Colomys goslingi Thomas and Wroughton 1907

Colomys goslingi Thomas and Wroughton 1907, Ann. Mag. Nat. Hist., ser. 7, 19: 380.

Type Locality: Dem. Rep. Congo, Orientale, Uele River, Gambi.

Vernacular Names: African Wading Rat.

Synonyms: Colomys bicolor Thomas 1912; Colomys denti St. Leger 1930; Colomys eisentrauti Dieterlen 1983; Colomys ruandensis Dieterlen 1983 .

Distribution: Recorded from Liberia (Lofa), Cameroon, NE Angola, NW Zambia, Dem. Rep. Congo, Ruanda, Uganda, E Kenya, S Sudan, and W Ethiopia (range mostly abstracted from Dieterlen, 1983); limits unresolved.

Conservation: IUCN – Lower Risk (lc).

Discussion: Study of external, cranial, and dental variation in context of taxonomic revision provided by Dieterlen (1983). Recent research by Rainer Hutterer and his colleagues (R. Hutterer, in litt., 1999) is uncovering a much greater range in morphological variation within and among geographic samples of Colomys than has been documented, which indicates the current definition of C. goslingi to be a composite of several separate species.

Colomys goslingi is most commonly found along banks of small and shallow flowing streams and pools in tropical evergreen rainforests (Dieterlen, 1983; Hatt, 1940 a), but has also been taken along streams in grassland far from forest (Hayman, 1966). Hayman supposed Colomys to "be a relict forest form" and its survival in regions where forests have retreated or been cleared "may be due to its aquatic specialisation which enabled it to continue to exist wherever any permanent water with sufficient bordering vegetational cover may provide its basic requirements" (p. 36). The species is a carnivore preying on limnetic macroinvertebrates and small vertebrates, and possesses special morphological and neurological adaptations as well as behavioral repertoire that are correlated with extracting such a diet from streams and pools (Dieterlen and Statzner, 1981; Stephan and Dieterlen, 1982; Kerbis Peterhans and Patterson, 1995). Colomys wades through the stream, using its front feet to sift mud and debris and its vibrissae–which are spread out over the water surface–to detect prey (colo is Latin for separating or sifting so Colomys means sifting mouse). Colomys goslingi is a member of an African guild of waders that includes species of Malacomys and Deomys ferrugineus: "Without swimming and while perched on elongate hind feet, all three consume insects and other small animals in shallow forest streams and pools" (Kerbis Peterhans and Patterson, 1995:329). Comparisons with Neotropical ichthyomyines provided by Voss (1988) and Kerbis Peterhans and Patterson (1995). Crawford-Cabral (1998) reviewed and mapped the few Angolan records. Habitat and altitudinal distribution on Ugandan slopes of Mt Elgon reported by Clausnitzer and Kityo (2001).