In the rivers of the western and central parts of the Roztocze Upland, SE Poland, 37 species of Mollusca were found: 23 Gastropoda and 14 Bivalvia In the upper course of the Wieprz River 34 species of Mollusca occurred. In the Tanew River and its tributaries 24 species were found. In all investigated rivers bivalves of the genus Pisidium and the snail Ancylus fluviatilis predominated.
The distribution of the Turridae in the Pliocene of Catalonia (NE Spain) is heterogeneous. It appears to be determined to a greater extent by the particular autoecological traits of each species than by more general environmental factors. The area formed by the Pla de Barcelona and the Baix Llobregat may be regarded as a bio-geographical unit due to turrid species, which do not occur in other basins. The turrid distribution in the Alt Empordà basin manifests a high degree of environmental diversity among the different outcrops of the area, thus confirming the earlier provided taphonomic and biogeographic data. Species of the Turridae from Poble de Siurana (Alt Empordà) are also present in different parts of the Pla de Barcelona and Baix Llobregat areas. This indicates the existence of similar ecological enclaves in both basins, within a quite different general context.