Przewalski racing rat

Przewalski racing rat
Systematics
Family : Long-tailed mice (Muridae) Subfamily : Gerbils (Gerbillinae) Tribe : Gerbillini Sub tribus : Rhombomyina Genre : Brachiones Type : Przewalski racing rat
Scientific name of the  genus
Brachiones
Thomas , 1925
Scientific name of the  species
Brachiones przewalskii
( Büchner , 1889)

The Przewalski racing rat ( Brachiones przewalskii ) is a closely with the meriones Related Art of gerbils and the single species of the genus Brachiones . Named after Nikolai Michailowitsch Prschewalski , it was described by Eugen Alexander Büchner in 1889 as Gerbillus przewalskii . It can be distinguished from the racing rats by the construction of the skull and the dentition.

The Przewalski racing rat lives in desert areas in northwest China and is not endangered. The compact body, seven to ten centimeters long without a tail, the shortened ears and the elongated claws of the front paws indicate a digging way of life. The tail length is six to eight centimeters. The fur is pale brown-yellow to light gray on top and white on the underside.

Body features

The body of the Przewalski racing rat is stocky, the ears are shortened and the claws of the front paws are elongated. The soles of the hind paws are densely covered with hair , those of the front paws are hairless. The short fur is pale brown-yellow to light gray on top. The entire underside, front paws and hind paws are white. The shortened, slender and tapering tail is consistently brownish-yellow or whitish and has no tassel . The head-trunk length is 67 to 103 millimeters, the tail length 56 to 78 millimeters, the hind foot length 22 to 24 millimeters, the ear length 6 to 9 millimeters, the largest skull length 24 to 29 millimeters and the body weight 12 to 42 grams. The ear length is about a third of the length of the hind foot including the claws.

The skull is short and wide, the muzzle is short, and the nasal bones are short and narrow. The frontal bone is wide and the cheekbone runs steeply outwards. Characteristic for the Przewalski racing rat are the large eye socket spacing and the wide brain skull. This gives the skull its triangular shape. It differs from the skull of the racing rats in the very short incisor and posterior palatal holes and the hardly developed eustachi tube despite the very large tympanic bubbles .

The upper incisors are straight, i.e. not bent backwards, and have a longitudinal furrow on the front. With the first and second molars , the connections between the toothed strips are very wide and can be found even with moderate wear. Unique among the gerbils is the substantial reduction in size of the anteroconid on the first lower molar, i.e. a secondary reduction in the tooth ridges.

Way of life, distribution and existence

Locations of the Przewalski racing rat in China

The habitat of the Przewalski racing rat are desert areas . It prefers semi-permanent sand dunes overgrown with shrubs or located in the vicinity of wooded areas . The physique suggests that she has developed a burrowing way of life. Compared to other gerbils, the construction system is quite simple. The opening has a diameter of about 4.5 centimeters and the tunnels run no deeper than 60 centimeters. The population density is significantly lower than that of other gerbils.

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

The International Union for Conservation of Nature IUCN classified the Przewalski racing rat in 1996 and 2008 as not endangered (“least concern”). This is justified with the wide distribution, the presumably high population, the lack of essential threats and the improbability of a significant decline in the population. Measures to protect the species of the Przewalski racing rat are not known, but they could occur in protected areas. In 2004 it was also listed as not endangered on the regional Red List of China .

Systematics and nomenclature

The Przewalski racing rat is the only species in the genus Brachiones . Due to several derived features of the skull and the dentition, the genus is clearly delineated. It is probably closely related to the racing rats, with whom it forms a monophyletic group within the "higher gerbils" ( Rhombomyina ). Pawlinow and coworkers (1990), McKenna and Bell (1997), Pawlinow (2003), Musser and Carleton (2005) and Pawlinow (2008) assign them to a tribe Rhombomyini, Untertribus Rhombomyina or Untertribus Merionina comprising the "higher gerbils" . Sokolow and Orlow (1980) consider them to be the same species as the lunchtime rat . Tong (1989), however, considers them to be related to the fat-tailed gerbil . Smith and Hoffmann (2008) distinguish three subspecies :

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

The type specimen of the Przewalski racing rat was found in the Lop Nor desert . Named after Nikolay Przhevalsky it was founded in 1889 by Eugen Alexander Buchner as przewalskii Gerbillus described . The genus Brachiones (from ancient Greek brachion βραχιων, ' arm ') with the type species Brachiones przewalskii was described by Oldfield Thomas in 1925. The German common name “Przewalski racing rat” (Grzimek, 1988; Macdonald, 2004) is used.

literature

Mainly used literature:

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

Web link

• Brachiones przewalskii inthe IUCN Red List of Threatened Species 2013.2. Listed by: AT Smith, CH Johnston, 2008. Retrieved December 22, 2013.

