492.

Namaqua Rock Rat

Micaelamys namaquensis

French: Rat namaquois / German: Namaqua-Buschlandratte / Spanish: Rata de roca de Namaqua

Other common names: Namaqua Aethomys, Namaqua Micaelamys, Namagqua Rock Mouse

Taxonomy. Gerbillus namaquensis A. Smith, 1834,

“Little Namaqualand,” Cape Province, South Africa. Restricted by G. C. Shortridge in 1942 to “Witwater,” Kamies-berg Region, Cape Province, South Africa.

Genus Micaelamys was previously included in Aethomys, but chromosomal, morphological, and molecular data support its recognition as a distinct genus. Monotypic.

Distribution. Widespread in S Africa, including W Angola, Namibia, Botswana, extreme S Zambia, Zimbabwe, C Mozambique, S Malawi, Swaziland, Lesotho, and South Africa.

Descriptive notes. Head-body 80-147 mm,tail 107-197 mm, ear 11-24 mm, hindfoot 16-32 mm; weight 33-89 g. The Namaqua Rock Rat’s fur is yellowish brown to reddish brown grizzled with black above, and white to pale gray or pale yellowish orange below. Tail is very long (c.140% of head—body length), brownish black above and below, coarsely scaled and sparsely haired. Female has 1+2 = 3 pairs of nipples. Karyotype 2n = 24.

Habitat. Rocky outcrops in savanna and semiarid areas.

Food and Feeding. Diet is mostly composed of grass and foliage, also seeds and insects. Cecum of the Namaqua Rock Rat is large, as is the case with other grass specialists.

Breeding. Reproduction is seasonal and confined to wet season, with births toward end of wet season orearly dry season. Young are born altricial and nipple-cling for about two or three weeks. Gestation period exceeds 22 days.Litter size 1-7.

Activity patterns. Namaqua Rock Rats are nocturnal, terrestrial and partly arboreal.

Movements, Home range and Social organization. Namaqua Rock Rats nest singly, in pairs, or in small groups. Mean home range is 3100 m®. In the Namib Desert, home ranges of males did not overlap those of other males, and female home ranges likewise did not overlap; those of males and females, however, didoverlap. In captivity, intrasexual aggression was observed.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as Aethomys namaquensis).

Bibliography. Baker et al. (1988), Choate (1972), Chimimba et al. (1999), Ducroz et al. (2001), Happold (2013a), Lecompte et al. (2008), Linzey & Kesner (1997a, 1997b), Monadjem et al. (2015), Musser & Carleton (2005), Muteka et al. (2006a), Russo (2003), Shortridge (1942), Visser & Robinson (1986), Withers (1979).