Germain's langur (Trachypithecus germaini)[1] is an Old World monkey native to Thailand, Myanmar, Cambodia, Laos and Vietnam.[3][2] The monkey was previously included in Trachypithecus cristatus[3] and Trachypithecus villosus.[2]
| Germain's langur[1] | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Primates |
| Suborder: | Haplorhini |
| Infraorder: | Simiiformes |
| Family: | Cercopithecidae |
| Genus: | Trachypithecus |
| Species group: | Trachypithecus cristatus group |
| Species: | T. germaini
|
| Binomial name | |
| Trachypithecus germaini (A. Milne-Edwards, 1876)
| |
| |
| Joint range of Germain's langur and Annamese langur | |
Two subspecies were recognized:[3]
- Trachypithecus germaini germaini
- Trachypithecus germaini caudalis
Taxonomy and evolution
editGermain's langur is part of the leaf monkey subfamily Colobinae.[4] Two subspecies of the Germain's langur are recognized: Trachypithecus germaini germaini and Trachypithecus germaini caudalis.[4][5][6] However, the classification of the Germain's langur has been contested, with T. germaini being grouped with other species in its subfamily.[4][7] T. germaini and T. margarita were considered to be a single species, T. villosus, but morphological and genetic evidence has shown that they are distinct.[4][7][8][9] T. germaini has also been grouped with T. cristatus until recent reclassifications.[4]
Trachypithecus germaini goes by several common names such as the Indochinese lutung, Germain's langur, Germain's silver langur, Indochinese leaf monkey, and Indochinese silvered langur.[10]
Description
editGermain's langur has black colouration on its hands and feet, as well as the upper part of its body which fades into paler grey on its underparts.[4] They have long grey tails and white hairs on its round face.[4] Their young have bright orange fur.[4]
Distribution and habitat
editThe limits of the distribution of Germain's langur are not well known, but they are currently found in Asia, specifically Cambodia, Vietnam, Lao PDR, Myanmar, and Thailand.[2] Populations in Vietnam are severely reduced, with few sightings in the last 50 years.[2][11] In Lao PDR, the species has no continuous range, rather multiple patches of higher relative abundance.[2][11] Its distribution in Cambodia is widespread, but its abundance will vary from common to rare.[2] One of the few sites with a population estimate is Keo Seima Wildlife Sanctuary where a stable population of 1487 is reported.[12][13] In Thailand, the species is common, with many protected areas supporting large populations.[2] Germain's langur is a terrestrial arboreal species, often found in lowlands.[2] They prefer evergreen and semi-evergreen, riverine, mixed deciduous, and gallery forests.[2] They are not commonly found at high elevations or hilly areas.[2]
Behaviour
editThe diet of Germain's langur is folivorous consisting of leaves, shoots, and fruits.[4][14] They are also observed to consume mushrooms (mycophagy) and soil (geophagy).[14] Their folivorous diet dictates a resting period, in which they can undergo the process of rumination.[14][15]
Trachypithecus germaini, and other Asian colobines, are generally less frequently engaged in social interaction than frugivorous primates such as macaques.[14][16] They have a lower affinity to social behaviour in comparison to feeding and resting which makes up the majority of their day.[14] However, T. germaini is often found in troops of 10 to 50 individuals in close social proximity.[4][14]
Predators and threats
editPredators of Trachypithecus, including the Germain's langur, include leopards, tigers, dholes, and large snakes.[17] A variety of small carnivores will feed on the young.[17]
Prevalent threats to Germain's langur include hunting, exotic pet trading, and habitat loss due to agricultural expansion.[2]
Status and conservation
editT. germaini is considered endangered by the IUCN, with a greater than 50% decline in the past three generations.[2] It is listed under CITES Appendix II, meaning that trade of the species must be controlled to avoid endangerment.[2][18]
Little conservation efforts have been made, despite the species designation.[7][14] Several protected areas have been established across its range which aids in the conservation of the species. The species has been recorded in numerous protected areas in Vietnam and Thailand.[2] In Vietnam, their populations have increased in two protected areas, Phú Quốc National Park and Kiên Lương Karst Area, demonstrating the importance of conservation efforts.[19]
References
edit- ^ a b Roos, C.; Boonratana, R.; Supriatna, J.; Fellowes, J.R.; Groves, C.P.; Nash, S.D.; Rylands, A.B.; Mittermeier, R.A. (2014). "An updated taxonomy and conservation status review of Asian primates" (PDF). Asian Primates Journal. 4 (1): 2–38. Retrieved 2018-08-30.
