Paleogene: i vertebrati marini

The Paleogene marine fossil record of Italy is richer than the non-marine one but not uniformly distributed. Fossils of Paleocene age consist of a few teeth of chondrichthyans collected in two localities of Veneto. On the contrary fossil fishes (both cartilaginous and bony) of all Eocene stages are collected in many sites (especially from north-eastern Italy). Among them Monte Bolca (Veneto), ascribed to late Early Eocene, delivered many thousands of excellently preserved specimens of fishes belonging to more than 250 species. The assemblage of Monte Bolca is dominated by bony fishes with primitive or specialised characters belonging to evolutionary lineages with recent members, whilst primitive extinct groups are rather few. The assemblage characterises the reef environment and testifies the presence of a modern-like reef fish community during the first part of the Eocene in the Tethyan sea. The number of fish-bearing Oligocene localities of Italy is smaller. Also for this period the fossiliferous sites are concentrated in north-eastern Italy. Very interesting localities of “middle” Oligocene age are Chiavon (Veneto), where a tropical lagoon fish fauna has been collected, and Priabona (Veneto), characterised by a frankly marine assemblage. Among marine mammals sirenians are present in some Eocene sites of Veneto (with well preserved specimens) and in a few Oligocene sites of Veneto and Liguria. Very few and fragmentary cetacean fossils have been collected in Emilia in sediments of Late Eocene age.