PALEOCOMUNITÀ A MOLLUSCHI BENTONICI DEL PLIOCENE DI VOLPEDO (Alessandria)

Abstract

The present paper deals with Pliocene molluscan assemblages coming from a stratigraphic section, some 30 m thick, surveyed near Cascinetta di Volpedo in the Alessandria Province. Its aim is to reconstruct and illustrate the originai commu­nities, as documented in 5 bulk-samples (25 dm³) taken from silty-clays and sandy-silts.
Known and/or inferred informations on species autoecology as well as a statistica! treatment of data enabled us to point out that Corbula (Varicorbula) gibba (Olivi) is the dominant taxon in each community, always accompanied by species linked to sandy and muddy bottoms, being the respective frequencies of these two latter stocks of Molluscs dependent from the grain size as well as from the amount of organic matter.