Données récentes sur les téléostéens du miocène et du pliocène d'italie

Abstract

The discovery of new fossil fish deposits or of new specimens in already known deposits has enriched our knowledge of the neogenic ichthyofaunal associations in the Mediterranean Basin. The teleostean ichthyofaunal association is both complex and diversified from the biogeographical, paleoclimatic and paleoecological points of view. In the Messinian, marine ichthyofauna evidently are followed, in the evaporitic phase, by euryhaline associations of low taxonomic diversity, which in certain deposits are associated with marine stenohaline forms. During the evaporitic phase, ichthyofaunal associations from tropical brackish water environments spread northwards from the coasts of Africa and the Middle East. In the Lower and Middle Pliocene, the ichthyofauna prevalently shows Atlanto-mediterranean biogeographical affinities connected with the reopening of communications with the Atlantic Ocean. Furthermore, species with strictly Indo-Pacific affinities are already present in the Mediterranean Basin this supports the hypothesis concerning the probability of the continued existance of marine environments of normal salinity in the eastern sector of the Mediterranean during the evaporitic phase. In the Upper Pliocene the tropical component of the ichthyofauna disappears from the Adriatic Basin, while some elements persist at lower latitudes.