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Trachypithecus laotum | Laotian Langur


Good spot: Phou Hin Boun National Biodiversity Conservation Area, Khammouane Province, Lao PDR




Taxonomy & Occurrence

Trachypithecus laotum is a monotypic species (no subspecies). It is found in the Khammouane and Borikhamxai Provinces in Lao PDR. 


IUCN Conservation Status



Its taxonomic status relative to Hatinh Langur requires clarification, although there is a clear genetic difference between the two [1].


Seeing this Species

They have been observed in the northern part of Phou Hin Boun National Biodiversity Conservation Area (NBCA), Khammouane Province, Lao PDR [2]. Even better, Steinmetz et al. (2011) offer a map and a table of 15 years of sightings, including GPS coordinates, time of day, and the reaction of the langurs [3]. The map is included below. The table is too large to include but it is an incredible resource.



































Probability of success:  ?


Overlapping species


Other sites:


Local contacts




[1] Roos C., 2004. Molecular evolution and systematics of Vietnamese primates. In: Nadler T., Streicher U. and Ha Thang Long (eds), Conservation of primates in Vietnam, Frankfurt Zoological Society, Vietnam Primate Conservation Programme, Endangered Primate Rescue Center, Cuc Phuong National Park, Hanoi, Hanoi, Vietnam.

[2] Nadler T., 2009. Observations of Lao langurs (Trachypithecus [laotum] laotum) and black langurs (Trachypithecus [laotum] hatinhensis morph ebenus) in Khammouane Province, Laos and remarks to their systematic position. Vietnamese Journal of Primatology 1 (issue 3): 9-15.

[3] Steinmetz R., Timmins R.J. &, Duckworth J.W., 2011. Distribution and conservation status of the Lao leaf monkey (Trachypithecus (francoisi) laotum). International Journal of Primatology 32: 587-604.


Illustration by Stephen Nash




Page Last Updated: 3 July 2022

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