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Black-eared Rice Rat

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

Description

It shares the genus recently established with other Mesoamerican rice mice, and its name refers to the notably dark ears that contrast with the rest of its fur, a feature that helps to distinguish it from very similar relatives within the same group. It lives in tropical wet rainforest and transition forest from western Mexico to Central America, where it forages mainly by the soil of the sotobosque between the leaf. Like the rest of species of its group, it was moved in 2024 from the genus Handleyomys to the new genus that groups seven rice mice from the so-called "alfaroi group", a recent taxonomic change based on detailed genetic and morphological analysis.

How to identify it

Small-medium-sized rodent, red brown fur, notably dark ears that contrast with the rest of the fur, and long tail. It differs from other related species of its same group mainly by that dark coloration of the ears, although safe identification in the field continues to require capture in most cases.

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 rainforest and transitional forest, with dense subsoil, from low lands to mid-mountain quarters.

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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