Vietnam Kantschil

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Vietnam Kantschil
Systematics
Superordinate : Laurasiatheria
Order : Artiodactyla (Artiodactyla)
Subordination : Ruminants (ruminantia)
Family : Stag piglet (tragulidae)
Genre : Tragulus
Type : Vietnam Kantschil
Scientific name
Tragulus versicolor
Thomas , 1910

The Vietnam Kantschil ( Tragulus versicolor ), also Vietnamese mouse deer or Annam Kantschil called, is a mammal of the family of mouse deer (Tragulidae). The species is endemic to central and southern Vietnam . They are small ungulates with rounded backs and slender limbs, as well as a striking body color, which consists of a silver-gray saddle pad and a brownish shoulder and neck fur. Nothing is known about the way of life of the animals. In general, the Vietnam Kantschil is considered rare. The species was scientifically introduced in 1910, another individual has been documented from 1990. The species was thought to be lost - it was not until almost thirty years later that photos of the animals were taken again. No information is available about the inventory.

features

Habitus

The Vietnam Kantschil reaches a head-trunk length of around 40 cm, a tail length of around 5 cm and a weight of a good 1.7 kg. The ear length is 3.5 cm, the rear foot length 11 cm. The dimensions given refer to a single individual from the Tra River in central Vietnam . Outwardly, the Vietnam Kantschil resembles the other deer piglets with its small body size, the rounded, backwards rising back and the long and slender limbs. The animals have a distinct saddle pad on the back . The fur here is colored silver-gray and comparatively dense. The individual hairs have white tips. The fur on the shoulders and neck is clearly brownish. It is less dense here than on the back and is noticeably coarse, but does not have the prickly character of the small Kantschil ( Tragulus kanchil ). The darker coat pattern on the neck, which often occurs in other deer piglets, is not developed in the Vietnamese Kantschil. A white hair dominates the belly, which stands out sharply from the silver-gray sides. In contrast to the Kleinkantschil, the white belly is not interrupted by a darker longitudinal stripe. The white fur color continues all the way to the chin. In the area of ​​the throat, however, it fans out into several bands, which is typical of the deer piglets. Some individuals of the Vietnam Kantschil have a sequence of three white and two dark stripes, which is reminiscent of the Java Kantschil ( Tragulus javanicus ). Others have for the greater mouse-deer ( Tragulus Napu white) typical five stripes, alternating with four dark stripes. On the head, the Vietnam Kantschil lacks the distinctive dark longitudinal stripes of other tragulus species that run from the eyes to the nose.

Skull and dentition features

The skull is on average 9.1 cm long and 4.3 cm wide at the zygomatic arches . Compared to other members of the genus Tragulus , it is small, but significantly wider. The inflated tympanic membranes , each 1.8 cm long and 0.9 cm wide, and the elongated nasal bone are striking . The lower jaw measures approximately 3 inches in length. The teeth 34 is composed of teeth with the following tooth formula : . As with all deer piglets, the upper canine teeth are dagger-shaped and large in the Vietnamese Kantschil.

Distribution and way of life

Distribution area of ​​the Vietnam Kantschil

The Vietnam-Kantschil is known from two regions in Vietnam : on the one hand from the area around Nha Trang in the southern part and from the area around the river Tra near the villages of Dak Rong and Buon Luoi in the central part of the country. Both landscape areas are covered with deciduous and evergreen tropical rainforests . The altitude ranges from sea level up to 500 m. On the Bo River, the species occurs together with the Kleinkantschil. No information is available on the way of life.

Systematics

The Vietnam 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, which represent a total of three genera and are among the smallest cloven-hoofed animals, are considered to be the basal group of forehead weapon bearers (Pecora), which can also be demonstrated using genetic data. Special features can be found in the lack of forehead arms and in the development of the tear duct , which has only a single, but elongated opening on the inner edge of the orbit . The generic Tragulus be assigned together with the Vietnam Kantschil total of six species, all in Southeast Asia and southern Asia are common. Mainly known are the Großkantschil ( Tragulus napu ) and the Kleinkantschil ( Tragulus kanchil ). All species inhabit dense forests.

Oldfield Thomas

The first scientific description of the Vietnam Kantschil comes from Oldfield Thomas from 1910. He had four individuals available for this. As a holotype , he selected a male animal of 48 cm length, which had been collected in March 1906 by J. Vassal near Nha Trang in southern Vietnam. The region thus represents the type area of ​​the species. The species designation versicolor refers to the characteristic color of the fur. Thomas saw the Vietnam Kantschil in his first description as more closely related to the Großkantschil, but emphasized the smaller size of its new species. He then assigned him to a T. napu group, whose unifying characteristics include the coarse hair on the back of the neck and large canine teeth. This he in turn set off from a group around the Kleinkantschil ( T. kanchil group). In the 1930s and 1940s, Frederick Nutter Chasen combined all known representatives of the tragulus genus in the two best-known species, the large and the small cantschil, in a series of articles on the mammalian fauna of Southeast Asia . According to his opinion, the Vietnam Kantschil belonged to the Greater Kantschil, which he equated scientifically with the Java Kantschil ( Tragulus javanicus ). Only Adriaan Cornelis Valentin van Bemmel pointed out in 1949 that the Großkantschil is not native to Java , whereby the group fell back to Tragulus napu as the next available name.

