4.

Golden Spiny Mouse

Acomys russatus

French: Acomys doré / German: Goldstachelmaus / Spanish: Raton espinoso dorado

Taxonomy. Mus russatus Wagner, 1840,

Sinai, Egypt.

Acomys russatus has always been considered distinct based on its morphology and molecular analyses. It has a remarkable karyotype (2n = 66, FN = 66 or greater), which is similar to that of A. lewisi from Jordan (2n = 66, FN = 76); they were synonymized by M. B. Qumsiyeh andcolleagues in 1986. Two subspecies recognized.

Subspecies and Distribution.

A. r. russatus Wagner, 1840 — Sinai (Egypt), Israel, Palestine (West Bank), SW Syria, Jordan, and Arabian Peninsula.

A. r. aegyptiacus Bonhote, 1912 — Eastern Desert ofEgypt.

Descriptive notes. Head—body 100-120 mm, tail 68-78 mm, ear 19-22 mm, hindfoot 20-21 mm; weight 40-77 g. Dorsum of the Golden Spiny Mouseis reddish. Tail length is less than 85 mm, and soles, palms of feet, and hands are black. Tympanic bullae are more voluminous than in the Northeast African Spiny Mouse ( A. cahirinus) or the Arabian Spiny Mouse ( A. dimidiatus).

Habitat. Rocky areas (boulders) in deserts from below sea level (Dead Sea) to Mount Sinai (2285 m).

Food and Feeding. The Golden Spiny Mouse does not store food but can store fat in its body. Experiments showed that Golden Spiny Mice entered torpor after ad libitum food intake was reduced by ¢.30%. Daily torpor (up to 19 hours long) was accompanied by reductions of metabolic rate and body temperature; torpor ended when food was provided.

Breeding. In Egypt and Israel, reproduction does not occur in winter. Gestation is 40 days, and litters have 1-4 young.

Activity patterns. The Golden Spiny Mouse is diurnal. It can be seen among rocks in the afternoon, which has been shown to be a strategy to avoid competition with other species of Acomys . The Golden Spiny Mouse becomes diurnal and crepuscular when syntopic with the Arabian Spiny Mouse, whichis nocturnal. Nocturnal populations of Golden Spiny Mice exposed to urine and feces of Northeast African Spiny Mice immediately became active an average of 6-8 hours earlier, becoming diurnal.

This pattern is observed in places where both species are sympatric, and chemical clues probably have fundamental roles in temporal segregation. Changes in activity patterns of Golden Spiny Mice were accompanied by changes in oxygen consumption and body temperature.

Movements, Home range and Social organization. The Golden Spiny Mouse is welladapted to life in deserts and spends all ofits time in rocky areas, unlike the Arabian Spiny Mouse that spends only ¢.50% of its time in such habitat. Home ranges of male and female Golden Spiny Mice overlap and average 340-726 m?. Densities are 15-46 ind/ha.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Lee et al. (1998), Baréme et al. (2000), Denys et al. (1994), Ehrhardt et al. (2005), Haim & Borut (1975), Haim & Rozenfeld (1993), Janecek et al. (1991), Kronfeld-Schor et al. (2000), Petter (1954), Qumsiyeh et al. (1986), Searight (1987), Shargal et al. (2000), Shkolnik (1971), Wahrman & Zahavi (1953).