Trachypithecus margarita (Elliot, 1909)

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cercopithecidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 550-755 : 744

148.

Annamese Langur

Trachypithecus margarita

French: Langur d’Elliot / German: Annam-Langur / Spanish: Langur annamita

Other common names: Annamese Silvered Langur, Elliot's Lutung

Taxonomy. Presbytis margarita Elliot, 1909 ,

Vietnam, Langbian.

Until recently, T. margarita was considered a synonym of T. germaini , but it was elevated to a full species based on genetic data. T. margarita is closely related to T. cristatus , T. auratus , T. mauritius , T. germaini , and T. selangorensis , and together they form the cristatus species group. Monotypic.

Distribution. Mainland South-east Asia in S Laos (N limit is 16° 23’ N), SC Vietnam (N limit is 14° 30’ N), and E Cambodia (Ratanakiri and Mondulkiri provinces); most likely the W limitis the Mekong River, but further studies are needed to confirm this. Records in Vietnam N to 16° 37° N are questionable.

Descriptive notes. There are no specific measurements available, but the Annamese Languris similar in size to Germain’s Langur (7. germaini ). Fur of the Annamese Langur is generally pale grayish, with underside and throat very light, contrasting with black forehead, forearms, hands, and feet. Face is gray, with white eye-rings in many individuals. Females have a whitish pubic patch.

Habitat. Lowland evergreen, semi-evergreen, mixed deciduous, riparian, and gallery forest. Records of the Annamese Langur in hilly areas or at higher elevations are few. It is sympatric with doucs ( Pygathrix ).

Food and Feeding. There is no specific information available for this species, but the Annamese Langur is probably primarily folivorous, as are other members of the cristatus species group.

Breeding. Infant Annamese Langurs have a golden-orange coat, with a white face, hands, and feet.

Activity patterns. There is no information available for this species.

Movements, Home range and Social organization. There is no specific information available for this species, but the Annamese Langur is most likely similar to other members of the cristatus species group.

Status and Conservation. CITES Appendix II. Classified as Endangered on The IUCN Red List (under 1. germaini ). The Annamese Langur is widespread but rare throughout its range. Densities are generally low. Only a few sightings have been recorded in the last few decades in Vietnam, and it might be the rarest and most threatened monkey in Laos. In Cambodia, it is widespread in certain areas (e.g. Mondulkiri Province), but rare in others. Throughout its distribution, major threats are habitat loss due to agricultural land use and hunting for food, traditional medicine, and the pet trade. It occurs in numerous protected areas, among them: Dong Phou Vieng, Xe Bang Nouan, Xe Pian, and Dong Hua Sao national biodiversity conservation areas and Bolaven Southwest Proposed National Protected Area in Laos; Cat Tien, Yok Don, Chu Mom Ray, Chu Prong, and Kon Ka Kinh national parks and Takou Nature Reserve in Vietnam; and Virachey National Park, Mondulkiri Protected Forest, and Lomphat, Phom Prich, Phom Nam Lyr, and Snoul wildlife sanctuaries in Cambodia. Population estimates for Annamese Langurs are not available. Additional surveys and taxonomic work are needed to elucidate its population status and distributional limits.

Bibliography. Duckworth et al. (1999), Groves (2001), Nadler, Momberg et al. (2003), Nadler, Timmins & Richardson (2008), Nadler, Walter & Roos (2005), Roos, Nadler & Walter (2008), Roos, Vu Ngoc Thanh et al. (2007), Timmins, Steinmetz et al. (2013).

Figures

140. Golden Langur (Trachypithecus gee), 141. Capped Langur (Trachypithecus pileatus), 142. Shortridge’s Langur (Trachypithecus shortridgei), 143. East Javan Langur (Trachypithecus auratus), 144. West Javan Langur (Trachypithecus mauritius), 145. Silvered Langur (Trachypithecus cristatus), 146. Selangor Silvery Langur (Trachypithecus selangorensis), 147. Germain’s Langur (Trachypithecus germaini), 148. Annamese Langur (Trachypithecus margarita)

Distribution. Mainland South-east Asia in S Laos (N limit is 16° 23’ N), SC Vietnam (N limit is 14° 30’ N), and E Cambodia (Ratanakiri and Mondulkiri provinces); most likely the W limitis the Mekong River, but further studies are needed to confirm this. Records in Vietnam N to 16° 37° N are questionable.