Vietnamese mole
| Vietnamese mole | ||||||||||||
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| Scientific name | ||||||||||||
| Euroscaptor subanura | ||||||||||||
| Kawada , Son & Can , 2012 |
The Vietnamese mole ( Euroscaptor subanura ) is a species of mammal belonging to the genus of the Southeast Asian moles within the moles (Talpidae). The distribution area extends over the lowlands of northern Vietnam . There the animals live in deciduous forests, but little information is available about their way of life. Characteristics of the species are the small size, an elongated body, a dark fur and a very short tail. An anatomical peculiarity can be found in the thickened ribs. The Vietnamese mole was scientifically introduced in 2012. The threat to the population is unknown.
features
Habitus
The Vietnamese mole is one of the smallest representatives of the Southeast Asian moles. Its head-trunk length varies from 11.0 to 13.3 cm, the tail length is 0.4 to 0.5 cm. This means that the tail only reaches an average of 3.6% of the length of the rest of the body, which is the lowest value compared to other Southeast Asian moles. Some of the animals examined from the eastern part of the range on Ba Vì have tails that are on average 0.6 to 0.7 cm and a ratio of around 5.6%, and then reaches the dimensions of the Pakho mole ( Euroscaptor parvidens ). The tail remains completely hidden under the fur. The body weight varies from 33.8 to 43.0 g. Outwardly, the Vietnamese mole is reminiscent of the Pakho mole. The body is slim and elongated. The fur appears dark brown on the back and silvery brown on the belly. Parts of the neck of the forelegs and the abdomen are blotchy dark orange. The muzzle is elongated and naked, it thickens towards the back. On the underside, it is covered by wart-like humps from which whitish vibrissae sprout. The humps are in rows, which in turn are arranged at an angle to each other. The nostrils open to the side, the nasal pad is round and protrudes forward. The eyes are covered by a transparent lid and are exposed. The front feet have an average length of 1.5 cm and a width of 1.4 cm, the rear feet are 1.4 cm long.
Skull and dentition features
The skull becomes 32.6 to 33.0 mm long. It is smaller, shorter and wider than that of the long-nosed mole ( Euroscaptor longirostris ). The zygomatic arches start at the back of the cheekbones and run almost parallel to each other with only a slight curvature in the front area. The tympanic bladder is inflated and the front area bulges forward, which corresponds to the Pakho mole and differs from the long-nosed mole with its flattened tympanic bladder. The crown process of the lower jaw ends broadly.
In teeth 44 teeth are generally with the following tooth formula is formed: . In the upper dentition the incisors decrease in size from front to back, the entire row of incisors forms a triangle, in the lower dentition, however, the first two incisors are almost the same size and protrude beyond the last. The upper canine and all upper premolars each have two roots. The first premolar is larger than the second and almost the same size as the third. There is a small minor cusp on each of the crowns of the tooth, while the main cusp on the fourth premolar is well developed and large. In the lower jaw, in contrast to most representatives of the Southeast Asian moles, the premolars show only slight fluctuations in size. The foremost premier tooth is also smaller than in other species and only exceeds the canine tooth by 1.5 times. The molars also be characterized by sharp bumps like other moles. In the front two upper molars, the metaconus protrudes over the paraconus on the lip side, which is not the case with the pakho or long-nosed mole. On the last upper molar, the relationship between the two cusps is more balanced. The mesostyle, a small hump between these two main humps, is not divided. In this regard, the Vietnamese mole is similar to the Pakho mole, but differs from other Euroscaptor species. In the lower jaw, on the lip side, the protoconid reaches twice the height of the hypoconid. The former is also shifted backwards, making the trigonid, the raised area of the tooth with the main bumps, narrower than in other species. Furthermore, the talonid, the lower lying area of the molar, into which one of the main cusps of the maxillary molars engages when the bite is closed, was missing an additional small minor cusp, the hypoconulid. This creates a short diastema between the molars that is not found in other species of Southeast Asian moles. The length of the upper row of teeth is about 12.2 mm, that of the lower 11.5 mm. The molars occupy 5.0 and 5.3 mm respectively.
