Thailand Kantschil

from Wikipedia, the free encyclopedia
Thailand Kantschil
Systematics
Superordinate : Laurasiatheria
Order : Artiodactyla (Artiodactyla)
Subordination : Ruminants (ruminantia)
Family : Stag piglet (tragulidae)
Genre : Tragulus
Type : Thailand Kantschil
Scientific name
Tragulus williamsoni
Kloss , 1916

The Thailand Kantschil ( Tragulus williamsoni ) is a little researched mammal from the family of stag piglets (Tragulidae). It occurs in northern Thailand and probably in southern China , where it may prefer river banks in lowlands. It is largely only known from one individual plus a few skulls. Like all deer piglets, he has a small stature. Its fur is uniformly colored ocher brown. No information is available on the animals' way of life. The Thai Kantschil was scientifically named in 1916. For a long time, however, it was considered a subspecies of the Kleinkantschil . It was only provisionally raised to species level in 2004. Nothing is known about the threat to the population.

features

Habitus

The Thailand kantschil is slightly larger than the small kantschil ( Tragulus kanchil ). Dimensions are only available for the holotype copy. This has a head-trunk length of 52.5 cm and a tail length of 7.4 cm. In terms of color, it is similar to the subspecies Tragulus kanchil affinis . It has a uniform ocher-brown color on the back without any strong brown spots. A darker stripe that is difficult to see runs along the neck. The hair on the back ends in black tips. The underside and chin are white. Both areas are separated at the throat by a sloping reddish-brown band. In contrast to this, in the Annam-Kantschil ( Tragulus versicolor ) the throat ligament is not fully developed and the light sections are thus connected to one another. The legs of the Thailand Kantschil are also ocher-colored, lighter on the front limbs towards the outside. On the 4.3 cm long ears, fine, short and dark brown hair covers the outside. The rear foot length is 12.5 cm.

Skull and dentition features

The skull of the specimen copy is 10.3 cm long and up to 4.6 cm wide on the zygomatic arches . The dentition consists of 34 teeth along the dental formula is: . The length of the upper row of teeth is 3.5 cm.

distribution

So far, the species is largely only known from the holotype specimen, which comes from Meh Lem in the Phrae province in northern Thailand . Further individuals from Mengla County in the Chinese province of Yunnan can probably be assigned to the Thailand Kantschil based on the skull dimensions. Furthermore, in 2014 pictures of camera traps in the forest area of Xishuangbanna in Mengla were presented, showing deer piglets with a coat color comparable to that of the Thailand Kantschil. The distribution probably covers a larger area with possible occurrences in Vietnam , Laos and Myanmar .

Way of life

Little is known about the Thai Kantschil way of life. Based on step seals from the areas around Mengman and Longmen in Mengla County of Yunnan, the animals prefer the lower slopes and river valleys in the lowlands. The landscapes are covered with forests of figs and representatives of the genera Baccaurea , Alpinia and Phrynium . There is a preference for habitats with taller trees and thick bushes that offer hiding places. In addition, the Thailand Kantschil often stays near water.

Systematics

The Thailand-Kantschil is a kind from the genus Tragulus within the family of mouse deer (Tragulidae) and the order of the cloven-hoofed animals (Artiodactyla). The deer piglets comprise a total of three genera and are among the smallest cloven-hoofed animals. Within the group of forehead weapon bearers (Pecora) they are classified as basal, which can also be proven by genetic data. The missing forehead arms and the development of the tear duct as a single, elongated opening on the inner edge of the orbit can be seen as special features . The genus Tragulus , together with the Vietnam Kantschil, includes a total of six species, all of which are common in Southeast Asia and southern East Asia . The best known include the Großkantschil ( Tragulus napu ) and the Kleinkantschil ( Tragulus kanchil ). All species are inhabitants of dense forests.

The first scientific description of the Thailand Kantschil was made by Cecil Boden Kloss in 1916. Kloss saw the new form as a subspecies of the Kleinkantschil and accordingly named it Tragulus kanchil williamsoni , but noted the extraordinary size of the animal. A fully grown female is considered a holotype . According to the original description, this comes from the Me Song forest in the northern Thai province of Phrae . In more recent works, Meh Lem in the district of Amphoe Mueang Phrae in said province is usually given as Terra typica . The specific epithet honors WJF Williamson, one of the finders of the specimen copy and at the same time co-editor of the magazine in which the first description appeared.

