Eversmann dwarf hamster

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Eversmann dwarf hamster
Systematics
Subordination : Mouse relatives (Myomorpha)
Superfamily : Mice-like (Muroidea)
Family : Burrowers (Cricetidae)
Subfamily : Hamster (Cricetinae)
Genre : Medium dwarf hamster ( Allocricetulus )
Type : Eversmann dwarf hamster
Scientific name
Allocricetulus eversmanni
( Brandt , 1859)

The Eversmann dwarf hamster ( Allocricetulus eversmanni ) is a species of hamster belonging to the medium-sized dwarf hamsters . He inhabits the steppes and semi-deserts of northern Kazakhstan and neighboring Russia . The International Union for Conservation of Nature IUCN classifies it as not endangered . Some systematists assign it to the Mongolian dwarf hamster as an eastern subspecies.

The head-trunk length of the Eversmann dwarf hamster is 9.3 to 16.0 centimeters. The fur is monotonous dark brown in the west to rust-brown-sand-colored in the east of the distribution area and white or gray-white on the underside. There is a rust-brown or gray patch on the chest between the front legs. The number of chromosomes is 26.

Body features

Body measurements and weight

The tail of the Eversmann dwarf hamster is 17 to 28 millimeters long, the length of the hind paws is 15 to 20 millimeters and that of the auricles is 12 to 18 millimeters. The body weight is 36 to 95 grams.

Body measurements and weight of the Eversmann dwarf hamster
Body measurements in millimeters according to Flint after Smith and Hoffmann
Head to torso length 136 to 160 93 to 115
Length of the tail 20 to 28 17 to 28
Length of the hind paws 16 to 20 15 to 18
Length of the auricles 13 to 18 12 to 16
greatest length of the skull   30 to 33
Body weight in grams to Pavlinow after Smith and Hoffmann
body weight to 95 36 to 60

Fur and color

The hair on the upper side is dark gray at the base and the fur of the Eversmann dwarf hamster is darker than that of the Mongolian dwarf hamster. The sides of the body and the underside are grayish white with white tips of hair and a light gray hairline. The undersides of the neck, hind paws, and tail are white. The color of the fur on the upper side becomes lighter and more yellow-tinged from north to south and south-east, the breast spot becomes paler and decreases in size.

Skull and teeth

The skull of Eversmann dwarf hamster has no obvious bone strips. Bone ridges over the eye socket and on the parietal bone are not present. The lower jaw is wider than that of the Mongolian dwarf hamster, the incisor holes do not extend back to the level of the first molar and the tympanic sacs are comparatively small.

The cusps of the second and third lower molars are only slightly offset from one another. At the base of the outer anterior tooth cusp, the first upper molar occasionally has an additional, small, tooth-shaped cusp that is nowhere near the height of the other tooth cusps.

genetics

According to Romanenko and co-workers, the karyotype of the Eversmann dwarf hamster with 26 chromosomes differs from the assumed original karyotype of the medium-sized dwarf hamster by three chromosome fusions. The number of chromosome arms is 40 or 38. The three subspecies differ by deletion in the short arm of the subtelocentric autosome 6. Since this consists of euchromatin , there is no quantitative difference in heterochromatin .

Way of life

The Eversmann dwarf hamster's predators are the short-eared owl and other owls as well as birds of prey , falcons and predators .

Habitat and population density

The natural habitat of the Eversmann dwarf hamster are dry steppes and semi-deserts and it inhabits rock and salt soils as well as semi-solid humpback sands . In the north of the range it penetrates forest areas , but avoids alluvial forests . A typical biotope is grass - wormwood - steppes. He also inhabits grassland , fields , agricultural wasteland , roadsides and other non-cultivated parts of fields as well as the surrounding area of settlements .

Its population density is usually low and stable. In the steppes of northern Kazakhstan, Karassewa found between 0.1 and 1.2 percent of the trapped rodents in various biotopes from 1954 to 1959 . Under favorable conditions, however, the density can increase quickly and so it reached up to 32 percent in grain fields . According to Shchepotjew, it occurs most frequently in maize and stubble fields , beet fields , woody trees , forest belts and other plantations . He found the highest proportion of trapped rodents in maize and stubble fields at 37.9 to 75.0 percent.

