Slender shrew
| Slender shrew | ||||||||||||
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| Scientific name | ||||||||||||
| Sorex gracillimus | ||||||||||||
| Thomas , 1907 |
The slim shrew ( Sorex gracillimus ) is a species of shrew from the genus of the red- toothed shrew ( Sorex ). It is found in parts of Russia including Sakhalin Island and the Kuril Islands , the north of the People's Republic of China , Korea, and Japan .
features
With a head-trunk length of 4.8 to 5.2 centimeters, the slim shrew is one of the medium-sized shrew species. The tail reaches a length of 37 to 43 millimeters - and is therefore only slightly shorter than the rest of the body - the rear foot is 10 to 11 millimeters.
| 1 | · | 5 | · | 1 | · | 3 | = 32 |
| 1 | · | 1 | · | 1 | · | 3 |
The skull has a total length of no more than 17 millimeters. 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 third and usually smaller than the first. Compared to most of the members of the S. minutus group, the skull is almost round instead of oval, and it begins very abruptly behind the rostrum.
The genome of the slender shrew consists of a diploid chromosome set of 2n = 36, (FN = 62).
distribution
The distribution area of the slim shrew is in the extreme northwest of the Asian continent and the offshore islands. The species is found in parts of Russia including Sakhalin Island and the Kuril Islands , north of the People's Republic of China , Korea, and Japan . In China, the deposits are limited to the extreme north in the provinces of Heilongjiang , Nei Mongol and Jilin . In Japan, the species lives on the islands of Shikotan , Hokkaidō , Rishiri and Rebun .
Way of life
The slender shrew lives in most of its range in coniferous forests in mountain regions, but it also occurs in alluvial forests , grassy areas and bamboo forests. The densest occurrences are documented from mixed forest stands and alluvial forests on rivers, while avoiding short grass pastures and fields. In the secondary forest , the densities are greater than in the original boreal coniferous forest (taiga). In most of the distribution area the species lives allopatric with the pygmy shrew ( Sorex minutus ).
Like all shrews, this species also feeds on invertebrates, especially prey on the litter and the top soil layers such as earthworms and insects and their larvae. The breeding season extends from May to October, the females throw one to eight, on average six, young.
Systematics
The slim 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 1907, who described an individual from the Russian island of Sakhalin , together with the type of Sorex daphaenodon, also discovered there . Within the genus, the species is classified in the subgenus Sorex and assigned to the S. gracillimus group. It was partially assigned to the pygmy shrew, but is now considered an independent species due to numerous characteristics.
Within the species, in addition to the nominate form Sorex gracillimus gracillimus with Sorex gracillimus granti , Sorex gracillimus hyojironis , Sorex gracillimus minor and Sorex gracillimus natalae, four further subspecies are distinguished.
Threat and protection
The species occurs regularly but not often in its range on the Asian mainland. On the island of Sakhalin and the Kuril Islands, however , Sorex gracillimus is the most common species. In Japan it occurs regularly in the east and north, but not in the south and west.
The International Union for Conservation of Nature and Natural Resources (IUCN) classifies the slender shrew as not endangered (least concern) due to its relatively large distribution area and large populations as well as the absence of a threat to the population.
literature
- Robert S. Hoffmann, Darrin Lunde: Slender 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 , pp. 316-317.
Web links
- Sorex gracillimus inthe IUCN 2013 Red List of Threatened Species . Posted by: H. Abe, SD Ohdachi, K. Tsytsulina, 2008. Retrieved January 2, 2014.
supporting documents
- ↑ a b c d e Robert S. Hoffmann, Darrin Lunde: Slender 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 , pp. 316-317.
- ↑ a b c d e Sorex gracillimus ( 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 e f Sorex gracillimus in the IUCN Red List of Threatened Species 2013.2. Posted by: H. Abe, SD Ohdachi, K. Tsytsulina, 2008. Retrieved January 2, 2014.
