Plains Viscacha Rat

Plains Viscacha Rat
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Octodontidae
Genus: Tympanoctomys
Yepes, 1942
Species: T. barrerae
Binomial name
Tympanoctomys barrerae
(B. Lawrence, 1941)[2]

The Plains Viscacha Rat or Red Vizcacha Rat (Tympanoctomys barrerae) is a species of rodent in the family Octodontidae. It is monotypic within the genus Tympanoctomys.[3] It is endemic to central western Argentina, where it has a fragmented range.[1] Its natural habitat is desert scrubland, dunes and salt flats, where it eats halophyte plants.[1] It is a solitary, nocturnal rodent that constructs large mounds with complex burrows.[1][4] This species of rodent is unusual because it is tetraploid (4x = 2n = 102). Scientists think that this species may have arisen when an ancestor (very possibly the Mountain Vizcacha Rat, Octomys mimax, chromosome count 2x = 2n = 56) doubled its chromosome number, presumably by errors in mitosis or meiosis within the animal's reproductive organs.[5] Research has found another closely related species Pipanacoctomys aureus which is also tetraploid and appears to be the sister species of T. barrerae.[6]

The species is threatened by destruction of its fragmented and restricted habitat.[1]

References

  1. ^ a b c d e Lessa, E., Ojeda, R. & Bidau, C. (2008). Tympanoctomys barrerae. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 5 January 2009.
  2. ^ Lawrence, B. (1941), "A new species of Octomys from Argentina", Proceedings of the New England Zoological Club 18: 43–46. 
  3. ^ Woods, Charles A.; Kilpatrick, C. William (16 November 2005). "Infraorder Hystricognathi (pp. 1538-1600)". In Wilson, Don E., and Reeder, DeeAnn M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). pp. 1573. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=13400390. 
  4. ^ Mares, Michael A. (1 November 2003), "Desert dreams: seeking the secret mammals of the salt pans - Naturalist at Large", Natural History, http://findarticles.com/p/articles/mi_m1134/is_9_112/ai_110737005/ 
  5. ^ Gallardo, M.H.; González, CA; Cebrián, I (2006), "Molecular cytogenetics and allotetraploidy in the red vizcacha rat, Tympanoctomys barrerae (Rodentia, Octodontidae)", Genomics 88 (2): 214–221, August 2006, doi:10.1016/j.ygeno.2006.02.010, PMID 16580173, http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WG1-4JKYTJP-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a18e9e7ecd4f6082c8579d751043661d, retrieved 2008-07-16 
  6. ^ Gallardo, M.H.; Kausel, G.; Jiménez, A.; Bacquet, C.; González, C.; Figueroa, J.; Köhler, N.; Ojeda, R. (2004), "Whole-genome duplications in South American desert rodents (Octodontidae)", Biological Journal of the Linnean Society 82 (4): 443–451, doi:10.1111/j.1095-8312.2004.00331.x.