Diet, predators and parasites

The Eversmann dwarf hamster feeds on plant and animal food. It consumes the shoots and seeds of many wild and cultivated plants such as thistle , hair strand , wheat , rye and oats . After growing wheat in what were once large steppe areas, he quickly switched to this as the main food. Regular animal feed includes insects and mollusks, and it preyes on lizards , voles , chicks, small birds and young ground squirrels .

Its predators include owl , short-eared owl , Tawny Eagle , Imperial Eagle , Kestrel , Lesser Kestrel , Saker , Marsh Harrier , Pallid Harrier , Black Kite , red fox , ermine and polecats . A typical external parasite is the flea Amphipsylla kalabukhovi , which is also found on other dwarf hamsters and voles.

Eversmann's dwarf hamster's predators
Predator region Occurrence in lumps and excrement Share of total food Rank in nutrition Individual evidence
Eversmann dwarf hamster
Little owl Kazakhstan, Big and Small Irgis in Russia 0.8 percent - 9th to 10th place
Short-eared Owl Northern Kazakhstan 3.4 percent - -
0.5 percent - -
Steppe eagle Kazakhstan - - -
Imperial eagle Northern Kazakhstan - 1.9 percent -
Kazakhstan - - -
Kestrel Northern Kazakhstan 0.5 percent - -
Northern Kazakhstan 0.3 percent - -
Red hawk Northern Kazakhstan 0.5 percent - -
Sucker falcon Northern Kazakhstan - - -
Steppe consecration Kazakhstan 0.8 percent - -
Black kite Middle reaches of the Urals in Russia - 1.0 percent -
Aktobe in Kazakhstan sporadically
Red fox Atbassar in Kazakhstan - - -
Torghai region in Kazakhstan 0.7 percent - 8th to 10th place
Karagandy Territory in Kazakhstan - - -
Tussum in Kazakhstan 0.8 percent - -
Eversmann and gray dwarf hamsters
Red fox Aktobe in Kazakhstan 0.4 percent - 8th place
Volgograd Oblast in Russia - - -

Construction, activity and behavior

The self-dug construction of the Eversmann dwarf hamster is comparatively easy. The main tube is rarely deeper than 30 centimeters and runs straight or at an angle downwards. Two to three branches can branch off from the nest at the end of the tube. It can often be found in the burrows of other small mammals. In Kazakhstan, he lives in the dwarfs' burrows .

The Eversmann dwarf hamster hoards food for the winter in its burrow . At least in the south of the range it does not hibernate , but its activity is reduced in winter. It is mainly active at twilight and at night , solitary and aggressive towards other species .

Reproduction

The reproductive period of the Eversmann dwarf hamster begins in April to May and ends in August to September. In some parts of the range it also reproduces in winter. The number of litters per year is two to three in the north and three to four in the south of the range, with females born in the current year sometimes one or two in the north and two to three in the south. Usually four to six young animals are born per litter. In 39 captured females three times four, eleven times five, ten times six, twelve times seven, once eight and twice nine embryos or scars were found in the uterus.

Under favorable conditions, the Eversmann dwarf hamster can change from a previously rare species to a dominant one within two to three years as a result of a change in reproductive intensity. In northern Kazakhstan, Karassewa found a mean litter size of 5.6 to 6.2 young animals in fescue - feathergrass steppes and a mean litter size of 8.8 to 9.2 young animals in wheat fields.

Distribution and fossil finds

Eversmann dwarf hamster (Kazakhstan)
1859
1859
1925
1925
1932
1932
1934
1934
1969
1969
Type localities of the Eversmann dwarf hamster: 1859 eversmanni , 1925 microdon , 1932 beljaevi , 1934 belajevi and 1969 pseudocurtatus

The distribution area of the Eversmann dwarf hamster are the steppes and semi-deserts of northern Kazakhstan and neighboring Russia from the lower Volga to the Irtysh in the Saissan Basin . In the north it reaches up to Bugulma , Sterlitamak and Orsk , in the south of the Chelyabinsk region and to the Rajons Swerinogolowski on Tobol , Marjewka the Ishim and Aktogai the Irtysh. In the south it extends to the northern coast of the Caspian Sea , to the Embaer Ustyurt plateau , to the Aral-Karakum , to the middle of the hunger steppe , to the north of the Balkhash region and to the south of the Saissan Basin. The allocation of finds in the neighboring areas of Mongolia and Xinjiang in northwest China is controversial. Gromov and Jerbayeva consider this to be implausible. According to Wang, however, the north of Xinjiang is part of its distribution area. In the early twentieth century, the Eversmann dwarf hamster was widespread in the forests and steppes in front of and behind the Urals , and was found in small numbers in virtually all of the southern Urals.