For the further course of the 20th century, the status of the Vietnam Kantschil was largely retained as a subspecies of the Greater Kantschil. In a 2004 study, Erik Meijaard and Colin P. Groves revised the genus Tragulus and split it into a total of six species. The division was based on morphometric and morphological analyzes. Both authors differentiated a T. napu group with the Großkantschil and the Balabac-Kantschil ( Tragulus nigricans ) and a T. javanicus group with the Java-Kantschil, the Kleinkantschil and the Thailand-Kantschil ( Tragulus williamsoni ). The respective groups set themselves apart by their height. They classified the Vietnam Kantschil as independent, as it differed significantly with its relatively small but wide skull and the typical coat color and the sometimes coarse hair on the neck. So they put him in their own T. versicolor group as the only member. In a general revision of the ungulates from 2011, Groves and Peter Grubb again confirmed the results of the previous investigations.

Threat and protection

Information on the size of the population and the endangerment of the Vietnam Kantschil population is not available. The species was previously only known from around half a dozen individuals. Four of them go back to the Vassals collection in 1906, which come from the area around Nha Trang. Researchers on a Vietnamese-Russian expedition received another individual from local hunters in 1990. The animal was shot near the Tra River in Gia Lai Province, central Vietnam . After that, the Vietnam Kantschil was not sighted for almost three decades and was considered lost. Only during research work by Vietnamese scientists between 2017 and 2018 could the species be proven again by camera traps in several locations in the vicinity of Nha Trang. Over 2000 photos of the animals were taken. The IUCN lists the species in the “ data deficient ” category due to lack of information . The deforestation of the rainforests in the known distribution area of ​​the Vietnam-Kantschil and, most likely, hunting can be seen as a possible threat. In principle, a more detailed study of the distribution and way of life of the animals is necessary.

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. 330)

Individual evidence

  1. ↑ a b c German V. Kuznetsov and Alex. V. Borissenko: A new record of Tragulus versicolor (Artiodactyla, Tragulidae) from Vietnam, and its sympatric occurence with T. kanchil. Russian Journal of Theriology 3 (1), 2004, pp. 9-13
  2. ↑ a b c d 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. 330)
  3. ↑ a b 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
  4. ↑ Erik Meijaard, Marcus AH Chua and JW Duckworth: Is the northern chevrotain, Tragulus williamsoni Kloss, 1916, a synonym or one of the least-documented mammal species in Asia ?. Raffles Bulletin of Zoology 65, 2017, pp. 506-514
  5. ↑ 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
  6. ↑ 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
  7. ↑ 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
  8. ^ A b Oldfield Thomas: Three new Asiatic mammals. The Annals and Magazine of Natural History 8 (5), 1910, pp. 534-536 ( [1] )
  9. ^ Adriaan Cornelis Valentin van Bemmel: On the meaning of the name Cervus javanicus Osbeck 1765 (Tragulidae). Treubia 20, 1949, pp. 378-380
  10. ↑ Colin P. Groves and Peter Grubb: Ungulate Taxonomy. Johns Hopkins University Press, 2011, pp. 1–317 (pp. 56–59)
  11. ↑ Erik Meijaard, Alex. V. Borissenko and German V. Kuznetsov: The rediscovery of Tragulus versicolor, the Silver-backed Chevrotain. Oryx 38 (3), 2004, pp. 254-255
  12. ↑ To Nguyen, Van Bang Tran, Duc Minh Hoang, Thi Anh Minh Nguyen, Dinh Thang Nguyen, Van Tiep Tran, Barney Long, Erik Meijaard, Jeff Holland, Andreas Wilting and Andrew Tilker: Camera-trap evidence that the silver-backed chevrotain Tragulus versicolor remains in the wild in Vietnam. Nature Ecology & Evolution, 2019, doi: 10.1038 / s41559-019-1027-7
  13. ^ R. Timmins, JW Duckworth and E. Meijaard: Tragulus versicolor. The IUCN Red List of Threatened Species 2015. e.T136360A61978789 ( [2] ), last accessed on November 16, 2019

Web links

Commons : Tragulus versicolor  - collection of images, videos and audio files