Trachypithecus shortridgei (Wroughton, 1915)

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 : 742

142.

Shortridge’s Langur

Trachypithecus shortridgei

French: Langur de Shortridge / German: Shortridge-Langur / Spanish: Langur de Birmania

Other common names: Shortridge’s Capped Langur

Taxonomy. Presbytis shortridgei Wroughton, 1915 ,

Burma, Homalin, upper Chindwin.

T. shortridgei forms, together with T. pileatus and T. geei , the pileatus species group. The phylogenetic position of this group remains unresolved, and they might have evolved through hybridization of ancestors (3-4-7-1 million years ago) of today’s genera Trachypithecus and Semnopithecus . In the Chindwin headwaters, there might pe intergradation with 7. pileatus or an undescribed variation of 1. shortridgei . Monotypic.

Distribution. NE Myanmar, E of the Chindwin River (Kachin State N to Myitkyina District) and SW China (Dulong River Valley in Gongshan County, NW Yunnan Province).

Descriptive notes. Head—body 67-72 cm, tail 95-104 cm; no specific data are available for body weight. Shortridge’s Langur is strikingly uniform in color, being silvery-gray on head and body (including underside, crown, and cheek whiskers), with lighter legs. Tail becomes increasingly dark toward tip. Hands and feet are black. Backward-swept cheek whiskers are shorter than those of Capped Langurs (71. pileatus ) and Golden Langurs (71. geet), and they contrast with short, upright crown hair. External scrotum is absent.

Habitat. Lowland evergreen and semi-evergreen forest at elevations of 200-2500 m. Shortridge’s Languris rarely encountered at higher elevations. It is sympatric with the Stryker’s Snub-nosed Monkey ( Rhinopithecus strykerr).

Food and Feeding. There is no information available for this species.

Breeding. There is no information available for this species.

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

Movements, Home range and Social organization. There is no information available for this species.

Status and Conservation. CITES Appendix I. Classified as Endangered on The [UCN Red List. Shortridge’s Languris protected in Myanmar and China and occurs in at least three protected areas: Hponkanrazi Wildlife Sanctuary and Hkakaborazi National Park in Myanmar and Gaoligongshan National Nature Reserve in China. Langurs occur also in Hukaung Tiger Reserve, but the species is not known. Population numbers of Shortridge’s Langur are unknown, but they are believed to be declining because of habitat loss and hunting. They are hunted for meat and use in traditional medicine, and they are sometimes exported illegally to China. Habitat loss from agriculture, logging, and firewood extraction and the planned Tazone hydroelectric power dam at the Chindwin River are major threats. The latter will result in direct loss of a large part of the remaining habitat used by Shortridge’s Langur and will harm populations via an increase of hunting by dam construction workers. If Shortridge’s Langur does not occur in Hukaung Tiger Reserve, which provides a large area of suitable lowland habitat, it is seriously threatened because most other protected areas in Myanmar are highland habitats, and suitable habitat below 900 m is heavily degraded and fragmented. There is an urgent need for further survey work to determine current population status, limits of distribution, and habitat preferences of this poorly known species.

Bibliography. Htun et al. (2008), Groves (2001), Karanth (2008, 2010), Pocock (1939).

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. NE Myanmar, E of the Chindwin River (Kachin State N to Myitkyina District) and SW China (Dulong River Valley in Gongshan County, NW Yunnan Province).