637.

Soft-furred Oldfield Mouse

Thomasomys laniger

French: Thomasomys laineux / German: \Weichfell-Paramomaus / Spanish: Raton de erial de pelaje suave

Other common names: Butcher Oldfield Mouse, Soft-furred Thomasomys

Taxonomy. Oryzomys laniger Thomas, 1895, “from Bogota [Bogota],” Cundinamarca, Colombia.

This species is monotypic.

Distribution. C & E Andes ranges of Colombia.

Descriptive notes. Head-body 101-119 mm, tail 106-127 mm, ear 16-19 mm, hindfoot 24-26 mm; weight 25-36 g. The Soft-furred Oldfield Mouse is moderately small, with long, soft, and fluffy dorsal fur.

Dorsum is dull olivaceous gray, with hairs being slate-colored at base and olive at tips. Venter is similarly grayish but paler, with hair tips dull yellowish and counter-shaded relative to dorsal pelage. Mystacial vibrissae are very long, extending distinctly beyond posterior margin of pinnae when bent. Ears are relatively large and naked; post-auricular patches are conspicuous. Tail is similar to or longer than head-body length, slender,finely haired, unicolored, and occasionally with terminal white tip. Hindfootis relatively short, and metatarsals are dark brown. Chromosomal complement is 2n = 40 and FN = 40.

Habitat. Andean temperate forest and forest-paramo ecotone at elevations of 2600-3600 m.

Food and Feeding. The Soft-furred Oldfield Mouse eats fruit, seeds, and insects, with an increase of insects in wet season (June-August).

Breeding. Sexual maturity is reached at c.3-5 months old, and gestation is c.24 days.

Activity patterns. The Soft-furred Oldfield Mouse is terrestrial.

Movements, Home range and Social organization. Density generally increases in wet season; it was 8 ind/ha in Cerro Majuy, Cundinamarca.

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

Bibliography. Aguilera et al. (2000), Gémez-Laverde et al. (1997), Lopez-Arévalo et al. (1993), Pacheco (2003, 2015b), Pacheco, Ochoa & Gémez-Laverde (2008), Zuniga et al. (1988).