Red viscacha rat

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Red viscacha rat
Tympanoctomys barrerae

Tympanoctomys barrerae

Systematics
Subordination : Porcupine relatives (Hystricomorpha)
Partial order : Hystricognathi
without rank: Guinea Pig Relatives (Caviomorpha)
Family : Trug rats (Octodontidae)
Genre : Tympanoctomys
Type : Red viscacha rat
Scientific name
Tympanoctomys barrerae
( Lawrence , 1941)

The red viscacha rat ( Tympanoctomys barrerae ) is a species of rodent that lives in South America and belongs to the family of Trug rats (Octodontidae).

features

Outwardly, red viscacha rats are rat-like animals. They reach a head body length of around 12 centimeters, the tail is around 14 centimeters long, the weight is around 80 grams. Their fur is reddish-brown in color, the underside is slightly lighter, the feet are white. The skull is characterized by the greatly enlarged tympanic bulla (a bony, blister-like structure in the area of ​​the temporal bone ), which makes the head appear greatly enlarged.

What is remarkable about this animal is that it was the first known tetraploid mammal, that is, had four sets of chromosomes instead of the usual two. The species is said to have originated from hybridization of two closely related species 6.5 million years ago. The karyotype is 4n = 102. In the meantime, a similar chromosome structure has also been found in the newly discovered golden viscacha rat.

distribution and habitat

Red viscacha rats are endemic to Argentina , where they inhabit arid plains in the province of Mendoza and possibly adjacent areas of the province of La Pampa .

Way of life

Very little is known about the way these animals live. They only occur in places with salt plants (halophytes) and are pure herbivores that feed primarily on leaves and stalks.

Due to its small distribution area and the assumed decline in populations, the species is listed by the IUCN in the warning list ( near threatened ).

literature

  • Ronald M. Nowak: Walker's Mammals of the World. 2 volumes. 6th edition. Johns Hopkins University Press, Baltimore MD et al. 1999, ISBN 0-8018-5789-9 .
  • 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 .

Individual evidence

  1. Milton H. Gallardo, CA Gonzalez, I. Cebrian: Molecular cytogenetics and allotetraploidy in the red vizcacha rat, Tympanoctomys barrerae (Rodentia, Octodontidae). In: Genomics. Vol. 88, No. 2, August 2006, ISSN  0888-7543 , pp. 214-221, doi : 10.1016 / j.ygeno.2006.02.010 .
  2. Milton H. Gallardo, G. Kausel, A. Jiménez, C. Bacquet, C. González, J. Figueroa, N. Köhler, R. Ojeda: Whole-genome duplications in South American desert rodents (Octodontidae). In: Biological Journal of the Linnean Society. Vol. 82, No. 4, August 2004, ISSN  0024-4066 , pp. 443-451, doi : 10.1111 / j.1095-8312.2004.00331.x .
  3. Tympanoctomys barrerae in the Red List of Threatened Species of the IUCN 2010. Posted by: Lessa, E., Ojeda, R. & Bidau, C., 2008. Accessed on December 18 of 2010.