Skeletal features
The spine consists of 7 cervical, 13 thoracic, 6 lumbar, 6 sacrum and 9 tail vertebrae, making a total of 41. The number of caudal vertebrae is small, with most of the other representatives of the Southeast Asian moles it is 12 to 14. The ribs are distinctive, each of which has a broad shape and is very close together due to their backward bent approaches, which corresponds to the rib cage gives an "armored" impression. It is a unique feature of the Vietnamese mole. The pelvis is slender and short, especially on the ischium . Around two thirds of the length of the pelvis is taken up by the connection of the ischium and iliac bone with the sacrum . The humerus resembles that of other moles, but is more delicate than the long-nosed mole and shorter than the pakho mole.
distribution
The Vietnamese mole is found in northern Vietnam . The distribution area is distributed over several provinces, it extends in the south from the province Nghệ An to the north over the provinces Phú Thọ and Vĩnh Phúc to the province Tuyên Quang . In the east it extends to the massif of Ba Vì . The exact borders are not known, to the south the range of the Pakho mole joins, to the north that of Euroscaptor kuznetsovi and Mogera latouchei . Since moles rarely appear together in one area, these seem to be limiting factors for the spread of the Vietnamese mole. The habitat includes the partly deciduous forests and low limestone ridges of the lowlands. So far, the species has not been found in grasslands and farm areas adjacent to forests. The altitude distribution has so far been limited to 200 to 300 m. Euroscaptor kuznetsovi is also recorded in the province of Vĩnh Phúc , but this species lives in much higher mountains.
Way of life
Little is known about the way of life. The animals dig underground tunnels, leaving behind large ejecta mounds. But above-ground paths have also been documented. Animals collected in November and December had little enlarged testicles or a poorly developed uterus , and no captured female has so far carried fetuses . However, one male had swollen testicles in January, so the mating season may take place in the period after that.
Systematics
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Internal systematics of the Southeast Asian moles according to Zemlemerova et al. 2016
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The Vietnamese mole is an independent species within the genus of the Southeast Asian moles ( Euroscaptor ), to which nine more are assigned. The Southeast Asian moles in turn belong to the mole family (Talpidae) and form part of the tribe of the actual moles (Talpini) within them . These consist of the mostly digging representatives of the moles, while other members of the family only live partially underground, move above ground or are adapted to a semi-aquatic way of life. According to molecular genetic studies, the Southeast Asian moles can be divided into two kinship groups, the western longirostris group around the long-nosed mole ( Euroscaptor longirostris ) and the eastern parvidens group around the pakho mole ( Euroscaptor parvidens ). The latter represents the closest relative of the Vietnamese mole. The Vietnamese mole also differs from this in the karyotype . It consists of 2n = 38 chromosome pairs , which are composed of 14 metacentric, 6 subtelocentric and 16 acrocentric autosomes . The X chromosome is small and metacentric, the Y chromosome is also small and speckled. The Pakho mole, on the other hand, only has 36 pairs of chromosomes, other Southeast Asian moles 34.
The first scientific description of the Vietnamese mole was made in 2012 by a research team led by Shin-Ichiro Kawada . She was preceded by several expeditions in 2007 and 2008 to the Tam-Đảo Mountains in the North Vietnamese provinces of Vĩnh Phúc and Tuyên Quang . There, the occurrence of a mole species in higher mountain areas was known (originally assigned to the long-nosed mole, but described as Euroscaptor kuznetsovi in 2016 ). A local resident informed the expedition members about small moles at the foot of the mountains. A total of six individuals were caught during the field research, which served as the basis for the description. The holotype is a fully grown male from the Sơn Dương district in the Tuyên Quang province. The species name subanura is made up of the Latin prefix sub- for "under-" or "near" and an- for "not-" and the Greek word ουρά ( ourá ) for "tail". So translated it means something like "almost without a tail" and refers to the defining anatomical feature.
