577.

African Wading Rat

Colomys goslingi

French: Rat de Gosling / German: Afrikanische Waldbachmaus / Spanish: Raton vadeador de Africa

Other common names: African Water Rat, Velvet Mouse, Velvet Wading Rat

Taxonomy. Colomys goslingi Thomas & Wroughton, 1907, “Gambi, Welle River]. [= Uele River],” DR Congo .

Because of convergent similarities between C. goslingi and Nilopegamys plumbeus, they were previously confused as the same species, but several diagnostic characters distinguish them. Five previously described subspecies are probably not valid. Monotypic.

Distribution. Disjunct range from Cameroon E to S South Sudan and W Kenya and S throughout NE & S DR Congo to NE Angola and NW Zambia, with an isolated record from Liberia.

Descriptive notes. Head-body 120-132 mm, tail 155-180 mm, ear 18-20 mm, hindfoot 32-38 mm; weight 45-64 g. Dorsal fur of the African Wading Rat is buffy brown, dense, and velvety, making it buoyant and waterproof. Ventral fur, sides of

body, arms, and legs are pure white. Muzzle is thickened, with dense vibrissae to probe for aquatic invertebrates in shallow streams. Brain size is enlarged compared with similarsized rodents. Ears are small and darkly colored, with small auricular white spots. Tail is very long (c.130% of head-body length), darker above than below, and scaly. Hindlimbs are long (30-37% of head-body length), with partly webbed toes. Forefeet and hindfeet are white, with four long digits on forefeet (first digit is rudimentary but with small claw) and five long digits on hindfeet.

Habitat. Streams in tropical rainforest at 400-3200 m (less common below 800 m).

Food and Feeding. The African Wading Rat mostly eats aquatic invertebrates, butit also preys on tadpoles, small fish, and terrestrial invertebrates.

Breeding. In DR Congo, pregnant African Wading Rats and youngwere recorded in September-March. Mean number of embryos per female was 2 (range 1-3). Both sexes become sexually active at weights of ¢.50 g.

Activity patterns. The African Wading Ratis nocturnal and semi-aquatic.

Movements, Home range and Social organization. African Wading Rats live singly or in pairs. Linear home ranges ofan individual or pair are 100-300 m of stream.

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

Bibliography. Dieterlen (1983), Dieterlen & Statzner (1981), Happold (2013a), Kerbis Peterhans & Patterson (1995), Kingdon (1974), Monadjem et al. (2015), Stephan & Dieterlen (1982).