Mus terricolor Blyth 1851

559.

Earth-colored Mouse

Mus terricolor

French: Souris terreuse / German: Erdfarbene Maus / Spanish: Raton terrizo

Other common names: Indian Pygmy Field Mouse

Taxonomy. Mus terricolor Blyth, 1851,

“S. India.”

Treated as “M. dunn?’ in subgenus Mus by J. T. Marshall in 1977. It was subsequently lumped into M. booduga, but morphomet- ric, chromosomal, and mtDNA studies summarized by G. G. Musser and M. D. Carleton in 2005 confirmed its validity as a separate species, pointing out that M. dun- mi was a junior synonym. Recentrobust phylogenies show thatit is a basal taxon of the “ M. booduga clade”, within the subgenus Mus. Monotypic.

Distribution. E Pakistan, India, Nepal, and Bangladesh. Introduced into NE Sumatra.

Descriptive notes. Head-body 53-70 mm, tail 51-70 mm, ear 9-11 mm, hindfoot 14-16 mm. No specific data are available for body weight. A small mouse with dorsal pelage variable from dark gray to brown, belly white to gray. Fur is short and soft, not spiny. Tail is unicolored and either equal to or slightly smaller (c.99%) than the headbody length. Chromosomal complement is 2n = 40.

Habitat. Probably found in a wide variety of habitats.

Food and Feeding. The Earth-colored Mouse probably eats seeds and green parts of plants.

Breeding. The Earth-colored Mouse is a seasonal breeder, with most of the reproduction corresponding to the periods of harvesting crops (rice, wheat); however, can breed throughout the year. Litter size variable, 2-19, with a mean of eight.

Activity patterns. Earth-colored Mice are terrestrial and nocturnal. They remain inside the burrow during the day.

Movements, Home range and Social organization. Burrows are situated at a depth of c.20 cm, and the nest is situated at the base of the burrows. Nest chambers measure 13— 14 cm in diameter and tunnels 2-5 cm wide. Small mounds of minute damp soil pellets can be found at the entrance. Larger mounds were seen at the entrance of breeding or family burrows with young; the young were found in globular nests padded with dried grass and straw. The Earth-colored Mouse uses irrigation mounds to dig its burrows more superficially than does the Little Indian Field Mouse (M. booduga). Beside family burrows with young, simple burrows were occupied by adult males.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Aplin, Brown et al. (2003), Arora et al. (2015), Corbet & Hill (1992), Marshall (1977a), Musser & Carleton (2005), Shimada etal. (2010), Singh et al. (2009), Suzuki & Aplin (2012).