The white-headed langur (Trachypithecus poliocephalus) is a critically endangered langur from Cat Ba Island, Vietnam (T. p. poliocephalus), and Guangxi, China (T. p. leucocephalus). Both taxa are overall blackish, but the crown, cheeks and neck are yellowish in T. p. poliocephalus, while they, as suggested by its scientific name, are white in T. p. leucocephalus. As all members of the Trachypithecus francoisi species group, this social, diurnal lutung is found in limestone forests.
