Shortridge's Pygmy Rock Mouse

discussion

Discussion: Reviewed by Skinner and Smithers (1990) and de Graaff (1997 ll). Roberts (1951) treated shortridgei as a subspecies of P. bruchus, and Meester et al. (1986) listed it as a subspecies of P. collinus. However, Thomas’ species description correctly expressed the distinctness of the animal; also see Schlitter (in Meester et al., 1986) and Skinner and Smithers (1990). The larger size of P. shortridgei, darker fur with a less silky texture, and lack of postaxillary teats clearly separate it from P. collinus, a judgement based upon AMNH and FMNH specimens, which also inform our estimate of its geographic range. Crawford-Cabral (1998) recorded P. shortridgei only from the vicinity of Ruacana Falls, S Angola near the Namibia border, and speculated that the specimen (AMNH 81915) from farther north at Coporolo represented P. collinus. External and cranial morphology of the Coporolo specimen falls within the range of variation in P. shortridgei (as identified by Hill and Carter, 1941: 104), not P. collinus. The two species overlap in distribution in SW Angola and N Namibia but have not been collected at the same place.

Order Rodentia - Family Nesomyidae

distribution

Distribution: W and S Angola and N Namibia (S to Erongo Mtns and Okahandja region); limits unknown.

Order Rodentia - Family Nesomyidae

materials_examined

Type Locality: Extreme S Angola, Ruacana Falls, 3350 ft (1021 m).

Order Rodentia - Family Nesomyidae

discussion

COMMENTS: Roberts (1951) treated shortridgei as a subspecies of P. bruchus, and Meester et al. (1986) listed it as a subspecies of P. collinus. However, Thomas correctly expressed the distinctness of the animal by describing it as a species, which was also Schlitter's evaluation (in Meester et al., 1986), and that of Skinner and Smithers (1990). The larger size of shortridgei, darker fur with a less silky texture, and lack of postaxillary teats clearly separate it from P. collinus, a judgement based upon specimens in the American Museum of Natural History and the Field Museum of Natural History. Our estimate of its geographic range, which overlaps that of P. collinus, is also derived from those series.

Order Rodentia - Family Muridae