The Ryukyu spiny rat (''Tokudaia osimensis'') is a species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...

in the family Muridae.

Endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

Amami Ōshima , also known as Amami, is the largest island in the Amami archipelago between Kyūshū and Okinawa. It is one of the Satsunan Islands. The island, 712.35 km2 in area, has a population of approximately 73,000 people. Administratively it is ...

island in the

Amami Islands The The name ''Amami-guntō'' was standardized on February 15, 2010. Prior to that, another name, ''Amami shotō'' (奄美諸島), was also used. is an archipelago in the Satsunan Islands, which is part of the Ryukyu Islands, and is southwest of ...

of the

Ryukyu archipelago The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Geography of Taiwan, Taiwan: the Ōsumi Islands, Ōsumi, Tokara Islands, Tokara, Amami Islands, Amami, Okinawa Islands, Okinawa, and Sakis ...

of Japan, its natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

is subtropical moist broadleaf forest. The karyotype has an odd diploid number, 2n = 25. Like its relative '' T. tokunoshimensis'', it has lost its

Y chromosome The Y chromosome is one of two sex chromosomes (allosomes) in therian mammals, including humans, and many other animals. The other is the X chromosome. Y is normally the sex-determining chromosome in many species, since it is the presence or abse ...

and ''SRY'' gene. The species is threatened by

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

and fragmentation,

predation Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

feral cat A feral cat or a stray cat is an unowned domestic cat (''Felis catus'') that lives outdoors and avoids human contact: it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens ...

s and dogs and introduced

mongooses A mongoose is a small terrestrial carnivorous mammal belonging to the family Herpestidae. This family is currently split into two subfamilies, the Herpestinae and the Mungotinae. The Herpestinae comprises 23 living species that are native to ...

, and competition with introduced black rats.

References

Y-chromosome - Will it or will it not, hold on?
Rats of Asia Endemic mammals of Japan Endemic fauna of the Ryukyu Islands Endangered fauna of Asia Tokudaia Mammals described in 1934 Taxonomy articles created by Polbot {{Murinae-stub

See also

References