697.

Peruvian Vesper Mouse

Calomys sorella

French: Calomys du Pérou / German: Peru-Vespermaus / Spanish: Raton laucha de Peru

Other common names: Peruvian Laucha

Taxonomy. Eligmodontia sorella Thomas, 1900, “Eight miles south of Huamachuca, [La Libertad,] N.W. Peru. Altitude 3500 m.”

Species name changed as the original specific epithet sorella is the diminutive of the noun “soror” (sister) so it remains a noun and is invariable. Calomys sorella was included in synonymy several species, here treated as valid ( miurus, frida, etc.), that were elevated to specific status by H.

Zeballos and colleagues in 2014. Although additional work has demonstrate that some of their decisions were unwarranted, here they are preliminarily accepted. Monotypic.

Distribution. NW Peruvian Andes.

Descriptive notes. Head-body 70-89 mm, tail 43-67 mm, ear 16-19 mm, hindfoot 18-23 mm; weight 14-5-19 g. Dorsum of the Peruvian Vesper Mouse is dark sandy fawn and closely lined with black. Fur is long, smooth, very soft, fine, c.9 mm long on dorsum, 6-7 mm on venter, and profusely mixed with longer hairs ¢.16 mm. Fur is lighter on sides, with well-defined lateral line. Tips of longer dorsal hairs are shiny silvery. Venter is whitish, with hairsvisibly slaty gray basally and white terminally. Face is slightly grayer than dorsum; ears are of medium length, and their visible surfaces when folded are brownish fawn; and marked white patch occurs behind posterior bases. Upper surfaces of hands and feet are uniformly pure white. Tail is uniformly and tightly haired, brownish fawn above, darkening nearly to black at tips, and white below and on sides.

Habitat. Montane habitats including Polylepis (Rosaceae) woodland, shrubland, grassland, pasture and cropland at elevations above 2500 m.

Food and Feeding. No information.

Breeding. Pregnant and lactating Peruvian Vesper Mice with two and four embryos were reported in August and September.

Activity patterns. No information.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as C. sorellus, and including C. miurus and C. frida).

Bibliography. Almeida et al. (2007), Hershkovitz (1962), Olds (1988), Osgood (1914b), Pacheco et al. (2016a), Pearson & Patton (1976), Salazar-Bravo (2015c), SalazarBravo et al. (2013), Spotorno et al. (2001), Steppan (1993, 1995), Zeballos et al. (2014).