Otolithes de poissons pliocènes du sud-est de la France

• Main Authors: Nolf, D., Cappetta, H.
• Format: Article in Journal/Newspaper
• Language: French
• Published: 1988
• Subjects: Biostratigraphy; Fish; New taxa; Otoliths; Pliocene; Sedimentary rocks; Tertiary; Osteichthyes; France; Planktonic foraminifera
• Online Access: https://www.vliz.be/imisdocs/publications/276554.pdf

Otoliths collected from nine localities in the Lower and Middle Pliocene blue marls of southern France revealed the presence of 118 teleost taxa, including 80 named species. Three new species are introduced: Pseudophichthys escaravatierensis , "genus Bythitinorum" vonhachti and Cepola neogenica . The associations studied belong to five different biozones of planktonic foraminifera in the Lower and Middle Pliocene. The relationships of these Pliocene teleost faunas to the Tortonian and Recent Mediterranean faunas are analysed. Because major problems exist in matching otolith-based species with those erected for osteological material from Messinian localities, our comparisons are based exclusively on data obtained from the otoliths. Fifty of our 80 identified species appear only in the Pliocene. This indicates that at the beginning of the Piocene, the Mediterranean realm was subject to extensive faunal replacement. All the studied associations indicate higher temperatures than those of the present day Mediterranean. In the studied area, the associations from the basal Pliocene ( Spaeroidinellopsis Acme-zone) at Saint-Martin-du-Var clearly indicate a bathyal environment, corresponding to depths of 300-500 m or even more. Ascending the stratigraphic column, the successive associations in the Pliocene rias of Southeastern France indicate decreasing depths, corresponding to the progressive filling of these basins. In the studied area, data on the teleosts of the terminal Pliocene are lacking, but faunas of this age are known from Southern Italy. They show that the Paleomediterranean fauna, which was substantially modified at the beginning of the Pliocene, appears near the end of this period as a warm water fauna, trapped in a basin where deterioration of climatic conditions led progressively to extinction. The Recent bathyal fauna of the Mediterranean appears extremely impoverished, but the littoral fauna conserves certain aspects of warmer waters, as is apparent in the prolific evolution of gobiids, labrids and blenniids.