Never found west of the Mekong River. SIZE Head and body 48 to 67cm. Tail 82 to 89cm. The troop sleeps outside in mild weather and in caves for shelter in cold winters. Appears to be associated with outcrops of rocks.
Support needs to be given to the development and maintenance of reserves.
There were 55 individuals in 11 collections in 1992, most were presumed to be bred in captivity. There are six or seven subspecies within the francoisi group, all may be distinct species. Pate, D.E. 1991. Francois' Languar Studbook Presbytis francoisi francoisi North American Region . Metro Washington Park Zoo, Oregon.