76.

Cape Gerbil

Gerbilliscus afer

French: Gerbille du Cap / German: Kap-Nacktsohlenrennmaus / Spanish: Gerbillo de El Cabo

Taxonomy. Tatera afra Gray, 1830,

near Cape Town, Cape of Good Hope, South Africa.

Species name changed, as the widely used afra is a feminine adjective and thus should be changed for gender agreement. Previously considered a member of genus Tatera, G. afer was further considered to belong to subgenus Gerbilliscus on basis of distinctive morphological characters. Genus Tatera was then reserved for the single 1. indica from Asia, and Gerbilliscus elevated to genus rank after morphological and molecular revisions. A taxonomic revision of the species was provided by J. A. J. Meester and colleagues in 1986, and some doubts about validity of the species were raised owing to close proximity to G. brantsii karyotype. Behavioural studies and hybridization tests by E. R. Dempster in 1996, however, showed its validity, and a molecular phylogeny by P. Colangelo and coworkers in 2007 showed that the two species belong to same clade but are distant relatives. Monotypic.

Distribution. SW South Africa.

Descriptive notes. Head-body 124-157 mm, tail 133-175 mm, ear 20-28 mm, hindfoot 28-44 mm; weight 78-113 g. Males are slightly larger than females. A mediumsized gerbil, the Cape Gerbil has red-orange dorsal pelage and white venter. Tail is rather long (c.110% of head-body length) and hairy, and does not terminate in a pencil. Tympanic bullae arelarge, but without extension in mastoid part of skull. Mammae formula is 2 + 2 = 8. Chromosomal complement has 2n = 44, FN = 66.

Habitat. The Cape Gerbil favors sandy soils and is common in some cultivated fields.

Food and Feeding. Like other gerbils, the Cape Gerbil is primarily herbivorous. Seeds, bulbs, and roots are preferred, but in some seasons some insects may be included in its diet.

Breeding. Reproduction is seasonal, from August to end of March, and ceases during cool wet season in winter. Gestation lasts about three weeks and litter size is 2-6 (average 4). Young are altricial, and are weaned at around 22-28 days.

Activity patterns. Cape Gerbils are nocturnal and terrestrial. In sands, they can build large burrows with many tunnels and openings, with a nestchamber in which shredded dry vegetation has been observed.

Movements, Home range and Social organization. There are no data on the social structure of Cape Gerbils, and adults are not aggressive in captivity. They communicate through audible calls, as well as ultrasonic ones.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as G. afra). No major threats are evident. The Cape Gerbil is considered a pestin some places.

Bibliography. Colangelo et al. (2007), Dempster (1996), Dempster & Perrin (1994), Dempster, Dempster & Perrin (1992), Happold (2013a), Meester et al. (1986), Qumsiyeh (1986).