The recent record of in the south of the Central Russian Upland (Belgorod Region, Russia) provides the opportunity to study the alien populations structure at the stage of colonization of a new territory. High intra-and interpopulation variability of the shell in different parts of the range is revealed. Based on the allozyme and PCR-ISSR analysis, it was established that native and adventitious populations of a had the same level of genetic variability. The potential number of multilocus genotypes calculated for the Belgorod population indicate a further complexity of their genetic structure. The result of the ISSR analysis showed significant genetic differentiation (FST=0.746; p=0.01) of two adventive populations from the Belgorod Region, which indicates their different origin from the natural area.