Trachypithecus phayrei (Blyth, 1847)

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 : 747-748

151.

Phayre’s Langur

Trachypithecus phayrei

French: Langur de Phayre / German: Phayre-Brillenlangur / Spanish: Langur de Phayre

Other common names: Phayre’s Leaf Monkey, Phayre's Leaf-monkey; Shan States Langur (shanicus)

Taxonomy. Presbytis phayrei Blyth, 1847 ,

Burma, Arakan.

1. playrei is a member of the obscurus species group, which also includes 7. obscurus , 1: crepusculus , and 1. barbei . Two subspecies recognized.

Subspecies and Distribution.

1. p. phayrei Blyth, 1847 — E Bangladesh, NE India (Assam, Mizoram, and Tripura states), and W Myanmar (SE through Arakan to Pegu).

I. p. shanicus Wroughton, 1917 — SW China (Yingjiang-Namting River and Tunchong-Homushu Pass districts in W Yunnan Province), and N & E Myanmar (Shan States and neighboring dry zone of N Myanmar).

Descriptive notes. Head-body 42-60 cm (males) and 44-57 cm (females), tail 75— 86 cm (males) and 72-80 cm (females); weight 5:7.9-1 kg (males) and 6.4-7.5 kg (females). Phayre’s Langur is very similar to the Dusky Langur (7. obscurus ) in overall appearance, butits legs,tail, and crown cap are not so contrastingly pale colored. Face is dark gray, except for white ocular rings and a depigmented area on mouth and nasal septum. The nominate subspecies (1. p. phayrei ) is dark brown, buffy or gray-brown above, with sharply contrasting gray or whitish underparts. Its face is black, except for a fleshy-white muzzle and a white ring encircling each eye. There is no whorl behind its eyebrows. The “Shan States Langur” (1. p. shanicus) is generally fawn colored, with a trace of lightening on nape and hands. Its feet are slightly darker than the rest of its body. There is either a single tall whorl or a parting behind its brows, but no crest on its crown. The depigmented area around its mouth is very wide, and white aroundits eyes is restricted to innersides.

Habitat. Primary and secondary high-elevation evergreen, semi-evergreen, and mixed moist deciduous forests throughout most of its range. In some areas,it also occurs in sparse woodlands and bamboo forests. Phayre’s Langur prefers dense cover and bamboo thickets along hillsides and streams. It can also be found in tea plantations.

Food and Feeding. Phayre’s Langur feeds mainly on leaves, flowers, seeds, sap, gum, figs, and bamboo shoots. In Bangladesh, mature leaves and young shoots form a major part of the diet (66%), followed by flowers and buds (16%) and fruits and seeds (14%). Seasons influence dietary choice, with leaves dominating the diet in December (76%) and the lowest preference for foliage (49%) in April. Fruits and seeds are preferred mostly in June (57%) when leaf consumption is low (15%). Consumption of flower and buds peaks in April (41%) and is lowest in January (9%). Bamboo shoots form a significant proportion ofits diet.

Breeding. Natal coat of Phayre’s Languris straw-colored. The gestation period of the nominate subspecies is 205 days, and the reproductive cycle is 28 days. Females are receptive throughout the ovarian cycle and during gestation. The average mating interval is 17 days. Female Phayre’s Langurs mate with subadult males during non-ovulatory periods and with alpha males during the periovulatory period. This reproductive strategy may confuse males regarding paternity and reduce the risk of infanticide from male aggression. Females mate in exchange for male security.

Activity patterns. Early mornings and late afternoons are peak foraging times for of Phayre’s Langurs in Bangladesh. They prefer to rest in certain trees such as the breadfruit tree ( Artocarpus chaplasha, Moraceae ) and Gmelina arborea (LLamiaceae) that provide good shade, and trees or bamboos such as Actinidia chinensis (Actinidiaceae) , Melocanna baccifera, M. bambusoides and Bambusa tulda ( Poaceae ) or Acacia mangium ( Fabaceae ) that offer moderate shade.

Movements, Home range and Social organization. In Bangladesh, Phayre’s Langurs split into subgroups while foraging but communicate and maintain contact visually and with vocalizations. Group size has a significant effect on infant development. Infants develop more slowly in the larger groups. This phenomenon is attributed to intragroup competition for resources that exert a negative effect on individual energy and time budgets.

Status and Conservation. CITES Appendix II. Classified as Endangered on The IUCN Red List, including both subspecies. Both subspecies have undergone declines of more than 50% over the last three generations because of habitat loss and hunting. Phayre’s Langur is protected under Schedule I, Part I of the Indian Wildlife (Protection) Act, 1972; Schedule III of the Bangladesh Wild Life (Preservation) Order, 1973; and Category I of the Chinese Wildlife Protection Act. In Myanmar,it has been protected since 1994. Phayre’s Langur is commonly hunted for its gallstones, which are used in traditional medicine. In 2008, the total number of the Shan States Langur was estimated at fewer than 2500 individuals. Phayre’s Langur occurs in at least eleven protected areas: the nominate subspecies in Lawachara National Park and Rama-Kalenga Wildlife Sanctuary in Bangladesh and Dampa, Gumti, Sepahijala, and Trishna wildlife sanctuaries in India, and the Shan States Langur in Gaoligongshan, Daxueshan, and Tongbiguan national nature reserves in China and Pidaung Wildlife Sanctuary and Popa Mountain National Park in Myanmar. In India and Bangladesh, populations are small and severely fragmented and are affected by changes in land use such as conversion of forests to tea and timber plantations, logging for paper mills and charcoal production, livestock ranching, shifting agriculture and human settlement, and habitat degradation through harvesting of non-timber forest produce. In Bangladesh, Phayre’s Langur has declined by more than 80% in the last 20 years because of tourism, plantations, exotic species replacing indigenous varieties, encroachments, and the construction of roads and railway tracks. In China, populations of Phayre’s Langur in Gaoligongshan Nature Reserve and Tongbiguan Nature Reserve are healthy. There is no information on its status in Myanmar.

Bibliography. Aziz & Feeroz (2009), Bhattacharya & Charaborty (1990), Bleisch, Brockelman et al. (2008), Choudhury (1987, 1994a, 1994b), Groves (2001), Gupta (1997, 1998, 2000), Gupta & Kumar (1994), Lu et al. (2010), Molur et al. (2003), Pages et al. (2005), Pan Ruliang et al. (1993), Timmins, Duckworth et al. (2013).

Figures

149. Tenasserim Langur (Trachypithecus barber), 150. Dusky Langur (Trachypithecus obscurus), 151. Phayre’s Langur (Trachypithecus phayrei), 152. Indochinese Gray Langur (Trachypithecus crepusculus), 153. Cat Ba Langur (Trachypithecus poliocephalus), 154. White-headed Langur (Trachypithecus leucocephalus), 155. Delacour’s Langur (Trachypithecus delacouri), 156. Francois’s Langur (Trachypithecus francoisi), 157. Black Langur (Trachypithecus ebenus), 158. Laos Langur (Trachypithecus laotum), 159. Hatunh Langur (Trachypithecus hatinhensis)

Subspecies and Distribution. 1. p. phayrei Blyth, 1847 — E Bangladesh, NE India (Assam, Mizoram, and Tripura states), and W Myanmar (SE through Arakan to Pegu). I. p. shanicus Wroughton, 1917 — SW China (Yingjiang-Namting River and Tunchong-Homushu Pass districts in W Yunnan Province), and N & E Myanmar (Shan States and neighboring dry zone of N Myanmar).