594.

Smoky Forest Mouse

Chilomys fumeus

French: Chilomys sombre / German: Graue Kolumbien-Waldmaus / Spanish: Raton de bosque ahumado

Other common names: Smoky Chilomys

Taxonomy. Chilomys fumeus Osgood, 1912, “Paramo de Tama, head of Tachira River, Santander [= Norte de Santander], Colombia. Alt. 6,000-7,000 ft. [= 1829-2134 m].” This species is monotypic.

Distribution. Andes of N Colombia and W Venezuela.

Descriptive notes. Head-body 88-99 mm, tail 120-130 mm, ear 14-18 mm, hindfoot 22-25 mm; weight 15-22 g. The Smoky Forest Mouse is a small akodontlike sigmodontine, with dense, soft, and somewhat woolly fur. Back is entirely dark gray, and venteris slightly paler. Small whitish spot occurs on throat. Rostrum is slender, and eyes are minute; mystacial vibrissae are thick and pale and backwardly surpass pinnae. Ears are small, rounded, dark, and mostly hidden by fur. Pes is narrow, with welldeveloped claws. Tail is thick and long (c.133% of head-body length), unicolored, darker, and almost naked. The Smoky Forest Mouse and the Colombian Forest Mouse (C. instans) are very similar in general appearance and size. Minorcranial, postcranial, and dental differences distinguish them.

Habitat. Montane wet forest and montane rainforest, rarely extending into second growth, at elevations of 1830-2700 m. The Smoky Forest Mouse was captured in cloud forests of Venezuela at bases of rotting moss-covered trees, under moss-covered logs and fallen limbs, under lichen and moss-covered tree roots, and in openings and dense tangles of vines and bamboo in moist fern, moss, and lichen-laden cloud forest.

Food and Feeding. The Smoky Forest Mouse eats plant material, insects, and worms.

Breeding. A female Smoky Forest Mouse with well-developed teats and likely lactating was captured in July during the local wet season.

Activity patterns. The Smoky Forest Mouse is apparently nocturnal. It is terrestrial.

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The [UCN Red List. The Smoky Forest Mouse 1s considered rare; e.g. only two specimens were captured during c.20 days of trapping effort.

Bibliography. Linares (1998), Musser & Carleton (2005), Osgood (1912), Pacheco (2003, 2015a).