Aegialomys galapagoensis, also known as the Galápagos Rice Rat or Galápagos Oryzomys, is a species of rodent

Rodent

Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

 in the family Cricetidae

Cricetidae

The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, and New World rats and mice...

 from the Galápagos Islands

Galápagos Islands

The Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...

. It belongs to the genus Aegialomys

Aegialomys

Aegialomys is a genus of oryzomyine rodents from the lowlands and mountains of western Peru and Ecuador, including the Galápagos Islands. The species in this genus have historically been placed in Oryzomys, but according to cladistic research, the genus is more closely related to a group...

in tribe Oryzomyini

Oryzomyini

Oryzomyini is a tribe of rodents in the subfamily Sigmodontinae of family Cricetidae. It includes about 120 species in about thirty genera, distributed from the eastern United States to the southernmost parts of South America, including many offshore islands...

, but was previously placed in Oryzomys

Oryzomys

Oryzomys is a genus of semiaquatic rodents in the tribe Oryzomyini living in southern North America and far northern South America. It includes eight species, two of which—the marsh rice rat of the United States and O. couesi of Mexico and Central America—are widespread; the six others have...

as Oryzomys galapagoensis. Its natural habitat

Habitat

* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 is subtropical or tropical dry shrubland

Shrubland

Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...

. Like many of the animals of the Galápagos, it is tame and unafraid of humans. Scientists working on Santa Fé Island

Santa Fe Island

Santa Fe Island , also called Barrington Island after admiral Samuel Barrington, is a small island of 24 km² which lies in the centre of the Galapagos archipelago, to the south east of Santa Cruz Island. Geologically it is one of the oldest, since volcanic rocks of about 4 million years old...

 and Fernandina Island

Fernandina Island

Fernandina Island is the third largest, and youngest, island of the Galápagos Islands. Like the others, the island was formed by the Galápagos hotspot...

 have reported that it is necessary to keep tents open to prevent these rice rats from chewing in during the night. The subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 A. g. bauri from Santa Fé Island is sometimes considered to represent a full species. A. g. galapagoensis was formerly found on San Cristóbal Island

San Cristóbal Island

San Cristóbal is the easternmost island in the Galápagos archipelago, and one of the oldest geologically.Its Spanish name "San Cristóbal" comes from the patron saint of seafarers, St. Christopher...

, where Charles Darwin

Charles Darwin

Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...

 captured several live specimens on the second voyage of HMS Beagle

Second voyage of HMS Beagle

The second voyage of HMS Beagle, from 27 December 1831 to 2 October 1836, was the second survey expedition of HMS Beagle, under captain Robert FitzRoy who had taken over command of the ship on its first voyage after her previous captain committed suicide...

 in 1855. However, it is believed that it became extinct only decades after Darwin's visit, and the next specimens collected were subfossil remains found in lava tubes by David Steadman

David Steadman

David William Steadman is the curator of ornithology at the Florida Museum of Natural History at the University of Florida.His research has concentrated on the evolution, biogeography, conservation, and extinction of tropical birds, particularly in the islands of the Pacific Ocean. He has also...

 and colleagues in 1984. Its closest relative is Aegialomys xanthaeolus, the only other species in the genus, which is found in coastal Ecuador and Peru.

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. ISBN 978-0-8018-8221-0
• Tirira, D., Boada, C. and Weksler, M. 2008. . In IUCN. IUCN Red List of Threatened Species. Version 2009.2. <www.iucnredlist.org>. Downloaded on December 3, 2009.
• Steadman, David W.
  David Steadman
  David William Steadman is the curator of ornithology at the Florida Museum of Natural History at the University of Florida.His research has concentrated on the evolution, biogeography, conservation, and extinction of tropical birds, particularly in the islands of the Pacific Ocean. He has also...
  
  , Zousmer, Steven, Steadman, Lee M. 1988. Galápagos: Discovery on Darwin's Islands Washington: Smithsonian Institution Press ISBN 0-87474-882-8
• Weksler, M., Percequillo, A.R. and Voss, R.S. 2006. Ten new genera of oryzomyine rodents (Cricetidae: Sigmodontinae). American Museum Novitates 3537:1–29.