For the remainder of the 20th century, Kloss' specimen copy remained the only clearly known individual of the Thailand Kantschil. A karyological study published in 1989 on animals from the Chinese province of Yunnan referred to the Thailand Kantschil, but did not present the individuals used for it. The double chromosome set of 2n = 32 listed therein corresponds to that of the other deer piglets that have been examined so far. As a rule, the Thailand Kantschil thus retained its subspecies status. However, he was sometimes listed as Tragulus javanicus williamsoni . This goes back to a two-species concept favored in the 1940s within the genus Tragulus , in which only a distinction was made between the major and minor chilins and the latter was referred to as Tragulus javanicus due to the priority of the name . Skull morphological investigations from 2004 suggested, however, that the Thailand Kantschil could possibly be regarded as an independent species. The authors of the study, Erik Meijaard and Colin P. Groves , justified this with the large size of the skull compared to the small Kantschil and raised the Thailand Kantschil provisionally at the species level, but not without pointing out that this assessment is based on only one examined specimen . In their work-up, they grouped the Thailand Katschil in a Tragulus javanicus group, which in addition to this also includes the Kleinkantschil and the eponymous Java Kantschil . These small- shaped species are compared to the Tragulus napu group with large representatives such as the Großkantschil and the Balabac-Kantschil ( Tragulus nigricans ). A new study from 2017 on two additional, large skulls from Mengla County in Yunnan supports the view of a separate species position of the Thailand Kantschil. In order to be able to determine its taxonomic status more precisely, further analyzes are required, including on the type locality. In individual systematics such as in the revision of the ungulates published by Groves and Peter Grubb in 2011 as well as in the second volume of the standard work Handbook of the Mammals of the World published at the same time , the Thailand Kantschil is considered to be independent.

Hazard and protection

The IUCN lists the Thailand Kantschil in the category "insufficient data" ( data deficient ). In particular, there is a lack of information on the distribution and way of life of the animals, so that no threat to the population can be identified. In the presumed distribution area, however, there is sometimes high hunting pressure on wild animals.

literature

  • Erik Meijaard: Family Tragulidae (Chevrotains). In: Don E. Wilson and Russell A. Mittermeier (Eds.): Handbook of the Mammals of World. Volume 2: Hooved Mammals. Lynx Edicions, Barcelona 2011, ISBN 978-84-96553-77-4 , pp. 320–334 (p. 331)

Individual evidence

  1. ↑ a b c d C. Boden Kloss: On a new mouse-deer from upper Siam. Journal of the Natural History Society of Siam 2, 1916, pp. 88-89 ( [1] )
  2. ↑ a b c d e f g Erik Meijaard: Family Tragulidae (Chevrotains). In: Don E. Wilson and Russell A. Mittermeier (Eds.): Handbook of the Mammals of World. Volume 2: Hooved Mammals. Lynx Edicions, Barcelona 2011, ISBN 978-84-96553-77-4 , pp. 320–334 (p. 331)
  3. ↑ a b c Erik Meijaard, Marcus AH Chua and JW Duckworth and: Is the northern chevrotain, Tragulus williamsoni KLOSS, 1916, a synonym or one of the least-documented mammal species in Asia? The Raffles Bulletin of Zoology 65, 2017, pp. 506-514
  4. ↑ Zhang Mingxia, Cao Lin, Quan Ruichang, Xiao Zhishu, Yang Xiaofei, Zhang Wenfu, Wang Xuezhi and Deng Xiaobao: Camera trap survey of animals in Xishuangbanna Forest Dynamics Plot, Yunnan. Biodiversity Science 22 (6), 2014, pp. 830-832, doi: 10.3724 / SP.J.1003.2014.14064
  5. ↑ Cao Ming, Zhou Wei, Bai Bing, Zhang Qin, Wang Bin and Chen Min-Yong: Habitat Use of Williamson's Mouse-deer (Tragulus williamsoni) in Mengla Area, Southern Yunnan. Zoological Research 31 (3), 2010, pp. 303-309, doi: 10.3724 / SP.J.1141.2010.03303
  6. ↑ Alexandre Hassanin, Frédéric Delsuc, Anne Ropiquet, Catrin Hammer, Bettine Jansen van Vuuren, Conrad Matthee, Manuel Ruiz-Garcia, François Catzeflis, Veronika Areskoug, Trung Thanh Nguyen and Arnaud Couloux: Pattern and timing of diversification of Cetartiodactalia, Lauriala (Mammia ), as revealed by a comprehensive analysis of mitochondrial genomes. Comptes Rendus Palevol 335, 2012, pp. 32-50
  7. ↑ Juan P. Zurano, Felipe M. Magalhães, Ana E. Asato, Gabriel Silva, Claudio J. Bidau, Daniel O. Mesquita and Gabriel C. Costa: Cetartiodactyla: Updating a time-calibrated molecular phylogeny. Molecular Phylogenetics and Evolution 133, 2019, pp. 256-262
  8. ↑ JJM Leinders and Erik Heintz: The configuration of the lacrimal orifices in Pecorans and Tragulids (Artiodactyla, Mammalia) and its significance for the distinction between Bovidae and Cervidae. Beaufortia 30 (7), 1980, pp. 155-160
  9. ↑ a b c Erik Meijaard and Colin P. Groves: A taxonomic revision of the Tragulus mouse-deer (Artiodactyla). Zoological Journal of the Linnean Society 140 (1), 2004, pp. 63-102, doi: 10.1111 / j.1096-3642.2004.00091.x
  10. ↑ Shi L. and Chen Y .: The karyotype analysis of Yunnan mouse deer (Tragulus javanicus williamsoni). Acta Zoologica Sinica 35, 1989, pp. 41-43
  11. ↑ Colin P. Groves and Peter Grubb: Ungulate Taxonomy. Johns Hopkins University Press, 2011, pp. 1–317 (pp. 56–59)
  12. ^ R. Timmins, JW Duckworth and E. Meijaard: Tragulus williamsoni. The IUCN Red List of Threatened Species 2015. e.T136533A61978926 ( [2] ), last accessed July 7, 2020

Web links