Can the environment induce intra-variety changes of Helix pomatia conchological features?

Inter- and intra-specific genetically and phenotypically determined variations in snail morphological features are well documented. The same may be true even within the same species variety. The snails (Helix pomatia var. Banatica) were collected from two distinct sites, placed 100 km one from another and characterized by different climatic conditions (rainfall level, altitude, annual average temperature, and subtype of temperate climate): Oravi a and Timi oara area. Using bi - and tridimensional data processing, statistical, and biochemical analyses we assessed the cumulated actions of environmental factors on intra - variety changes of shell morphological features in relation to origin area. Formula proposed for shell tri-dimensional processing (shell volume) provided a reliable and faster method to assess variations among shell height, width, and depth than the multiple analyses of each feature apart. Similarly, aperture bi-dimensional processing (aperture area) successfully replaced the separated statistical analyses of aperture height and depth. Most biometric features, excepting shell thickness, presented a linked and proportional pattern among themselves. In addition, the sense of these relationships (direct or converse proportional) for shell height, width, and depth seemed to vary depending on location. We demonstrated that shell volume and aperture area tend to be larger in areas with higher annual rainfall level, altitude, and mean average temperature. Oppositely, shell thickness displayed a conversed relationship,possibly related to higher calcium content registered for the same population. Overall, our findings suggest that within the samespecies variety gastropod shells follow a genetic pattern of growing that allow the preservation of their geometric shape irrespectiveof the environmental conditions.