334.

Miahuatlan Cotton Rat

Sigmodon planifrons

French: Sigmodon de Miahuatlan / German: Miahuatlan-Baumwollratte / Spanish: Rata de algodén de Miahuatlén

Taxonomy. Sigmodon planifrons Nelson & Goldman, 1933, “Juquila, southwestern Oaxaca, Mexico (altitude 5000 feet [= 1524 m]).”

This species is monotypic.

Distribution. Limited to Pacific slope of Sierra de Miahuatlan, S Oaxaca, Mexico.

Descriptive notes. Head-body 119 mm,tail 88-111 mm, ear 14 mm, hindfoot 29 mm. No specific data available for body weight. The Miahuatlan Cotton Rat is notable forits small size; upperparts are ocherous buff and ocherous tawny, mixed with black; dark hair is most numerous on top of head, ears, and back, thinning along sides; rumpis suffused with light tawny; underparts are dark gray, overlaid with dull white; forefeet and hindfeet are buffy grayish above; and tail is bicolored, dark brown above and lighter brown below. Cranium is small, relatively flat in lateral view, and weakly ridged; auditory bullae are small; rostrum is slender; and upperincisorsare slightly recurved. Karyotype is unknown.

Habitat. Moist slopes covered with vines and shrubs in deciduous tropical forests at elevations of 1000-2300 m.

Food and Feeding. Diet is presumably herbivorous to omnivorous.

Breeding. No information.

Activity patterns. The Miahuatlan Cotton Rat is presumably diurnal and nocturnal.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Endangered on The IUCN Red List. The Miahuatlan Cotton Rat has a small distribution and presumably small overall population. It has likely experienced severe fragmentation and loss of habitat from transformation for tourism and agriculture.

Bibliography. Alvarez-Castafieda, Castro-Arellano, Lacher, Vazquez & Arroyo-Cabrales (2008), Carleton et al. (1999), Ceballos (2014a), Corley & Bradley (2014a), Goodwin (1955a, 1959b), Musser & Carleton (2005), Nelson & Goldman (1933).