Distribution patterns of European lacustrine gastropods: a result of environmental factors and deglaciation history

Contemporary climate and deglaciation history have received strong support as drivers of species richness and composition for several European taxa. We explored the influence of these factors on patterns of species richness and faunal composition of 244 freshwater gastropod species from 898 European lakes. We evaluated the influence of late Pleistocene deglaciation and seven physiographical and climatic factors on gastropod distributions using multiple linear regression models. We investigated species beta diversity patterns and the influence of species dispersal abilities and/or environment on species composition between lake subsets with different deglaciation history. Contemporary factors and deglaciation history explain parts of variation in species richness across European lakes. Beta diversity analysis revealed moderate to high differences in species composition between the predefined groups. Patterns of species replacement and species loss indicate that lacustrine gastropod faunas of formerly glaciated areas are subsets of non-glaciated ones. Dispersal limitations and environmental gradients control patterns of beta diversity within different lake subsets. We find strong support that the distribution of European limnic gastropods, at least partially, carries the imprint of the last Ice Age. The differences in species richness and composition point towards a gradual, ongoing process of species recolonization after deglaciation.