Fossil finds of the Eversmann dwarf hamster or a presumably closely related, so far not described species come from early Pleistocene deposits far west of the Volga, from the Crimea in the south to the southern and central Don region and apparently to the Shiguli Mountains in the north.

Subspecies

Kartawzewa and Surow (2005) distinguish three subspecies of the Eversmann dwarf hamster:

  • Allocricetulus eversmanni eversmanni (Brandt, 1859) in the west of the distribution area with the subjective synonym microdon (Ognev, 1925) ,
  • Allocricetulus eversmanni beljaevi (Aryropulo, 1932) in the east of the distribution area with the objective synonyms beljawi (Argyropulo, 1933) and beljaevi (Kuznetzov, 1944) as well as the subjective synonym belajevi (Selevin, 1934) and
  • Allocricetulus eversmanni pseudocurtatus Vorontsov & Kryukova, 1969 in the east of the Saissan Basin .

Gromow and Baranowa (1981) name two or three subspecies. Gromow and Jerbajewa (1995) assume no more than two subspecies and combine pseudocurtatus with beljaevi .

Allocricetulus eversmanni eversmanni

The fur of Allocricetulus eversmanni eversmanni is colored monotonously dark brown and the breast spot is large and clear. The number of chromosome arms is 40. Eight autosomes are metacentric or submetacentric , of which two are large, two are medium and four are small. Four large autosomes are subtelocentric and twelve medium to small autosomes are acrocentric . The medium-sized X chromosome is submetacentric. The short arm of the large subtelocentric autosome 5 has no clear G bands , the short arm of the large subtelocentric autosome 6 has a clear G band in the pericentromere region, and the smallest acrocentric autosomes 11 and 12 do not have clear G bands. C bands indicate low levels of heterochromatin in two-armed autosomes 1, 2, 5, and 6. The small metacentric autosomes 3 and 4 and the small acrocentric autosomes 8 to 12 have heterochromatin in the pericentromere region. The X chromosome has a dark C-block in the pericentromere region of the short arm. Nucleolus organizer regions were detected in five pairs of autosomes. In the case of the two-armed autosomes 2, 4 and 5 these are located on the telomere , in the case of autosome 5 in the short arm. In acrocentric autosomes 8 and 10, they are located on the centromere .

The type specimen of the nominate form comes from the vicinity of Orenburg in the southern Russian oblast of the same name and is presumably in the Zoological Institute of the Russian Academy of Sciences . Named after Eduard Friedrich von Eversmann , Johann Friedrich von Brandt described this as Cricetus eversmanni in 1859 . Another specimen from Ponomarjowka near Buguruslan in the northwest of Orenburg Oblast was described by Sergei Iwanowitsch Ognew in 1925 as Mesocricetus microdon and thus assigned to the middle hamsters . It is located in the Zoological Museum of Moscow State University . The species epithet microdon derives from ancient Greek micros (μικρος, "small") and odon (οδον, "tooth") from.

Allocricetulus eversmanni beljaevi

The fur of Allocricetulus eversmanni beljaevi is rust-brown-sand-colored and the breast spot is small and pale. The number of chromosome arms is 40. Eight autosomes are metacentric , ten telocentric and six subtelocentric . The X chromosome and Y chromosome are submetacentric .

The type specimen comes from the coast of Lake Saissan in eastern Kazakhstan and is located in the Zoological Institute of the Russian Academy of Sciences . AI Argiropulo described this in 1932 as Cricetulus (Allocricetulus) eversmanni beljaevi . Another specimen from the Aktogai district to the right of the Tokrau is also in the Zoological Institute and was described by WA Selewin in 1934 as Cricetulus eversmanni belajevi . According to Musser and Carleton, the subspecies was described by Argiropulo as beljawi in 1933 and the name beljaevi was first used by BA Kuznetsov in 1944 .

Allocricetulus eversmanni pseudocurtatus

Allocricetulus eversmanni pseudocurtatus does not differ externally from Allocricetulus eversmanni beljaevi . However, the number of chromosome arms is only 38. Eight autosomes are metacentric , twelve telocentric and four subtelocentric . The X chromosome is metacentric or submetacentric and the Y chromosome is submetacentric or subtelocentric. According to Kartavzewa and Voronzow, autosome 5 differs in shape and the Y chromosome in size and shape from those of the other subspecies.