Individual evidence

1. ↑ ^{a b c d e} Nowak, 1999 (“ Brachiones ” p. 1457).
2. ↑ ^{a b c d e f g h} Smith and Hoffmann, 2008 (“Przewalksi's Gerbil” p. 248).
3. ↑ ^{a b c} Smith and Hoffmann, 2008 ("Key to the Chinese Genera of Gerbillinae" p. 248).
4. ↑ ^{a b c d e} Pawlinow, 2008 (“Genus Brachiones Thomas, 1925” pp. 53–54).
5. ^ Smith and Hoffmann, 2008 (card 164).
6. ↑ ^{a b} Musser and Carleton, 2005 ( “ Brachiones przewalskii ” p. 1212).
7. ↑ ^{a b} Malcolm C. McKenna, Susan K. Bell: Classification of Mammals Above the Species Level . Columbia University Press, New York 1997, ISBN 0-231-11012-X , pp. 159 .
8. ^ Gordon Barclay Corbet: The Mammals of the Palaearctic Region. A Taxonomic Review . British Museum (Natural History) / Cornell University Press, London 1978, ISBN 0-8014-1171-8 . → Quoted in: Nowak, 1999 (“ Brachiones ”).
9. ↑ Andrew T. Smith, Charlotte H. Johnston: Brachiones przewalskii . In: IUCN 2008 (Ed.): 2008 IUCN Red List of Threatened Species . ( Full text ).
10. ^ Igor Jakowlewitsch Pawlinow, Ju. A. Dubrowski, Olga Leonidowna Rossolimo, Je. G. Potapowa : Gerbils of the World Fauna . 1990, ISBN 5-02-005350-3 (Russian: Peschanki mirovoĭ fauny .).
11. ^ Igor Jakowlewitsch Pawlinow: Systematics of the mammals of the world . Moscow State University, Moscow 2003 ( full text - Russian: Sistematika sovremennykh mlekopitai ︠ u ︡ shchikh “ Brachiones ” .).
12. ↑ ^{a b} Musser and Carleton, 2005 ( “ Brachiones ” p. 1212).
13. ↑ Wladimir Evgenjewitsch Sokolow, Viktor Nikolajewitsch Orlow: Opredelitel 'mlekopitaûŝih Mongol'skoj Narodnoj Respubliki . Nauka, Moscow 1980, OCLC 944090651 (Russian). → Quoted in: Pawlinow, 2008 (“Genus Brachiones Thomas, 1925” p. 54).
14. ↑ Haiyan Tong: Origine et evolution of Gerbillidae (Mammalia, Rodentia) en Afrique du Nord . In: Mémoires de la Société géologique de France, nouvelle série . No. 155 , 1989, ISBN 2-85363-050-1 , ISSN  0249-7549 , pp. 1-120 . → Quoted in: Pawlinow, 2008 (“Genus Brachiones Thomas, 1925” p. 54).
15. ↑ Oldfield Thomas: The Generic Position of Gerbillus przewalskii . In: Annals and Magazine of Natural History. Series 9 . tape 16 , 1925, pp. 548 . → Quoted in: Musser and Carleton, 2005 ( “ Brachiones ” p. 1212).
16. ↑ Systematic overview of mammals . In: Bernhard Grzimek (Ed.): Grzimek's Enzyklopädie Säugetiere. tape 11 , p. 11–55 , here p. 37 (eleven-volume licensed edition of the original edition from 1988).
17. ↑ List of species . In: David Macdonald (ed.): The great encyclopedia of mammals . Könemann (Tandem-Verlag), Königswinter 2004, ISBN 3-8331-1006-6 , p. 866-889 , here p. 870 (original title: The encyclopedia of mammals . New York 2001.).