Otomys unisulcatus F. Cuvier, 1829 . In E. Geoffroy and F. Cuvier, Hist. Nat. Mammifères, pt. 3, 6(60):1 -2 "Otomys cafre".

TYPE LOCALITY: South Africa, Cape Province, SW Karroo, Matjiesfontein, SW of Laingsburg (as designated by Roberts, 1946:318) .

DISTRIBUTION: NW Cape Province, through the Great and Little Karroo, to E Cape Province, South Africa.

SYNONYMS: albaniensis, bergensis, broomi, grantii.

COMMENTS: A species having a relictual distribution and exhibiting many traits interpreted as plesiomorphic for the subfamily (e.g., Bohmann, 1952). Genetic distance data reported by Taylor et al. (1989) suggest the inclusion of unisulcatus with species of Parotomys, an intriguing possibility that deserves substantiation with a broader taxonomic sampling. Allozymic variation unappreciable over species range and questions validity of subspecific divisions (see Van Dyk et al., 1991).