The type specimen comes from the east of the Saissan Basin in eastern Kazakhstan and is presumably in the Zoological Institute of the Russian Academy of Sciences . Nikolai Nikolajewitsch Voronzow and JP Krjukowa described this in 1969 as Allocricetulus eversmanni beljaevi pseudocurtatus . Vorontsov does not consider a status as an independent species to be justifiable. Musser and Carleton give the name as a noun nudum . It is derived from ancient Greek pseudos (ψευδος, "deception") and the specific epithet curtatus of the Mongolian dwarf hamster.

Eversmann dwarf hamster and human

In Siberia, the distribution area of ​​the Eversmann dwarf hamster in human settlements extends further north than its original distribution area. It can be found in rural buildings and dwellings such as yurts and temporarily abandoned Kazakh winter camps. It causes considerable damage in the grain industry . Its relevance to epidemics has not been adequately researched. In addition to soil and climatic conditions, a lack of suitable biotopes in the peripheral areas and the use of inorganic fertilizers are mentioned as possible risks for the population. In the middle of the twentieth century it was still common in the steppes of Chelyabinsk Oblast , but it is now rare there. It is protected at the Arkaim archaeological site .

More recent information on the Eversmann dwarf hamster is not available and Nechay recommends investigations in the natural habitat and in the cultivated landscape . "Eversmann dwarf hamster" is used as a common German name (Flint, 1966; Piechocki, 1969; Grzimek, 1988).

supporting documents

literature

  • Wladimir Evgenjewitsch Flint: The dwarf hamsters of the Palearctic fauna . In: The New Brehm Library . 2nd Edition. tape 366 . Westarp Wissenschaften, Hohenwarsleben 2006, ISBN 3-89432-766-9 (first edition: 1966, German, reprint of the 1st edition from 1966, 99 pages).
  • Igor Michailowitsch Gromow, Margarita Alexandrovna Jerbajewa: [The mammals of Russia and adjacent territories. Lagomorphs and Rodents] . Russian Academy of Sciences (Zoological Institute), Saint Petersburg 1995 ( full text - original Russian title: Mljekopitaiuschtschije fauny Rossii i soprjedjelynch tjerritorij. Saizeobrasnyje i grysuny , 520 pages).
  • Irina Wassiljewna Kartawzewa, Alexei Wassiljewitsch Surow: G-, C-, and NOR-stained Karyotype of the Eversmann's Hamster Allocricetulus eversmanni and comparison with the karyotype of Cricetulus species (Rodentia: Cricetinae) . In: Mammal Study . tape 30 , no. 1 , 2005, ISSN  1343-4152 , p. 89–91 (English, full text ).
  • NW Kisselewa, NL Pogodin: [Eversmann dwarf hamster] . In: WD Sakharov, NS Korytin (ed.): [Red Book of Chelyabinsk Oblast: Animals, Plants, Mushrooms] . Yekaterinburg 2005 ( full text - original Russian title: Chomjatschok ewjersmanna , original title of the collective work: Krasnaja Kniga Tscheljabinskoi oblasti: schiwotnyje, rastenija, griby , 450 pages).
  • 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 (English, full text ).
  • Gábor Nechay: Status of Hamsters: Cricetus cricetus , Cricetus migratorius , Mesocricetus newtoni and Other Hamster Species in Europe . In: Nature and Environment Series . No. 106 , p. 1–74 (English, full text ( Memento from November 21, 2010 in the Internet Archive ) [PDF]).
  • Andrew T. Smith, Robert S. Hoffmann: Subfamily Cricetinae . 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. 239-247 (English).

