''Nesoryzomys indefessus'', also known as the Santa Cruz nesoryzomys or Indefatigable Galápagos mouse,Duff and Lawson, 2004 is a

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), 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 roden ...

of the genus ''

Nesoryzomys ''Nesoryzomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae, endemic to the Galápagos Islands. Five species have been described, with two of them considered extinct Extinction is the termination of a kind of organism ...

'' of family

Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New World rats and mice. At almost 608 species, it is the second-largest family of mammals, a ...

from

Galápagos Islands The Galápagos Islands ( es, Islas Galápagos) are an archipelago of volcanic islands in the Eastern Pacific, located around the Equator west of the mainland of South America. They form the Galápagos Province of the Republic of Ecuador, with ...

Ecuador Ecuador ( ; ; Quechuan languages, Quechua: ''Ikwayur''; Shuar language, Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechuan ...

. It formerly lived on

Santa Cruz Island Santa Cruz Island ( Spanish: ''Isla Santa Cruz'', Chumash: ''Limuw'') is located off the southwestern coast of Ventura, California, United States. It is the largest island in California and largest of the eight islands in the Channel Islands ...

, but is now extinct, probably due to the introduction of

black rat The black rat (''Rattus rattus''), also known as the roof rat, ship rat, or house rat, is a common long-tailed rodent of the stereotypical rat genus ''Rattus'', in the subfamily Murinae. It likely originated in the Indian subcontinent, but is n ...

s. Another related rodent, '' N. narboroughi'', is sometimes considered to be a subspecies of ''N. indefessus''.

Etymology

Its

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

is Latin for "unwearied, indefatigable", but the species was named after its island, which was formerly known as "Indefatigable Island" after a ship with the same name.

References

Literature cited

*Musser, G.G. and Carleton, M.D. 2005. Superfamily Muroidea. Pp. 894–1531 in Wilson, D.E. and Reeder, D.M. (eds.)
Mammal Species of the World: a taxonomic and geographic reference. 3rd ed
Baltimore: The Johns Hopkins University Press, 2 vols., 2142 pp. Nesoryzomys Extinct rodents Extinct mammals of South America Endemic fauna of the Galápagos Islands Rodent extinctions since 1500 Taxa named by Oldfield Thomas Species made extinct by human activities Mammals described in 1899 {{Sigmodontinae-stub