641. Forest Oldfield Mouse Thomasomys silvestris French: Thomasomys sylvestre / German: \Wald-Paramomaus / Spanish: Raton de erial de bosque Other common names: Forest Thomasomys, Sylvan Thomasomys Taxonomy. Thomasomys silvestris Anthony, 1924, “Las Maquinas [Las Maquinas], on Santo Domingo trail, west of Corazon, Western Andes [Pichincha], Ecuador; altitude 7000 feet [=°2134°m].” This species is monotypic. Distribution. W Andes slope of Ecuador; records from E slope in Morona Santiago need confirmation. Descriptive notes. Head-body 95-127 mm, tail 139-157 mm, ear 18 mm, hindfoot 28-30 mm. No specific data are available for body weight. Dorsum of the Forest Oldfield Mouse varies from brownish cast (hairs slate-colored basally and tipped with raw umber or mummy-brown) to much darker, more sooty tone; venter is uniformly gray plumbeous, washed with light brown, and not countershaded with dorsal pelage. Mystacial vibrissae are moderately long and extend slightly beyond posterior margin of pinnae when bent. Ears are moderately long and clove-brown. Tail is distinctly long (112-150% of head-body length), slender, almost naked, and almost uniformly clove-brown above and slightly lighter below, with terminal white tip. Hindfoot is moderately long, narrow, and clove-brown above, with distinct gap between thenar and hypothenar pads. Habitat. Montane forest, subtropical forest, temperate forest, and adjacent paramo at elevations of 1800-4500 m. Food and Feeding. No information. Breeding. No information. Activity patterns. No information. Movements, Home range and Social organization. No information. Status and Conservation. Classified as Least Concern on The IUCN Red Lust. Bibliography. Anthony (1924a), Brito & Ojala-Barbour (2016), Lee et al. (2011), Luna & Pacheco (2002), Musser & Carleton (2005), Pacheco (2003, 2015b, 2016h), Tirira (2007), Voss (2003).

Published as part of Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Cricetidae, pp. 204-535 in Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona :Lynx Edicions on page 496, DOI: 10.5281/zenodo.6707142