668.

Andean Mouse

Andinomys edax

French: Andinomys vorace / German: Eigentliche Andenmaus / Spanish: Raton de los Andes

Other common names: Andean Rat

Taxonomy. Andinomys edax Thomas, 1902, “El Cabrado, between Potosi and Sucre [Potosi], Bolivia. Altitude 3700 metres.”

Validity of the form A. edax lineicaudatus, from time to time ranked as a separate species, a subspecies, or just a junior synonym of edax edax, needs further taxonomic consideration. A recent published revision concludes that Andinomys consists of a single species, although it includes significant genetic divergences among clades. Monotypic.

Distribution. Andes and high Andean environments in S Peru, extreme N Chile, SW Bolivia, and NW Argentina .

Descriptive notes. Head-body 134-182 mm,tail 107-160 mm, ear 22-29 mm, hindfoot 28-35 mm; weight 66-80 g. The Andean Mouse is moderately large and heavybodied. Furis soft and lax, dorsum and sides are drab, and underparts are buffy white, with basally slate-colored hair. Tail is 60% to nearly 100% of head-body length; it is sharply bicolored, densely furred, but lacks a terminal pencil. Mystacial vibrissae are numerous but short. Forefeet and hindfeet are well-haired on their upper surfaces, covered with white hair above, and silvery-white ungual tufts extend well beyond claws. Fifth digit of hindfoot (not including claw) reaches at least to base (often to middle) of second phalanx of fourth digit; palmar pads enlarged but not fused. Ears are comparatively small and look rounded, with fine gray edging. Eight mammae are present.

Habitat. Variety of habitats from subtropical mountain forests to, more typically, semiarid Puna and pre-Puna at elevations of 650-4500 m (mostly above 3000 m). The Andean Mouse mainly lives in high-elevation grasslands and related ecotonal highland systems, but it has not been recorded in the most arid part of the Andean Altiplano.

Food and Feeding. Molarstructure (prismatic crowns and triangulate cusps) and stomach contents suggest an herbivorousdiet,likely of mostly green herbs.

Breeding. Two females caught in April had signs of reproductive activity (open vaginas). No reproductive activity was observed in individuals captured in June-August. A pregnant female with three large embryos (crown-rump length 34 mm) was reported in mid-December in southern Peru. In north-western Argentina, females with closed vaginas were recorded in February-March, one lactating female and another with three embryos in February, and females with open vaginas in March (one with two embryos). Young individuals were trapped in February,June, andJuly. These observations suggest that the Andean Mouse is reproductively active from early Decemberto June.

Activity patterns. The Andean Mouse is nocturnal. It is primarily terrestrial and sometimes scansorial. It lives in round holes, quite clean, and insides are carpeted with very fine dried grass.

Movements, Home range and Social organization. No information.

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

Bibliography. Anderson (1997), Diaz & Barquez (2007), Dunnum, Vargas, Bernal, Zeballos, Vivar, Patterson, Pardinas, D'Elia & Jayat (2016), Hershkovitz (1962), Jayat, D'Elia etal. (2017), Jayat, Pacheco & Ortiz (2009), Ortiz & Jayat (2007), Pearson (1951a), Salazar-Bravo & Jayat (2015), Salazar-Bravo et al. (2016), Thomas (1902e, 1926b), Yepes (1935b).