124.

Afghan Vole

Microtus afghanus

French: Campagnol dAfghanistan / German: Afghanistan-Wihimaus / Spanish: Topillo de Afganistan

Taxonomy. Microtus (Phaiomys) afghanus Thomas, 1912, Golran, Herat, Afghanistan.

Microtus afghanus 1s in subgenus Blan-Jfordimys. Morphologically and genetically, it is sister species to M. bucharensis. Three subspecies recognized.

Subspecies and Distribution.

M.a.afghanusThomas,1912—STurkmenistan,NEIran,andAfghanistan.

M.a.balchanensisHeptner&Shukurov, 1950—WTurkmenistan(GreatBalkhanMts).

M. a. dangarinensis Golenishchev & Sablina, 1991 — SW Tajikistan (Khatlon Region).

Descriptive notes. Head-body 65-125 mm, tail 12-38 mm, ear 7-14 mm, hindfoot 9-26 mm; weight 16-61 g. Female Afghan Voles are larger than males. Fur color of head and upperparts varies from pale yellowish to pale gray, underparts are whitish, and tail is uniformly light throughout or indistinctly bicolored and ¢.33% of headbody length. Sole of foot has six plantar pads. Auditory bullae are large and inflated. M? has three inner and three outer salient angles. M| has three alternating triangles; anterior triangles T4 and T5 are confluent but isolated from anterior cup. Bacula are 3-3—4-1 mm long, with narrow bases (widths of 1-1-1-4 mm), and long median (0-9-1-4 mm) and lateral (0-7-1-2 mm) processes. Chromosomal complement has 2n = 58 and FN = 60.

Habitat. Deserts, piedmont semi-deserts, savannas, and mountain steppe at elevations of 200-3700 m. The Afghan Vole prefers habitats with loess substrate and dense grass and forb vegetation.

Food and Feeding. The Afghan Vole feeds mainly on green parts of plants and flowers but also roots and seeds. About 100 species of plants are eaten, but main foraging plants are Carex physodes, C. pachystylis (both Cyperaceae), and Poa bulbosa ( Poaceae). Diets change seasonally. In February—April, main component is green parts of sedges, grasses, and annual forbs. In May-June, Afghan Voles feed mainly on unripe seeds of grasses and forbs. In July—January, diet contains almost exclusively roots of sedges and bulbs of P. bulbosa, but in extremely wet and warm winters that stimulate vegetative growth, green plant parts are eaten. Roots of sedges and bulbs are stored in special chambers in burrows; caches are 0.8-1.4 kg/burrow.

Breeding. Breeding of wild Afghan Voles was recorded in September—May. Intensity peaks in March-April, and there are no litters born in June-August. Litters have 1-13 young (averages 3-6-6). Females can produce up to 2-4 litters/year. Gestation lasts 21-22 days.

Activity patterns. Afghan Voles are mainly diurnal. In summer, there are two peaks of activity: 06:00-09:00 h and 15:00-19:00 h. In winter, activity peaks at midday.

Movements, Home range and Social organization. Afghan Voles live in large colonies (family groups) occupying a single complex burrow. Burrows cover surface areas of 5-45 m? and each burrow has one nest chamber (8-14 cm in diameter) at depths of 50-120 cm (usually 80-90 cm) and several storage chambers. There are 2—4 oblique and 1-3 vertical tunnels leading from the nest to the ground’s surface; oblique tunnels abundantly branch near surface. Total lengths of tunnels are 30-50 m (up to 70 m); mean number of entrancesis 18, but there can be up to 100. Contacts among individuals are accompanied by acoustic communication expressed in quiet or sharp squeals. Afghan Voles do not emit alarm calls on their own but escape to burrows at alarm calls of the co-occurring Great Gerbils ( Rhombomys opimus).

Status and Conservation. Classified as Least Concern on The IUCN Red List (as Blan-Sfordimys afghanus).

Bibliography. Bannikova et al. (2009), Davydov (1988), Golenishchev & Sablina (1991), Gromov & Erbajeva (1995), Hassinger (1973), Marinina (2005c¢), Niethammer (1970), Siahsarvie et al. (2005).