77.

Balkan Snow Vole

Dinaromys bogdanouvi

French: Campagnol de Martino / German: Bergmaus / Spanish: Topillo nival de los Balcanes

Other common names: Martino’s Snow Vole

Taxonomy. Microtus (Chionomys) bogdanovi V. Martino & E. Martino, 1922, “Cetinje, Montenegro. Alt. 680 m. ”

Closest relatives to D. bogdanovi are not known with certainty, but it has frequently been identified among fossil taxa. Before being allocated to Dinaromys, D. bogdanovi was classified as the sole living member of a Tertiary genus Dolomys. It is currently believed that Dinaromys is closely related to Pliomys, a fossil genus that emerged in lower Pliocene and vanished 29,000-30,000 years ago. Phylogenetic analysis of D. bogdanoviretrieved three lineages, and the main division, dated at about one million years ago, might be indicative of cryptic species diversity (bogdanoviand longipedes). Morphologically, these lineages are remarkably invariant, possibly due to strong pressures of stabilizing selection for the normative phenotype. Six subspecies were recognized in the past. Three subspecies recognized.

Subspecies and Distribution.

D.b.bogdanoviV.Martino&E.Martino,1922—DinaricMtsEoftheNeretvaRiver,inBosniaandHerzegovina,Croatia,Kosovo,Montenegro,andNAlbania.

D.b.grebenscikoviV.Martino,1935—WMacedoniaandEAlbania.

D. b. longipedes Djuli¢ & Vidini¢, 1967 — Dinaric Mts W of the Neretva River, in parts of Croatia and Bosnia and Herzegovina.

Descriptive notes. Head-body 131-152 mm, tail 83-107 mm; weight 54-99 g. The Balkan Snow Vole is large, with long-tail. It resembles the European Snow Vole ( Chionomys nivalis) in color and body proportions. Tail of Balkan Snow Vole is longer than 50% of head-body length, hindfoot is also long (23-9-26-3 mm), and ears overtop pelage. Eyes are moderately large, and vibrissae are up to 60 mm. Females have three pairs of nipples: one pectoral and two inguinal. Pelage is long and soft, gray on back with shade of light buff and clouded white on belly; hair bases are slaty. Tail is covered with stiff hairs, moderately penciled, bicolored, dark brown above, and whitish below. Feet are white. Juveniles are bluish gray. Skull is compact and moderately ridged. Ridges converge in orbital region but never merge to form sagittal crest. Molars are low-crowned and develop roots in adults; length of roots correlates with age. Enamel band is rather thick, but there is little cement in reentrant loops. M, has five closed and alternating triangles, and M® is simplified, with short posterior loop.

Habitat. Rocky habitats, nearly always calcareous bedrock, at elevations of 10-2200 m, most often above 1400 m. The Balkan Snow Vole is a habitat specialist and elevational generalist. Underground caverns seem to be an important component of the habitat. A particularly suitable habitat is found in “dolines,” conical depressions that are irregularly scattered in undulating karst landscapes.

Food and Feeding. The Balkan Snow Vole mainly feeds on green parts. In spring and summer, plants are transported underground. In central Bosnia, plants were collected at entrancesto shelters, including sheep fescue ( Festuca ovina) and crested wheatgrass ( Agropyron repens), both Poaceae; germander speedwell ( Veronica chamaedrys, Scrophulariaceae); thistle ( Cirsium, Asteraceae); scabiosa ( Scabiosa leucophylla) and teasel ( Cephalaria), both Caprifoliaceae; rockrose ( Helianthemum vulgare, Cistaceae), harvestlice ( Aremonia) and cinquefoil ( Potentilla), both Rosaceae; bedstraw ( Galium, Rubiaceae); meadow rue ( Thalictrum, Ranunculaceae); European wild ginger ( Asarum europaeum, Aristolochiaceae); alpine rockcress ( Arabis alpina, Brassicaceae); field bindweed ( Convolvulus arvensis, Convolvulaceae); common bugle ( Ajuga reptans, Lamiaceae); and fern moss ( Hylocomium proliferum, Hylocomiaceae).

Breeding. The Balkan Snow Vole reproduce throughout the year, peaking between March and late October. Females are sexually mature in their second year and deliver, at most, 2 litters/season. Gestation is reported to be ¢.30 days, and numbers of embryos are 1-4/litter (mean 2-3). Life expectancy is up to 36 months.

Activity patterns. The Balkan Snow Vole moves by walking, running, jumping, and climbing. It climbs rocks, even very steep ones, and has been observed in shrubs and trees. Activity is mainly nocturnal but sometimes crepuscular and diurnal. In central Bosnia, only 15% of captures were during the day and the remaining 85% were at night.

Movements, Home range and Social organization. The Balkan Snow Vole is sedentary. In a study conducted in a system of 14 dolines scattered across 5-7 ha in central Bosnia, individuals moved only between dolines. Longest recorded movement was 220 m.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. The Balkan Snow Vole occupies a small area that is fragmented and shrinking.

Bibliography. Krystufek & Buzan (2008), Krystufek, Buzan et al. (2007), KryStufek, Engelberger et al. (2010), Krystufek, Klenovsek et al. (2012), Krystufek, Kolari¢ & Paunovi¢ (2000), Petrov & Todorovic (1982).