Environmental Factors Affecting the Conchological Variability of the Common River Snail Viviparus viviparus (L., 1758) (Mollusca: Gastropoda) in the Novosibirsk Reservoir, Russia

The shell variability of the common river snail ( Viviparus viviparus (L., 1758)), a species alien to Western Siberia, was studied using the methods of discriminant and dispersion analysis for the population of the Novosibirsk Reservoir. In different parts of the reservoir, the subpopulations of common river snail are formed, which differ in the shell proportions. A statistically significant relationship between the spatial differentiation of the shell shape and the depth of habitat was found. Differences in temperature and food availability in the coastal and relatively deep-water areas of the reservoir may have a leading role in morphological differentiation. The morphological changes in the common river snail, which occurred in a short time after the appearance of this species in the Novosibirsk Reservoir, indicate their ability to adapt quickly and testify to a high invasive potential of the species.