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MammalingSpecies accountsRodents › Cricetidae

Long-nosed Rice Rat

Casiomys rostratus
LC · Least concern Rodentia Cricetidae
Size
8-10 cm + tail 9-12 cm
Weight
20 to 35 g
Activity
Nocturnal
Sociability
Solitary

Description

It is distinguished from the rest of Mesoamerican rice mice from its group by a notably lengthy and sharp fox, a trait that gives it a name and that is probably related to its particular form of forage between the leaves of the sotobosque. It lives in the tropical wet rainforest of a strain that goes from southern Mexico to northern South America, and as the rest of species of the so-called "alfaroi group" was moved in 2024 to a genus after a genetic and morphological study that revealed that the group formed an evolutionary lineage well differentiated from other rice mice related.

How to identify it

Small-to-medium-sized rodent, red brown fur, noticeably lengthy and sharp focique compared to other related species, and long tail. It differs from other species of its same group mainly by that longer focique, although field identification remains difficult without capture.

Signs and tracks

Footprint with 4 front fingers and 5 rear fingers, 1.5-2 cm rear, similar to that of other similar-size sotobosque rodents.

Habitat and range

Tropical wet rainforest, with dense subsoil, from low lands to middle mountain ranges. Distributed from southern Mexico to northern South America.

Diet

Omnivorous, it feeds on seeds, fruits and insects from the subsoil.

Behaviour

Solitary, of nighttime activity, it travels mainly on the soil of the underground.

Conservation

Its populations are considered stable in most of its area of distribution.

Threats

Deforestation and fragmentation of the rainforest by agricultural and livestock expansion in some areas of its area.

Other accounts in Cricetidae

See all species accounts for rodents · Full species index

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