- ^ a b c d e f g h i j k l m n o Duc, H.; Covert, H.; Ang, A.; Moody, J. (2021). "Trachypithecus germaini". IUCN Red List of Threatened Species. 2021: e.T39874A195374767. doi:10.2305/IUCN.UK.2021-1.RLTS.T39874A195374767.en. Retrieved 19 November 2021.
- ^ a b c Groves, C. P. (2005). Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press. p. 176. ISBN 0-801-88221-4. OCLC 62265494.
- ^ a b c d e f g h i j Supanuam, Praween; Tanomtong, Alongklod; Khunsook, Sumpars; Khrueanet, Wilailuk; Pinthong, Krit; Wonkaonoi, Weeranuch (2015). "The First Report on Standardized Karyotype and Idiogram of Indochinese Silvered Langur, Trachypithecus germaini germaini (Primates, Colobinae) in Thailand". Cytologia. 80 (2): 183–192. doi:10.1508/cytologia.80.183. ISSN 0011-4545.
- ^ Parr, John W. K. (2003). A Guide to the Large Mammals of Thailand. Bangkok: Sarakadee Press. ISBN 974-484-040-4.
- ^ Francis, Charles M. (2001). A photographic guide to mammals of Thailand & South-East Asia. Asia Books. OCLC 45914721.
- ^ a b c 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 (1): 75–87. doi:10.1896/052.026.0112. ISSN 0898-6207. S2CID 86278590.
- ^ Roos, C.; et al. (2008). "Mitochondrial phylogeny, taxonomy and biogeography of the silvered langur species group (Trachypithecus cristatus)". Molecular Phylogenetics and Evolution. 47 (2): 629–636. Bibcode:2008MolPE..47..629R. doi:10.1016/j.ympev.2008.03.006. PMID 18406631.[dead link]
- ^ Nadler, Tilo (2016). Rowe, Noel; Myers, Marc (eds.). All the World's Primates. Pogonias Press. pp. 601–602. ISBN 978-1-940496-06-1.
- ^ "Checklist of CITES species". checklist.cites.org. Retrieved 2020-04-07.
- ^ a b Duckworth, William; Salter, Richard Edward; Khamkhoun Khounboline, eds. (1999). Wildlife in Lao PDR: 1999 status report. World Conservation Union. ISBN 2-8317-0483-9. OCLC 799695132.
- ^ Nuttall, Matthew N.; Griffin, Olly; Fewster, Rachel M.; McGowan, Philip J. K.; Abernethy, Katharine; O'Kelly, Hannah; Nut, Menghor; Sot, Vandoeun; Bunnefeld, Nils (2022). "Long-term monitoring of wildlife populations for protected area management in Southeast Asia". Conservation Science and Practice. 4 (2): e614. Bibcode:2022ConSP...4E.614N. doi:10.1111/csp2.614. hdl:1893/33780. ISSN 2578-4854. S2CID 245405123.
- ^ Griffin, O.; Nuttall, M. (2020-12-04). Status of Key Species in Keo Seima Wildlife Sanctuary 2010-2020. Wildlife Conservation Society (Report). doi:10.19121/2020.Report.38511. S2CID 229677607.
- ^ a b c d e f g de Groot, Brenda; Nekaris, Anna (2016). "Ecology of the Germain's Langur Trachypithecus germaini in a Pre-release Environment and the Implications for its conservation" (PDF). Asian Primates Journal. 6 (1). Retrieved 30 December 2023.
- ^ Korstjens, Amanda H.; Lehmann, Julia; Dunbar, R.I.M. (2010). "Resting time as an ecological constraint on primate biogeography". Animal Behaviour. 79 (2): 361–374. doi:10.1016/j.anbehav.2009.11.012. ISSN 0003-3472. S2CID 53199386.
- ^ Kirkpatrick, R.C. 2011. The Asian colobines: diversity among leaf-eating monkeys. In: Primates in Perspective, C.J. Campbell, A. Fuentes, K.C. MacKinnon and M. Panger (eds.), pp. 189–202. Oxford University Press, Oxford, UK.
- ^ a b Harding, Lee E. (2010-01-25). "Trachypithecus cristatus (Primates: Cercopithecidae)". Mammalian Species. 42: 149–165. doi:10.1644/862.1. ISSN 0076-3519.
- ^ "How CITES works | CITES". www.cites.org. Retrieved 2020-04-07.
- ^ Van Tran, Bang; Nguyen, Minh Anh; Nguyen, Dat Quoc; Truong, Quan Bich Thi; Ang, Andie; Covert, Herbert H.; Hoang, Duc Minh (2017). "Current conservation status of Germain's langur (Trachypithecus germaini) in Vietnam". Primates. 58 (3): 435–440. doi:10.1007/s10329-017-0610-2. ISSN 0032-8332. PMID 28492971. S2CID 26470.