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Temporal range: Late Pleistocene to Recent
Tokudaia spp. - National Museum of Nature and Science, Tokyo - DSC07082.JPG
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Muridae
Tribe: Apodemini
Genus: Tokudaia
Kuroda, 1943
Type species
Rattus jerdoini osimensis [1]

See text

Tokudaia is a genus of murine rodent native to Japan. [1] Known as Ryūkyū spiny rats or spinous country-rats, population groups exist on several non-contiguous islands. [2] Despite differences in name and appearance, they are the closest living relatives of the Eurasian field mouse ( Apodemus ). Of the three species, both T. osimensis and T. tokunoshimensis have lost their Y chromosome and SRY gene; the sex chromosomes of T. muenninki, on the other hand, are abnormally large. [3]


Named species are: [3]

At least Tokudaia osimensis may be a cryptic species complex.

See also

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  1. 1 2 Musser, G.G.; Carleton, M.D. (2005). "Genus Tokudaia". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. pp. 1512–1513. ISBN   978-0-8018-8221-0. OCLC   62265494.
  2. Mammalian Genome article
  3. 1 2 Murata, C.; Yamada, F.; Kawauchi, N.; Matsuda, Y.; Kuroiwa, A. (2011-12-24). "The Y chromosome of the Okinawa spiny rat, Tokudaia muenninki, was rescued through fusion with an autosome". Chromosome Research. 20: 111–125. doi: 10.1007/s10577-011-9268-6 .

Wikispecies-logo.svg Data related to Tokudaia at Wikispecies