Changes in the External Morphology of Shells of Freshwater Bivalves of the Superfamily Pisidioidea Depending on the Geographic Location of Their Habitats

摘要

The study of morphological characteristics of freshwater invertebrates in different areas of their ranges is one of the directions of investigation of biogeographic laws. This is especially relevant for poorly studied groups of organisms, for which morphological traits are important taxonomic diagnostic criteria. One of such groups is the freshwater bivalves of the superfamily Pisidioidea. Although ample data regarding the morphology of mollusks classified into this group has been accumulated, variability of shell sizes has been considered thus far solely in the ecological aspect, irrespective of the geographical factor [1, 2]. For this reason, the goal of this study was to reveal morphological differences in the mollusks depending on the geographic location of their habitats.