The Mexican spiny pocket mouse (''Heteromys irroratus'') 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 na ...

in the family

Heteromyidae Heteromyidae is a family of rodents consisting of kangaroo rats, kangaroo mice, pocket mice and spiny pocket mice. Most heteromyids live in complex burrows within the deserts and grasslands of western North America, though species within the gen ...

. It is native to Mexico and

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

in the United States where it is found in dry, scrubby habitats. The

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

has assessed it as being of "

least concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...

". It was formerly placed in the genus ''Liomys'', which is now recognized to be

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

and has been subsumed into ''

Heteromys ''Heteromys'' is a genus of rodents in the family Heteromyidae, commonly known as spiny pocket mice. It is the only extant genus in the subfamily Heteromyinae which also includes the extinct genera ''Diprionomys'' and ''Metaliomys''. ''Heteromys ...

''.

Description

There are seven

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

of Mexican spiny pocket mouse and there is considerable differences in color and size between different populations. In general it is a medium-sized member of its genus ''

'', growing to a head and body length of about with a tail of about the same length. The

pelage Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily #Guard hair, guard hair on top and thick #Down hair, underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as ...

is composed of a mixture of stiff spines with soft hairs, but because the hairs lie flat, the spines are the more noticeable part of the coat. The upper parts of the head and body are greyish-brown and the underparts whitish. There is a pinkish or buff lateral line separating the two colors. Juveniles are grey and initially lack spines which grow through the coat later. The soles of the feet are haired and the Mexican spiny pocket mouse is unique in its genus in possessing five rather than six tubercles on the hind foot.

Distribution and habitat

The Mexican spiny pocket mouse is

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 elsew ...

to parts of Texas and Mexico. Its range extends from just north of the

Rio Grande The Rio Grande ( and ), known in Mexico as the Río Bravo del Norte or simply the Río Bravo, is one of the principal rivers (along with the Colorado River) in the southwestern United States and in northern Mexico. The length of the Rio G ...

southwards to the

Mexican Plateau The Central Mexican Plateau, also known as the Mexican Altiplano ( es, Altiplanicie Mexicana), is a large arid-to-semiarid plateau that occupies much of northern and central Mexico. Averaging above sea level, it extends from the US-Mexico border ...

, its southernmost limit being Zapotitlán in the state of

Oaxaca Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...

. It is found in dry shrubland at altitudes of up to . In regions where their ranges overlap, it occurs in drier, upland habitats than the

painted spiny pocket mouse The painted spiny pocket mouse (''Heteromys pictus'') is a species of rodent in the family Heteromyidae. It is found in Mexico and the northern tip of Guatemala. It was formerly placed in the genus ''Liomys'', which is now recognized to be paraph ...

(''Liomys pictus''). It is not normally present in areas with less than of annual rainfall.

Parasites

The Mexican spiny pocket mouse is parasitized by the mouse botfly, ''

Cuterebra fontinella ''Cuterebra fontinella'', the mouse bot fly, is a species of New World skin bot fly in the family Oestridae. ''C. fontinella'' is typically around in length with a black and yellow color pattern. ''C. fontinella'' develops by parasitizing nutrien ...

''.

Behavior

Four different methods of locomotion are used by the Mexican spiny pocket mouse. The fastest is a kangaroo-like leaping gait, during which the mouse can cover 1.5 metres (5 feet) in a second. This pocket mouse is

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

and spends the day in a burrow, the entrance of which may be covered with leaves or an earth mound. The diet consists largely of seeds, particularly of hackberry (''Celtis'' sp.),

mesquite Mesquite is a common name for several plants in the genus ''Prosopis'', which contains over 40 species of small leguminous trees. They are native to dry areas in the Americas. They have extremely long roots to seek water from very far under grou ...

and other trees and shrubs. These are stored in

cheek pouch Cheek pouches are pockets on both sides of the head of some mammals between the jaw and the cheek. They can be found on mammals including the platypus, some rodents, and most monkeys, as well as the marsupial koala. The cheek pouches of chipmunks ...

es and carried back to the burrow. In laboratory studies it was found that this pocket mouse was unable to maintain its body weight unless it had access to water. Reproduction takes place during much of the year but seems to peak between August and November. Litter sizes range from two to eight with four young being typical.

Status

The Mexican spiny pocket mouse has a wide range and is common in suitable habitats within that range. The population size seems to be stable and no particular threats have been identified so the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

lists its conservation status as being of "

References

{{Taxonbar, from=Q115792

Mexican Spiny Pocket Mouse The Mexican spiny pocket mouse (''Heteromys irroratus'') is a species of rodent in the family Heteromyidae. It is native to Mexico and Texas in the United States where it is found in dry, scrubby habitats. The IUCN has assessed it as being of "le ...

Rodents of North America Fauna of the Rio Grande valleys Mammals of Mexico Mammals of the United States Least concern biota of Mexico Least concern biota of the United States Mammals described in 1868 Taxonomy articles created by Polbot