Otomys fortior Thomas 1906

Charada Vlei Rat

Otomys typus fortior: Thomas 1906:302 (type locality— Ethiopia, Kaffa, Charada Forest, 1829 m); Allen 1939:348 (listed as valid subspecies); Ellerman 1941:321 (listed as valid subspecies); Bohmann 1952:45 (taxonomic revision, retained as valid subspecies).

Otomys fortior Dollman 1915 —Kaffa, Ethiopia.

Otomys typus ( fortior) Misonne 1974, Yalden et al. 1976 and Musser and Carleton 1993—without indication of rank.

Holotype: BMNH 6.11.1.29.

Type locality: Ethiopia, Charada Forest, Kaffa, 1829 m a.s.l..

Taxonomic notes: Otomys fortior shares a common karyotype of 2n = 58, NFa = 58 with O. typus and O. helleri, as well as higher number of eight laminae in M3. This is the most distinct species in the TYPUS group, both genomically (Figs 3–6) and ecologically (the only species living in forest clearings at relatively low elevation in south-western Ethiopia; Fig. 2). Morphological analysis did not show any special ecological adaptations to different environments.

Distribution: The species lives in tropical forests in south-western Ethiopia, west of the Omo River, from where we provide numerous new data [compared to Taylor et al. (2011)]. The elevational range of genetically confirmed records is 1360–2600 m a.s.l.. The specimens from the Jimma area were assigned to O. fortior based on geographic and ecological data. However, based on cranial characteristics, they are related to O. cheesmani (Taylor et al. 2011), which might be just an artefact of morphological analysis.