hotspot is a biogeographic region with significant levels of biodiversity that is threatened by human habitation. Norman Myers wrote about the concept in two articles in ''The Environmentalist'' in 1988 and 1990, after which the co ...

. Other common names by which it is known by include gray, grizzled or Sunda Island surili; grizzled or stripe-crested langur; Javan grizzled langur; grizzled, Java or Javan leaf monkey; langur gris. There are two subspecies of the Javan surili: * ''Presbytis comata comata'' - Occurs in western Java * ''Presbytis comata fredericae'' - Occurs in central Java This

colobine 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 ...

species has a sacculated stomach to assist the breakdown in the cellulose from the leaves it feeds on. It has a small, slender face and tail, and large round stomachs. Its coloring ranges from dark gray to white. Leaf monkeys tend to be active during the day, spending up to 5 hours grooming themselves.

Distribution

The Javan surili is found in the western half of

Java, Indonesia Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mos ...

. It ranges as far east as Mt. Lawu on the border with East Java. According to a recent study, this species is mostly confined to Sundaland due to changes in the geography, sea level and vegetation that occurred during the Pleistocene era, and partly due to the type of vegetation and soil there today. The Javan surili lives in primary and secondary lowland rainforests, with an altitudnal range of 2500 meters.

Ecology

The Javan surili mostly consumes leaves, however, it will also consume flowers, fruits, and seeds. This species appears to be more

folivorous In zoology, a folivore is a herbivore that specializes in eating leaves. Mature leaves contain a high proportion of hard-to-digest cellulose, less energy than other types of foods, and often toxic compounds.Jones, S., Martin, R., & Pilbeam, D. (1 ...

than any other member of the genus ''Presbytis'', with over 62% of its overall diet composed of young leaves and 6% of mature leaves.

Conservation

This species is currently listed on the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

red list of vulnerable species because of habitat loss due to human activity. It is estimated that fewer than 1,000 exist today in their natural habitat and only 4% of their natural habitat remains. Most of the loss of its original habitat is due to the clearing of the rainforests in Indonesia. Only 4% of its original habitat remains and the population has decreased by at least 50% in the last ten years. Of the two subspecies of ''P. comata'', the ''frediricae'' subspecies is among the rarest and most at risk for

extinction Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

, located in one of the most highly populated areas on the island and near an active volcano.

References

{{Taxonbar, from=Q285813

Javan surili The Javan surili (''Presbytis comata'') is a vulnerable species of Old World monkey endemic to the western half of Java, Indonesia, a biodiversity hotspot. Other common names by which it is known by include gray, grizzled or Sunda Island surili; ...

Endemic fauna of Indonesia Endemic fauna of Java Fauna of Java Primates of Indonesia Endangered fauna of Asia

Taxa named by Anselme Gaëtan Desmarest