Threat and protection
Due to insufficient information on distribution, ecology and potential dangers, Euroscaptor subanura is listed by the IUCN in the category “ data deficient ” . The animals come in several protected areas before, so the National Park Tam Đảo , the National Park Xuan Son and in the National Park Ba Vì , also still in the nature reserve Na Hang Nature Reserve and Pu Huong.
literature
- Shin-Ichiro Kawada, Nguyen Truong Son and Dang Ngoc Can: A new species of mole of the genus Euroscaptor (Soricomorpha, Talpidae) from northern Vietnam. Journal of Mammalogy 93 (3), 2012, pp. 839-850 doi : 10.1644 / 11-MAMM-A-296.1
- Boris Kryštufek and Masaharu Motokawa: Talpidae (Moles, Desmans, Star-nosed Moles and Shrew Moles). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths, Colugos. Lynx Edicions, Barcelona 2018, pp. 552–620 (p. 618) ISBN 978-84-16728-08-4
Individual evidence
- ↑ a b c A. V. Abramov, AV Shchinov and Tran Quang Tien: Insectivorous mammals (Mammalia: Eulipotyphla) of the Ba Vi National Park, Northern Vietnam. Proceedings of the Zoological Institute RAS 317 (3), 2013, pp. 221-225
- ↑ a b c d e f g h Shin-Ichiro Kawada, Nguyen Truong Son and Dang Ngoc Can: A new species of mole of the genus Euroscaptor (Soricomorpha, Talpidae) from northern Vietnam. Journal of Mammalogy 93 (3), 2012, pp. 839-850
- ↑ a b c Boris Kryštufek and Masaharu Motokawa: Talpidae (Moles, Desmans, Star-nosed Moles and Shrew Moles). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths, Colugos. Lynx Edicions, Barcelona 2018, pp. 552–620 (p. 618) ISBN 978-84-16728-08-4
- ↑ a b c d E. D. Zemlemerova, AA Bannikova, VS Lebedev, VV Rozhnov and AV Abramov: Secrets of the underground Vietnam: an underestimated species diversity of Asian moles (Lipotyphla: Talpidae: Euroscaptor). Proceedings of the Zoological Institute RAS 320 (2), 2016, pp. 193-220
- ↑ a b Akio Shinohara, Shin-ichiro Kawada, Nguyen Truong Son, Dang Ngoc Can, Shinsuke H. Sakamoto and Chihiro Koshimoto: Molecular phylogenetic relationships and intra-species diversities of three Euroscaptor spp. (Talpidae: Lipotyphla: Mammalia) from Vietnam. Raffles Bulletin of Zoology 63, 2015, pp. 366-375
- ↑ Kai He, Akio Shinohara, Kristofer M. Helgen, Mark S. Springer, Xue-Long Jiang and Kevin L. Campbell: Talpid Mole Phylogeny Unites Shrew Moles and Illuminates Overlooked Cryptic Species Diversity. Molecular Biology and Evolution 34 (1), 2016, pp. 78-87
- ^ Gerrit S. Miller: Notes on Some Moles from Southeastern Asia. Journal of Mammalogy 21 (4), 1940, pp. 442-444
- ^ Robert S. Hoffmann and Darrin Lunde: Genus Euroscaptor. In: Andrew T. Smith and Yan Xie (Eds.): A Guide to the Mammals of China. Princeton University Press, Princeton New Jersey, 2010, pp. 322-323
- ↑ P. Engelbrektsson: Euroscaptor subanura. The IUCN Red List of Threatened Species 2016 :. e.T45955241A45973076 ( [1] ); last accessed on May 4, 2018
Web links
- Euroscaptor subanura in the endangered Red List species the IUCN 2017. Posted by: P. Engelbrektsson, 2013. Accessed May 5 2018th