Individual evidence

  1. ↑ a b c Musser and Carleton, 2005 (" Allocricetulus eversmanni ( Memento of the original from June 6, 2010 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove it Note. "Pp. 1040-1041). @1@ 2Template: Webachiv / IABot / www.bucknell.edu
  2. ↑ Jonathan EM Baillie: Allocricetulus eversmanni . In: IUCN 2007 (Ed.): 2007 IUCN Red List of Threatened Species . 1996 (English).
  3. ↑ Musser and Carleton, 2005 (" Allocricetulus curtatus ( Memento of the original dated June 6, 2010 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this note. " P. 1040). @1@ 2Template: Webachiv / IABot / www.bucknell.edu
  4. ↑ a b c d e f Smith and Hoffmann, 2008 (“ Allocricetulus eversmanni ” pp. 240–241).
  5. ↑ a b c Flint, 1966 (“Systematics, Descriptions, Distribution” p. 11).
  6. ^ Robert Matthey: Chromosomes, hétêrochromosomes et cytologie comparée des Cricetinae Paléarctiques (Rodentia) . In: Caryologia . tape 13 , no. 1 , 1960, ISSN  0008-7114 , pp. 199-223 (French). Quoted in: Flint, 1966 (“Systematics, Descriptions, Distribution” p. 12).
  7. ^ Igor Jakowlewitsch Pawlinow: Mlekopitaiuschtschije Rossii ( Memento of July 10, 2010 in the Internet Archive ) .
  8. ↑ a b c d e f g h i j k l m n o Gromov and Jerbajewa, 1995 ( " Allocricetulus eversmanni ").
  9. ↑ Svetlana Anatoljewna Romanenko u. a .: Karyotype Evolution and Phylogenetic Relationships of Hamsters (Cricetidae, Muroidea, Rodentia) Inferred from Chromosomal Painting and Banding Comparison . In: Chromosome Research . tape 15 , no. 3 , 2007, ISSN  0967-3849 , p. 283–297 , doi : 10.1007 / s10577-007-1124-3 (English, Tab. 1, Fig. 6).
  10. ↑ a b c d e Kartawzewa and Surow, 2005 (pp. 89–90).
  11. ↑ Flint, 1966 (“Biotopes and Settlements” Fig. 26).
  12. ↑ a b Nechay, 2000 (pp. 54-55).
  13. ↑ Evgenija Wassiljewna Karassewa: [Materials for knowledge of the geographic distribution and biology of some species of small mammals in northern and central Kazakhstan] . In: Trudy Moskowskowo obschtschestwa ispytatelei prirody, biologija, biogeografija i sistematika mljekopitaiuschtschich SSSR . tape 10 , 1963 (Russian). Quoted in: Flint, 1966 (“Populationsdynamik” pp. 37-38).
  14. ^ NW Shchepotjew: [An Outline of the Distribution and Stational Location of Some Muriform Rodents in the Lower Volga Region] . In: Fauna and Ecology of Rodents . tape 12 . Publishing house of the Moscow State University, Moscow 1975, p. 62–97 (Russian, abstract in English). Quoted in: Nechay, 2000 (p. 54).
  15. ↑ Je. S. Danini, NA Olschwang: [Comments on the anatomy and biology of the Eversmann dwarf hamster] . In: [Materials on the ecology and biology of rodents of the Troitsk district in the former Ural region] . tape 10 . Publishing house of the Perm State University, Perm 1936 (Russian). Quoted in: Kisselewa and Pogodin, 2005.
  16. ↑ a b Karassewa, 1963. Quoted in: Flint, 1966 (“Vermehrung” p. 46).
  17. ↑ Flint, 1966 ("Mortality" pp. 50–56).
  18. ↑ a b c d Kisselewa and Pogodin, 2005.
  19. ↑ Flint, 1966 ("Parasiten" p. 81).
  20. ↑ a b c d e f g h W. I. Osmolowskaja: [The geographical distribution of the birds of prey in the plains of Kazakhstan and their importance for the decimation of the pests] . In: Trudy instituta geografii Akademii Nauk SSSR . No. 54 , 1953 (Russian). Quoted in: Flint, 1966 (“Mortality” pp. 50–56).
  21. ^ A b I. F. Voloshin: [Observations on Marsh Harriers, Imperial Eagles and Peregrine Falcons in Northern Kazakhstan] . In: Trudy Naursumsk. Goss. Sapowednik . No. 2 , 1949 (Russian). Quoted in: Flint, 1966 (“Mortality” pp. 50–56).
