The Magdalena rat (''Xenomys nelsoni'') is a species of

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 Mandible, lower jaws. About 40% of all mammal specie ...

in the 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 over 870 species, it is either the largest or second-largest family ...

which is found only in a small region of western

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. It is the only species in the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Xenomys''. The common name comes from the village where the first specimen was collected, and the second part of the scientific name refers to the collector.

Description

The Magdalena rat is a relatively large member of its family, measuring in length, including the tail. Adults weigh an average of . The general body colour is cinnamon to yellowish brown, being paler on the head and fading to creamy white on the underparts. It can be distinguished from other local rat-like species by the presence of white spots above the eyes and behind the ears; the cheeks are also marked with white fur. The tail is both hairy and scaly, and is dark brown in colour.

Distribution and habitat

The species is

endemic Endemism is the state of a species being found only 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 foun ...

Colima Colima, officially the Free and Sovereign State of Colima, is among the 31 states that make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima. Colima is a small state of western Mexico on the cen ...

and southwest

Jalisco Jalisco, officially the Free and Sovereign State of Jalisco, is one of the 31 states which, along with Mexico City, comprise the 32 Political divisions of Mexico, Federal Entities of Mexico. It is located in western Mexico and is bordered by s ...

, along the Pacific coast of

. It is estimated to inhabit an area of no more than . Within this region, it is found in dense tropical forests at elevations up to . There are no recognised subspecies.

Biology and behaviour

The species is

arboreal Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The hab ...

and

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

. They use branches and vines in dense vegetation to travel from tree to tree, and mostly remain between above the ground. They spend the day sleeping in spherical nests constructed in tree hollows. The nests are lined with grass and

kapok Kapok fibre is a cotton-like plant fibre obtained from the seed pods of a number of trees in the Malvaceae family, which is used for stuffing mattresses and pillows, for padding and cushioning, and as insulation. Kapok may also refer to: Plants ...

fruit fibres. They also use specific

latrine A latrine is a toilet or an even simpler facility that is used as a toilet within a sanitation system. For example, it can be a communal trench in the earth in a camp to be used as emergency sanitation, a hole in the ground ( pit latrine), or ...

s, either in tree hollows or at the forks of branches. They breed between late May and November, and give birth to one or two young at a time. An

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

, it is threatened by

habitat destruction Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

and fragmentation due to

deforestation Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...

and development. It is known from only three localities, and is believed to have a very low, and declining, population.

References

{{Taxonbar, from=Q1550989 Neotominae Endemic mammals of Mexico Mammals described in 1892 Taxonomy articles created by Polbot Jalisco dry forests