Patterns of behaviour as an evidence for the taxonomical status of Lasiopodomys (Stenocranius) gregalis (Pallas, 1779) (Rodentia: Arvicolinae)

Narrow-skulled vole was previously assigned as a species of the subgenus Stenocranius Katschenko, 1901 of the genus Microtus Schrank, 1798, i.e. as Microtus gregalis (Pallas, 1779). However, molecular genetic analysis showed the relationships of this species with the genus Lasiopodomys Lataste, 1887, thus its current taxonomic status is as Lasiopodomys (Stenocranius) gregalis. The purpose of the present article is to present results of ethological analysis of mating behaviour as an evidence for the placement of the narrow-skulled vole in the genus Lasiopodomys. A study of sexual behaviour parameters of the narrowskulled vole compared with the parameters of some other species of the genera Lasiopodomys, Microtus and Alexandromys was carried out. The results showed the multiple-thrust stereotype of copulation, which includes separate intromissions and a very first mount with intromission, which ending with ejaculation. The number of ejaculations was small, from 3 to 5, and the genital stimulation rate averaged 100-106 thrusts. During the courtship, the singing and waltzing were moderately pronounced. Marking of the territory was realised by the application of the secretion of a specific flank skin glands. The dendrogram of similarity of sexual behaviour demonstrates that L. gregalis is close to the species of the genus Lasiopodomys. Clear difference between sexual behaviour of the studied vole in comparison with the species of the genus Microtus (Microtus s. str. and Sumeriomys) was noted. The level of inter-population differences in narrow-skulled vole was higher and exceeded these of many other species.