Tien Shan shrew
| Tien Shan shrew | ||||||||||||
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| Sorex asper | ||||||||||||
| Thomas , 1914 |
The Tien Shan shrew ( Sorex asper ) is a species of shrew from the genus of the red -toothed shrew ( Sorex ). It occurs in the Tian Shan in the People's Republic of China in the eastern Xinjiang autonomous region as well as in western Kazakhstan and northern Kyrgyzstan .
features
With a head-torso length of 5.5 to 7.7 centimeters and a weight of about 5 to 12 grams, the Tien Shan shrew is one of the medium-sized shrew species. The tail reaches a length of 32 to 47 millimeters - and is thus shorter than the rest of the body - the rear foot is 10 to 14 millimeters.
| 1 | · | 5 | · | 1 | · | 3 | = 32 |
| 1 | · | 1 | · | 1 | · | 3 |
The skull has a total length of 19 to 20 millimeters and a width of 9.1 to 9.5 millimeters with a long rostrum (snout region). As most species of the genus has the type in the maxilla per half an incisor (incisor) and then five unicuspid teeth, a Vorbackenzahn (premolar) and three molars (molar). In the lower jaw, however, it has a single canine behind the incisor. Overall, the animals have a set of 32 teeth. The tooth roots are colored red as in most red-toothed shrews. The second single-pointed tooth of the upper jaw is significantly larger than the first and third, the fourth in turn much smaller than the third. The tips of the teeth point slightly backwards and the tips of the single-point teeth form a convex (outwardly curved) line. S. asper differs from the very similar S. excelsus , S. araneus and S. tundrensis in the proportions of the single-pointed teeth.
The genome of the Tien Shan shrew consists of a diploid chromosome set of 2n = 32/33 (FN = 58).
distribution
The Tien Shan shrew occurs in the Tian Shan in the People's Republic of China in the eastern Xinjiang autonomous region as well as in western Kazakhstan and in northern Kyrgyzstan . The altitude distribution is probably between 2000 and 3000 meters.
Way of life
As is the case with many species of the genus, only little data is available on the way of life of this species. The Tien Shan shrew is likely a high mountain specialist like Sorex cansulus or Sorex excelsus . It lives in coniferous forests, moist mountain meadows and bushes in the high mountains over 2000 meters above sea level, preferring habitats with a thick layer of leaves that freeze quickly. It is active throughout the year, mainly at dusk and at night and rarely during the day.
Like all shrews, these species feed on invertebrates, mostly insects. The breeding season begins in late March or early April. The testes of males swell during this period of usually one to two millimeters in size of up to six millimeters and remain active until the end of July. The females give birth to one to eight young animals, an average of 5.3. From July these leave the parents' building.
Systematics
The Tien Shan shrew is classified as an independent species within the genus of the red -toothed shrew ( Sorex ), which consists of around 80 species. The first scientific description comes from Thomas from 1916, who described an individual from the Tekes region, Xinjiang Autonomous Region , in the Tian Shan . The species was partially assigned to S. araneus as a subspecies. Within the genus, the species is classified in the subgenus Sorex and assigned to the S. tundrensis group, although they are not genetically closely related.
Apart from the nominate form Sorex asper asper, no further subspecies are distinguished within the species .
Threat and protection
The Tien Shan shrew is classified by the International Union for Conservation of Nature and Natural Resources (IUCN) as not endangered (least concern) due to its relatively large distribution area and the non-existent threat to the population.
literature
- Robert S. Hoffmann, Darrin Lunde: Tian Shan Shrew. In: Andrew T. Smith , Yan Xie: A Guide to the Mammals of China. Princeton University Press, Princeton NJ 2008, ISBN 978-0-691-09984-2 , p. 314.
Web links
- Sorex asper inthe IUCN 2013 Red List of Threatened Species . Posted by: K. Tsytsulina, 2008. Retrieved January 1, 2014.
supporting documents
- ↑ a b c d e f Robert S. Hoffmann, Darrin Lunde: Tian Shan Shrew. In: Andrew T. Smith , Yan Xie: A Guide to the Mammals of China. Princeton University Press, Princeton NJ 2008, ISBN 978-0-691-09984-2 , p. 314.
- ↑ a b c d e Sorex asper ( Memento of the original from January 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . In: Don E. Wilson , DeeAnn M. Reeder (Eds.): Mammal Species of the World. A taxonomic and geographic Reference. 2 volumes. 3. Edition. Johns Hopkins University Press, Baltimore MD 2005, ISBN 0-8018-8221-4 .
- ↑ a b c d Sorex asper in the Red List of Threatened Species of the IUCN 2013.2. Posted by: K. Tsytsulina, 2008. Retrieved January 1, 2014.
