Tonkin Leaf Monkey

Common name for a species of lutung with the scientific name Trachypithecus francoisi, and also commonly known as François' or Francois' Leaf Monkey and François' or Francois' Langur, named after Auguste François (1857-1935), the French Consul at Longzhou County in southern China and the first person to bring this monkey to the attention of Western scientists, as well as White Side-burned Black Langur. It is a monotypic species, i.e. not a subspecies, and is considered endangered. It is mostly blackish with a brownish tinge and with white stripes on the cheeks, from mouth to ears. The Tonkin Leaf Monkey is very similar to the Hatinh Langur (fig.), but in the latter the white cheeks extends behind the ears to the back of the head, whereas it does not in the Tonkin Leaf Monkey. It is also very similar to the Laotian Langur (Trachypithecus laotum), which is endemic to Laos, and besides a clear genetic difference between the two, the white cheeks may also extend to behind the ears, though some may have largely white heads, with or without a dark crest, whereas yet others have nearly unmarked, black heads. The Tonkin Leaf Monkey is found only in the region of Southwestern China and northeastern Vietnam, where it dwells in mountainous limestone forests. 回