737.

Bunch Grass Leaf-eared Mouse

Phyllotis osilae

French: Phyllotis d/Asillo / German: Blschelgras-Blattohrmaus / Spanish: Raton orejudo de tusoc

Other common names: Bunchgrass Pericote

Taxonomy. Phyllotis osilae |. A. Allen, 1901, “Osila” [= Asillo, Puno,] Peru (alt. about 12,000 feet [= 3658 m]).”

Phyllotis phaeus 1s treated as subspecies of P. osilae by several authors, which needs additional research to verify. Monotypic.

Distribution. Andes of S Peru and W & C Bolivia.

Descriptive notes. Head—body 119-6 mm, tail 123-4 mm, ear 25 mm, hindfoot 26-2 mm; weight 57 g (means). Dorsum of the Bunch Grass Leaf-eared Mouse is buffy or ocherous to dark brown, more or less mixed with blackish. Cheeks and sides are pale buffy orange. Chest typically has median longitudinal streak, patch, or mid-ventral line. Ventral pelage is rarely sharply defined, usually dark gray with plumbeous basal parts. Inner and outer sides of ears are thinly haired and have dark brown edging. Tail is 80-130% of head-body length, bicolored, or with terminal one-half to two-thirds or more uniformly brown, with short hairs and weakly developed terminal pencil. Chromosomal complement is 2n = 70, FN = 68 in individuals from Puno, Peru.

Habitat. Bunch grass habitats on the Altiplano, notably in thick stands of Stipa ichu ( Poaceae), at elevations of 2700-4300 m.

Food and Feeding. The Bunch Grass Leaf-eared Mouse eats plant parts, some seeds, mycorrhizal spores, and arthropods.

Breeding. No information.

Activity patterns. The Bunch Grass Leaf-eared Mouse is strictly crepuscular.

Movements, Home range and Social organization. In Peru, density of the Bunch Grass [eaf-eared Mouse was 1:5 ind/ha.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Bunch Grass Leaf-eared Mouse has a wide distribution and presumably large overall population. Because it was separated form the Tucuman Leaf-eared Mouse (PF tucumanus) and the Walnut Leaf-eared Mouse ( P. nogalaris), an update of its conservation status is needed.

Bibliography. Dorst (1971, 1972a), Hershkovitz (1962), Jayat, Ortiz et al. (2016), Musser & Carleton (2005), Pearson (1958), Pearson & Ralph (1978), Pizzimenti & de Salle (1980), Redford & Eisenberg (1992), Steppan (1998), Steppan & Ramirez (2015), Steppan et al. (2007), Vargas et al. (2008).