Rhinopithecus Milne-Edwards, 1872

Semnopithecus Milne-Edwards, 1870:341.

Type species Simia entellus Dufresne, 1797.

Rhinopithecus Milne-Edwards, 1872:233, pls [Plates] XXXVI, XXXVII.

Type species Semnopithecus roxellana Milne- Edwards, 1870, by original designation.

Pygathrix Groves, 1970:562.

Type species Simia nemaeus L., by original designation.

CONTEXT AND CONTENT. Order Primates, suborder Haplorrhini, infraorder Simiformes, superfamily Cercopithecoidea, family Cercopithecidae, subfamily Colobinae, tribe Rhinopithecini. In addition to Rhinopithecus, this tribe includes the genera Pygathrix, Simias, and Nasalis. Rhinopithecus has 5 species: Rhinopithecus bieti (black-and-white snub-nosed monkey), R.roxellana (golden snub-nosed monkey), R. avunculus (Tonkin snub-nosed monkey), R. brelichi (gray snub-nosed monkey), and R. strykeri (black or Burmese snub-nosed monkey).

The key is based on metrics in Groves (1970), Smith and Xie (2008), and Geissmann et al. (2010).

1. Tail> 135% of head–body length……………………………2

Tail <135% ofhead–bodylength ……………………………3

2. Body all black except for whitish mustache, chin hair, ear tufts, and perineal area.....….....….....…......…....... R. strykeri Black back, white face and underparts,…..…..…. R. avunculus

3. Body mostly dark gray, lighter underparts with a chestnut band across chest.............................. R. brelichi Body either rufous to golden yellow or mostly black and white......................................................................................4

4. Body rufous to golden yellow, blue face, hairs not elongated in ischial region........................................... R. roxellana Body with black, gray, and white pelage; long (200–210 mm) hairs in ischial region and upper thighs forming a fringe; whitish shoulders and thighs, white face except for pink lips.................................................................................... R. bieti.