87.

Pleasant Gerbil

Gerbillus amoenus

French: Gerbille charmante / German: Schonrennmaus / Spanish: Gerbillo cordial

Other common names: Charming Gerbil

Taxonomy. Dipodillus amoenus de Winton, 1902,

Giza province, Egypt.

Gerbillus amoenus was initially described in genus Dipodillus, but morphoanatomical and recent molecular studies have shown the latter not to be a valid genus. The species was synonymized either with G. dasyurus, G. campestris, or G. nanus, but D. M. Lay in 1983 elevated it to rank of separate species on basis ofits standard karyotype. This treatment was followed by G. G. Musser and M. D. Carleton in 2005 and D. C. D. Happold in 2013, but not by A. Monadjem and colleagues in 2015. S. Aulagnier and coworkers in 2009 determined that, in North Africa, G. amoenusreplaces G. nanus, which must be restricted to areas east ofthe Red Sea. Recent molecular studies of the G. nanus species complex and the Gerbillus genus by A. Ndiaye and colleagues corroborated that view. G. amoenusis considered a vicariant ofG. nanus, its sister taxon. Other poorly known species, such as G. grobbeni, G. vivax, and G. garamantus, may be synonyms of G. amoenus, but further studies are required. Monotypic.

Distribution. N Africa, from Mauritania E to Egypt.

Descriptive notes. Head—body 70-105 mm, tail 90-145 mm, ear 10-14 mm, hindfoot 19-27 mm; weight 11-36 g. The Pleasant Gerbil is a small gerbil with naked hindfeet. Short andsoft dorsal pelage is cinnamon to yellowish brown, and the venter is white. Tail is long (130% of head—body length), bicolored, and terminates in a brown pencil at tip. Some white spots may be seen on the cheeks, throat and chest, behind the ears, on the rump. Onthe skull, the tympanic bullae are inflated (30% oflength ofskull), and mandible has a high coronoid process and narrow ramus. Diploid numberis 2n = 52.

Habitat. Desert to semi-desert environments with hard soils, dense plant cover under trees (scrubs, bush, tamarisk and palm trees), and salt marshes, “wadis” (ephemeral riverbeds), oases, “dayas” (temporary ponds), and “sebkhas” (salt flats) with abundant bushes, and even cultivated fields.

Food and Feeding. Pleasant Gerbils are herbivorous, eating leaves, stems, and seeds. They maylive in the same places as the Fat Sand Rat ( Psammomys obesus) and feed on Euphorbiaceae and Amaranthaceae .

Breeding. No information.

Activity patterns. The Pleasant Gerbil is nocturnal and terrestrial. It digs simple burrows about 25 cm in depth under vegetation.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Pleasant Gerbil may be common but there is no recent data available.

Bibliography. Aulagnieret al. (2009), Happold (2013a), Kowalski & Rzebik-Kowalska (1991), Lay (1983), Monadjem et al. (2015), Musser & Carleton (2005), Ndiaye, Chevret et al. (2016), Ndiaye, Shanas et al. (2013), Ndiaye, Tatard et al. (2016), Osborn & Helmy (1980), Ranck (1968), Wassif (1956).