Shell Banding Polymorphism inCepaea vindobonensisin Relation to Habitat in Southeastern Poland

Abstract

We studied the frequencies of shell-banding variants of Cepaea vindobonensis (Férussac) in open, semi-open and shaded habitats in two geographically separate but climatically similar areas in southeastern Poland. The faint-banded phenotype was more frequent in open and semi-open habitats than in shaded areas. Within the dark-banded phenotype, those with missing bands were associated with open and semi-open habitats, and those with fusion of bands with shaded habitats. The feature most strongly associated with habitat type was the width of bands relative to the ground area. It was significantly higher in shaded habitats than in semiopen areas, in which it was significantly higher than in open habitats. Our study thus indicated the effect of local microclimatic selection on the frequencies of various phenotypes, resulting in light shells being more common in open habitats and dark shells in shaded areas. This association of shell characteristics with habitat type was more pronounced in the area where Cepaea vindobonensis inhabited more natural habitats and showed higher polymorphism.