Przewalski's gerbil

The Przewalski's race rat ( Brachiones przewalskii ) is a closely related with the racing rats type of gerbils and the only species of the genus Brachiones. Named after Nikolai Mikhailovich Przhevalsky it was described in 1889 by Eugen przewalskii Alexander Buchner as Gerbillus. From the racing rats can be distinguished by the construction of the skull and dentition.

The Przewalski rat race inhabited desert areas in northwest China and is not endangered. The no tail seven to ten inches long, compact body, the shorter ears and elongated front claws indicate a grave lifestyle. The tail length is six to eight inches. The coat is pale brown upper side yellow to light gray and white hand.

Body characteristics

The body of the Przewalski's race rat is penetrated, the ears are shortened and the front claws are extended. The soles of the hind feet are densely covered with hairs, those of the front feet are hairless. The short coat is pale brown upper side yellow to light gray. The entire underside of the front paws and back paws are white. The condensed, slim and tapered tail is consistently brown yellowish or whitish and has no tassel on. The head-body length is 67-103 mm, tail length 56-78 mm, the Hinterfußlänge 22 to 24 millimeters, the ear length of 6-9 mm, the greatest length of skull 24 to 29 mm and body weight 12 to 42 grams. The ear length is about one third of the Hinterfußlänge including claws.

The skull is short and broad, the muzzle is short and the nasal bones are short and narrow. The frontal bone is wide and the cheekbone is steep outward. Characteristic of the Przewalski rat race are the large orbital distance and the wide cranium. This gives the skull its triangular shape. From the skull of the rat race, it differs by the very short incisor and posterior palatal holes and hardly developed despite very large bullae eustachian tube.

The upper incisors are straight, not bent rearwardly and have a longitudinal groove on the front side. In the first and second molars, the connections between the racks are very broad and can be found even at moderate abrasion. Unique among the gerbils is the essential reduction of Anteroconid the first lower molar tooth, so a secondary reduction of the racks.

Lifestyle, distribution and population

The habitat of the Przewalski rat race are desert areas. It prefers semi- permanent, overgrown with shrubs or are going through wooded areas near sand dunes. The body indicates that it has developed a grave lifestyle. Compared to other gerbils, the construction system is quite simple. The opening has a diameter of about 4.5 centimeters and the passages do not extend deeper than 60 cm. The population density is significantly lower than other gerbils.

The distribution of Przewalski rat race are dry areas in China. It inhabits the deserts of northern Xinjiang, Gansu over the north to the west of Inner Mongolia north of the Tianshan. It is only known from the Holocene of China and does not occur in Mongolia.

The World Conservation Union IUCN classified the Przewalski rat race in 1996 and 2008, no impairment ( " least concern "). This is justified by the widespread, probably the high inventory, the lack of significant threats, and the unlikelihood of a significant stock decline. Measures for the conservation of Przewalski rat race are not known, but it may occur in protected areas. In the regional Red List of China in 2004, she was also conducted as not at risk.

Systematics and Nomenclature

The Przewalski rat race is the only species of the genus Brachiones. Following a number of derived features of the skull and dentition, the genus is clearly delineated. It is probably closely related to the rat race, with which it forms a monophyletic group within the "higher gerbils " ( Rhombomyina ). Pawlinow and colleagues ( 1990), McKenna and Bell ( 1997), Pawlinow (2003), Musser and Carleton (2005) and Pawlinow (2008) assign them to the "higher Gerbils " comprehensive Rhombomyini tribe, subtribes Rhombomyina or subtribes Merionina. Sokolov and Orlov (1980 ) consider them the same way as the noon race rat. Tong (1989 ), however, for it holds related to the fat -tailed gerbil. Smith and Hoffmann ( 2008) distinguish three types:

• Przewalskii przewalskii Brachiones ( Buchner, 1889) in Xinjiang and Gansu,
• Brachiones przewalskii arenicolor (Miller, 1900) in Xinjiang in the west of the Tarim Basin and
• Brachiones przewalskii callichrous Geptner, 1934 in Inner Mongolia.

The type specimen of the Przewalski's race rat was found in the desert of Lop Nor. Named after Nikolai Mikhailovich Przhevalsky it was described in 1889 by Eugen przewalskii Alexander Buchner as Gerbillus. The genus Brachiones ( from Ancient Greek brachion βραχιων, arm ') with the type species Brachiones przewalskii described Oldfield Thomas in 1925 as a German common name is " Przewalski rat race " ( Grzimek, 1988; 2004 Macdonald ). Use.

Literature and References

Mainly used literature:

• Guy G. Musser, Michael D. Carleton: Super Muroidea. In: Don E. Wilson, DeeAnn M. Reeder (eds): Mammal Species of the World. A Taxonomic and Geographic Reference. 3rd edition. Johns Hopkins University Press, Baltimore, 2005, ISBN 0-8018-8221-4, pp. 894-1531 ( full text of the anthology ).
• Ronald M. Nowak: Walker's Mammals of the World. 6th edition. Johns Hopkins University Press, Baltimore / London 1999, ISBN 0-8018-5789-9 (1936 pages).
• Igor Yakovlevich Pawlinow: A review of phylogeny and classification of Gerbillinae (Mammalia: Rodentia ). In: Soologitscheskije issledowanija. No. 9, 2008, ISSN 1025- 532x, pp. 1-68 ( original Russian title of the anthology: Зоологические исследования ).
• Andrew T. Smith, Robert S. Hoffmann: subfamily Gerbillinae. In: Andrew T. Smith, Yan Xie (eds): A Guide to the Mammals of China. Princeton University Press, Princeton / Oxford 2008, ISBN 978-0-691-09984-2, pp. 247-252.

References:

Weblink

• Brachiones przewalskii in the Red List of Threatened Species IUCN 2013.2. Posted by: Smith, A.T. & Johnston, CH, 2008. Retrieved on December 22, 2013

• Gerbils