Primate Watching
Infant is born bright orange, which then changes to adult black color
© Adam Hermans
Kien Luong Karst Area, Vietnam
Primatology
Taxonomy & Occurrence
Trachypithecus germaini is a monotypic species (no subspecies). They are found on mainland SE Asia in Cambodia (west of Mekong River), southern Lao PDR, southern Myanmar, southern Thailand, and southern tip of Vietnam.
IUCN Conservation Status
Endangered
During the 1950s–1990s, populations of Indochinese Silvered Langur were almost universally considered conspecific with the better-known and widespread Silvered Langur of Sundaic Southeast Asia (Malay Peninsula, Borneo, Sumatra and associated small islands) [1].
Recent morphological and molecular analyses suggest, however, that these Sundaic and non-Sundaic populations are not conspecific, although this view is not universal [2]. Additionally, some used Indochinese Silvered Langur for all non-Sundaic populations [3,4], while others separated them into two species [5,6,7,8,9]: Indochinese Silvered Langur to the west of the Mekong and Annamese Silvered Langur east (although this barrier is not yet confirmed) [9].
Seeing this Species
The three silvered langurs (Indochinese Silvered Langur, Annamese Silvered Langur, and Silvered Langur) can be a bit difficult to distinguish but all are fun to see. All three species often seem at ease with nearby human activity. This makes for a great watching. The langurs sit in clear view munching on leaves, make spectacular leaps across gaps, and gather in large groups. Looking around, you may see black faces popping out.
Kien Luong Karst Area, Kien Giang Province, Vietnam
Kien Luong is highly popular with Vietnamese tourists, and for good reason. The site, located in the far southwest almost on the Cambodian border, boasts a series of spectacular limestone spires, including a few emerging from the bordering Gulf of Thailand. Nestled within one of the limestone karsts are a series of Buddhas. These religious caves and corresponding pagodas may be just the reason why the limestone habitats have survived and langurs thus far been protected. This protection, from pious tourists, may also be what led to their habituation and thus the ease in viewing.
Probability of success: ◆ ◆ ◆ ◆ ◇
Overlapping species: Long-tailed Macaque (Macaca fascicularis fascicularis)
Other sites:
Phu Quoc Island, Kien Giang Province, Vietnam
This district is the largest island of Vietnam, boosting 99 hills from north to south. Flights into Phu Quoc from Ho Chi Minh City are an option.
Overlapping species:
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Long-tailed Macaque (Macaca fascicularis fascicularis)
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Bengal Slow Loris (Nycticebus bengalensis)
Local contacts: You can contact me here at Primate Watching!
© Adam Hermans
Kien Luong Karst Area, Vietnam
An older infant is indicated by an adult black fur coat, in contrast to a newborn which is bright in orange
© Adam Hermans
Kien Luong Karst Area, Vietnam
References
[1] Timmins R.J., Steinmetz R., Poulsen M.K., Evans T.D., Duckworth J.W. & Boonratana R., 2013. The Indochinese silvered leaf monkey Trachypithecus germaini (sensu lato) in Lao PDR. Primate Conservation 26: 75-87.
[2] Brandon-Jones D., Eudey A.A., Geissmann T., Groves C.P., Melnick D.J., Morales J.C., Shekelle M. & Stewart C.-B., 2004. Asian primate classification. International Journal of Primatology 25: 97-164.
[3] Groves C.P., 2001. Primate taxonomy. Smithsonian Institution Press, Washington, D.C.
[4] Groves C.P., 2005. Order Primates. In: Mammal species of the world, 3rd edition, Wilson D.E. & Reeder D.M. (eds.), Johns Hopkins University Press, Baltimore, M.D.: 111-184.
[5] Nadler T., Walter L. & Roos C., 2005. Molecular evolution, systematics and distribution of the taxa within the silvered langur species group (Trachypithecus [cristatus]) in Southeast Asia. Zoologische Garten 75: 238-247.
[6] Francis C.M., 2008. A field guide to the mammals of Southeast Asia. New Holland, London.
[7] Roos C., Nadler T. & Walter L., 2008. Mitochondrial phylogeny, taxonomy and biogeography of the silvered langur species group (Trachypithecus cristatus). Molecular Phylogenetics and Evolution 47: 629-636.
[8] Hoang Minh Duc, Covert H.H., Roos C. & Nadler T., 2012. A note on phenotypical and genetic differences of silvered langurs in Indochina (Trachypithecus germaini and T. margarita). Vietnamese Journal of Primatology 2 (issue 1): 47-54.
[9] Roos C., Boonratana R., Supriatna J., Fellowes J.R., Rylands A.B. & Mittermeier R.A., 2013. An updated taxonomy of primates in Vietnam, Laos, Cambodia, and China. Vietnamese Journal of Primatology 2 (issue 2): 13-26.
Page Last Updated: 3 July 2022