Black-tailed Thallomys

discussion

Discussion: Thallomys nigricauda and T. paedulcus are now recognized as occurring in the Southern African Subregion by Skinner and Smithers (1990), who also summarized some of the chromosomal, morphological, and ecological distinctions between the two species. They also suggested that herero and leuconoe may represent samples of T. paedulcus, but we examined the holotypes and they are examples of T. nigricauda. Musser and Carleton (1993: 669) wrote that " Morphological and geographic definitions of T. nigricauda are unsatisfactory. Appreciable geographic variation in body size, length of molar row, pelage coloration, and tail pilosity exists among samples and its significance will have to be assessed by critical systematic revision. " Results of such a study are presented by Taylor et al. (1995), who employed multivariate analyses of southern African samples already identified by chromosomal traits as either T. nigricauda (2 n = 47 - 50) or T. paedulcus (2 n = 43 - 47) and documented morphometric traits distinguishing samples of the two species, provided clearer resolution of their geographic distributions, and demonstrated broad sympatry in ranges. Crawford-Cabral (1998) reviewed

Order Rodentia - Family Muridae

distribution

Distribution: W and S Angola, Namibia, N South Africa, Zimbabwe, N Botswana, and SE Zambia; northern and eastern limits unknown. The range described here is mapped by Taylor et al. (1995), who also identified a skull from Kenya as possibly an example of T. nigricauda.

Order Rodentia - Family Muridae

materials_examined

Type Locality: Namibia, Great Namaqualand, Hountop (= Hudup or Hutop) River, west of Gibeon (Meester et al., 1986).

Order Rodentia - Family Muridae

discussion

COMMENTS: T. nigricauda and T. paedulcus are now recognized as occurring in the Southern African Subregion by Skinner and Smithers (1990), who also summarized some of the chromosomal, morphological, and ecological distinctions between the two species. They also suggested that herero and leuconoe may represent samples of T. paedulcus, but the holotypes are examples of T. nigricauda. Morphological and geographic definitions of T. nigricauda are unsatisfactory. Appreciable geographic variation in body size, length of molar row, pelage coloration, and tail pilosity exists among samples and its significance will have to be assessed by critical systematic revision.

Order Rodentia - Family Muridae