The body length of Colobinae. Adult pig-tailed langurs have black faces and small snub-noses. The coat of the dark phase of is blackish-brown with light speckled hair on the nape, shoulder, and upper back. The tail of this species is not only short, but also hairless, except for a small amount of hair at the tail tip. (Ankel-Simons, 2000; Burton, 1995; Noë and Bshary, 2001)ranges from 490 to 550 mm in males and from 460 to 550 mm in females. The average weight is around 8.7 kg for males and 7.1 kg for females. The tail length of varies between 14 and 15 cm. Two color varieties exist for , a dark grey phase and a creamy buff phase, with the dark grey phase being more common. The creamy buff phase is found in roughly one in four individuals. The limbs are of equal length and the tail is rather short compared to other primate species in the subfamily
Few data exist regarding the reproductive cycle of (Burton, 1995), but it is believed that a single birth occurs sometime during June and July. This species also exhibits sexual swelling, a trait that is rare in other Asian colobines.
Little is known about the parental investment of Nasalis larvatus. Female N. larvatus carry, nurse, and stay close to their young for about a year. While the males do not provide as much care as the females, they do protect their young from males from other groups. (Woltanski, 2004), but there is information about their close relatives, proboscis monkeys,
No information is available regarding the lifespan and longevity of N. larvatus lives at least 23 years in captivity. (Woltanski, 2004), but its relative
This species eats leaves, fruits, and berries. Feeding occurs after sunrise near the trees used for sleeping and again in the afternoon. Adult males lead the foraging and the females and young follow behind . (Burton, 1995; Tilson, 1977)
There is little available information on the ecosystem role of the pig-tailed langur. They may aid in seed dispersal of tropical fruiting trees.
Pig-tailed langur meat is considered a delicacy. These are important members of the ecosystems in which they live, they could contribute to the development of the ecotourism industry in the Mentawai islands. (Burton, 1995)
There are no known adverse affects ofon humans.
Pig-tailed langurs are listed as an endangered species under the IUCN. The population consists of fewer than 10,000 individuals. Habitat loss due to logging is the main cause of population decline. Hunting is also a major problem, especially in the Pagai Islands because (Burton, 1995; Eudey and Members of the Primate Specialist Group 2000, 2004; Nowak, 1999)meat is considered a delicacy. This species receives protection at the Teiteibatti Wildlife Reserve, located on the only island that provides such security. It is believed that the population size of has decreased by 50% during the last decade and will most likely continue to drop another 50% during the next decade.
This species was previously recognized under the name Nasalis concolor.
Tanya Dewey (editor), Animal Diversity Web.
Lyndsay Rankin (author), Michigan State University, Barbara Lundrigan (editor, instructor), Michigan State University.
uses sound to communicate
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
an animal that mainly eats leaves.
A substance that provides both nutrients and energy to a living thing.
an animal that mainly eats fruit
An animal that eats mainly plants or parts of plants.
animals that live only on an island or set of islands.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
found in the oriental region of the world. In other words, India and southeast Asia.
having more than one female as a mate at one time
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
uses touch to communicate
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
Ankel-Simons, F. 2000. Primate Anatomy: An Intrduction. San Diego, California: Academic Press.
Burton, F. 1995. The Multimedia Guide to the Non-human Primates. Scarborough, Ontario: Prentice Hall Canada.
Eudey, A., Members of the Primate Specialist Group 2000. 2004. "IUCN Red List of Threatened Species: Simias concolor" (On-line). Accessed March 16, 2006 at http://www.iucnredlist.org/search/details.php?species=20229.
Nowak, R. 1999. Pig-tailed Langur. Pp. 596-597 in Walker's Mammals of the World, Vol. 1, 6th Edition. Baltimore: The Johns Hopkins University Press.
Noë, R., R. Bshary. 2001. Colobus and Leaf Monkeys. Pp. 380-395 in D Macdonald, ed. The Encyclopedia of Mammals, Vol. 2, Revised Edition. New York: Facts on File.
Tilson, R. 1977. Social organization of simakobu monkeys (Nasalis concolor) in Siberut Island, Indonesia. Journal of Mammalogy, 58(2): 202-212.
Vogel, C., P. Winkler. 1990. Langurs and Colobi. Pp. 296-324 in S Parker, ed. Grzimek's Encyclopedia of Mammals, Vol. 2, 1 Edition. New York: McGraw-Hill Publishing Company.
Whitten, A., J. Whitten. 1982. Preliminary observations of the Mentawai macaque on Siberut Island, Indonesia. International Journal of Primatology, 3(4): 445-459.
Woltanski, A. 2004. "Nasalis larvatus" (On-line). Animal Diversity Web. Accessed April 18, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Nasalis_larvatus.html.