19.

Southern African Spiny Mouse

Acomys spinosissimus

French: Acomys de Peters / German: Zwergstachelmaus / Spanish: Raton espinoso de Africa meridional

Other common names: Least Spiny Mouse, Southern Spiny Mouse

Taxonomy. Acomys spinosissimus Peters, 1852,

Buio and Tete, Mozambique.

Acomys spinosissimus was recognized by various authors as valid in early classifications, but confusion arose when it was synonymized with A. cahirinus, A. subspinosus, and A. selous: by J. R. Ellerman and colleagues in 1953. Some debate about distribution of A. spinosissimus also occurred until the last revision in 1986. Genetic and molecular analyses of A. spinosissimus also pointed to its validity, morphological limits, and distinction from A. selousi and A. subspinosus . The last molecular and morphometric analyses of the A. spinosissimus species complex showed that it has three different clades and specimens from Mozambique and Malawi belong to A. spinosissimus sensustricto, in contrast to Tanzanian specimens attributed to A. muzer and A. ngurui and Zambezian specimens to A. selousi . Chromosomal complement of A. spinosissimus is not known because all previously attributed karyotypes to it were either A. ngurui or A. selousi . Monotypic.

Distribution. From S DR Congo, NE Zambia, and N Malawi S to Zimbabwe and Mozambique, N of the Limpopo River; S limits uncertain.

Descriptive notes. Head-body 79-97 mm, tail 67-90 mm, ear 12-15 mm, hindfoot 12-19 mm; weight 20-31 g. The Southern African Spiny Mouse is small, with abundant spiny hairs covering entire back and rump. Dorsum is gray to light brown, flanks are pale, and belly is pure white. Tail is 80-90% of head-body length. Two pairs of mammae are visible. It has a peculiar dental pattern, the prelobe of M,is characterized by two very elongated anterior cusps well fused to the two posterior ones, the latter being well fused.

Habitat. Mopane ( Colophospermum mopane, Fabaceae) woodlands. The Southern African Spiny Mouse is associated with rocks and boulders.

Food and Feeding. Diet mainly contains insects and seeds. Beetles, ants, larvae, cockroaches, and other arthropods are eaten in Malawi. Diets in Mozambique changed from 60% insects in the wet season to 75% in the dry season.

Breeding. Reproduction is seasonal in Malawi, with most pregnancies and births occurring during the wet season. Litters have 2-5 young (average 3-2), and a female can produce nine young in three litters during five months. Young are precocial and weaned at c.26 days of age.

Activity patterns. Southern African Spiny Mice are nocturnal; they hide during the day in crevices among rocks and to endure droughts.

Movements, Home range and Social organization. Southern African Spiny Mice are not aggressive when trapped in pairs or in captivity, suggesting they are social.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Southern African Spiny Mice are abundant and represent 24-46% of rodent population captured in Malawi and Mozambique.

Bibliography. Allen (1939), Baréme et al. (2001), Denys et al. (1999), Dieterlen (2013f), Dippenaar & Rautenbach (1986), Ellerman et al. (1953), Gliwicz (1987), Hanney (1965), Happold & Happold (1991), Verheyen et al. (2011).