  22. ↑ LA Gibet: [On the ecology of the birds of prey in the forest islands of northern Kazakhstan] . In: Utsch. sap. Mosk. Goss. Univ. 189 (biogeography), 1959 (Russian). Quoted in: Flint, 1966 (“Mortality” pp. 50–56).
  23. ↑ AA Samorodow: [On the ecology of the black kite Milvus korschun (Gm.)] . In: Bjulleten Moskowskowo obschtschestwa ispytatelei prirody, otdel biologitscheski . tape 44 , no. 4 , 1935 (Russian). Quoted in: Flint, 1966 (“Mortality” pp. 50–56).
  24. ↑ SN Warschawski: [Particularities in the diet of the black kite in the Aktyubinsk steppe] . In: Ornitologija . tape 6 , 1963, pp. 210-215 . Quoted in: Urs N. Glutz von Blotzheim, Kurt M. Bauer, Einhard Bezzel: Milvus migrans  - Schwarzmilan . In: Urs N. Glutz von Blotzheim (Hrsg.): Handbook of the birds of Central Europe. Volume 4: Falconiformes. Birds of prey . 2nd Edition. Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , p. 97-136 (German; p. 135).
  25. ↑ a b Alexander Nikolajewitsch Formosow, WI Osmolowskaja: [On the ecology of the fox in the steppe and desert zone of the USSR] . In: Trudy Moskowskowo obschtschestwa ispytatelei prirody, biologija, biogeografija i sistematika mljekopitaiuschtschich SSSR . tape 10 , 1963 (Russian). Quoted in: Flint, 1966 (“Mortality” pp. 50–56).
  26. ↑ Flint, 1966 ("Build" Fig. 48).
  27. ↑ Flint, 1966 ("Vermehrung" p. 41).
  28. ↑ Flint, 1966 ("Vermehrung" p. 44).
  29. ↑ Wang Ying-Xiang: A Complete Checklist of Mammal Species and Subspecies in China. A Taxonomic and Geographic Reference . China Forestry Publishing House, Beijing 2003 (394 pages). Quoted in: Musser and Carleton, 2005 (“ Allocricetulus eversmanni ( Memento of the original from June 6, 2010 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this note . "Pp. 1040-1041). @1@ 2Template: Webachiv / IABot / www.bucknell.edu
  30. ^ Igor Michailowitsch Gromow, GI Baranowa (ed.): [Catalog of Mammals of the USSR. Pliocene to Our Age] . Verlag Nauka, Sankt Petersburg 1981 (Russian original title: Catalog mlekopitaiuschtschich SSSR. Pliozen-sowremennost , 456 pages). Quoted in: Nechay, 2000 (p. 54).
  31. ^ A b c Igor Jakowlewitsch Pawlinow, Olga Leonidowna Rossolimo: [Systematics of Mammals of USSR] . Publishing house of the Moscow State University, Moscow 1987 ( full text - original Russian title: Sistematika mlekopitaiuschtschich SSSR , 285 pages).
  32. ↑ Irina Wassiljewna Kartawzewa, Nikolai Nikolajewitsch Voronzow: Chromosome Differences Among Subspecies of Hamster Allocricetulus eversmanni (Rodentia, Cricetidae) and the New Taxon of Subspecific Rank Description . In: Chromosome Information Service . tape 53 , 1992, pp. 8-10 (English). Quoted in: Kartawzewa and Surow, 2005 (p. 89).
  33. ↑ Boris Stepanowitsch Winogradow, Igor Michailowitsch Gromow: The rodents of the fauna of the USSR . Moscow / St. Petersburg 1952, p. 156-213 (Russian). Quoted in: Nechay, 2000 (p. 55).
  34. ↑ Flint, 1966 ("Synanthropismus" pp. 75-77).
  35. ^ Rudolf Piechocki: Family Wühler . In: Irenäus Eibl-Eibesfeldt, Martin Eisentraut, Hans-Albrecht Freye, Bernhard Grzimek, Heini Hediger, Dietrich Heinemann, Helmut Hemmer, Adriaan Kortlandt, Hans Krieg, Erna Mohr, Rudolf Piechocki, Urs Rahm, Everard J. Slijper, Erich Thenius ( Ed.): Grzimeks Tierleben : Encyclopedia of the Animal Kingdom. Eleventh volume: Mammals 2 . Kindler-Verlag, Zurich 1969, p. 301-344 (German; p. 307, p. 517).
  36. ↑ Bernhard Grzimek: Systematic overview of the mammals . In: Bernhard Grzimek (Ed.): Grzimek's Encyclopedia of Mammals. Volume 11 . 1988, p. 11–55 (German, eleven-volume licensed edition of the original edition from 1988; p. 34).