644.

Ucucha Oldfield Mouse

Thomasomys ucucha

French: Thomasomys de Voss / German: Ucucha-Paramomaus / Spanish: Ratén de erial de Ucucha

Other common names: Ucucha Thomasomys

Taxonomy. Thomasomys ucucha Voss, 2003, “at an elevation of 11,100 ft (3384 m) in the valley of the Rio Papallacta (ca. 3-5 km by trail NNW Papallacta), Provincia Napo, Ecuador.” This species is monotypic.

Distribution. Known only from the crest of E Andes Range in NC Ecuador (Carchi, Pichincha, and Napo provinces).

Descriptive notes. Head-body 94-109 mm, tail 122-151 mm, hindfoot 26-30 mm, ear 17-20 mm; weight 24-46 g. Fur of the Ucucha Oldfield Mouse is dense, fine, and soft. Dorsum is near brownish olive along flanks, shading to dark grayish brown mid-dorsally. Venter is dark neutral gray basally, with superficial wash of light neutral gray or glaucous, not sharply contrasting with dorsum. Mystacial vibrissae are moderately long, extending just behind pinnae when laid back alongside head; first genal (cheek) vibrissae is absent. Ears are sparsely covered with short, blackish hair, not contrasting conspicuously with color of head. Tail is long (122-125% of head-body length). Hindfoot is of moderate size and neither very narrow nor conspicuously broad, without gap between thenar and hypothenar pads.

Habitat. Grassy paramo, shrubby paramo and forest ecotone, grassy glades surrounded by forest, and deep inside subalpine rainforest at elevations of 3380-3800 m.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Ucucha Oldfield Mouse is nocturnal and terrestrial. It has been recorded on the ground, along rabbit trails or runways through dense grass or low herbs, in runways through moss or damp litter, under mossy debris, at bases of mossy trees, and along wet margins of small streams.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Vulnerable on The IUCN Red List The Ucucha Oldfield Mouse is known from a few locations that are threatened by conversion of native habitat to agriculture.

Bibliography. Arcos et al. (2007), Pacheco (2003, 2015b), Pacheco, Tirira & Boada (2008c), Voss (2003).