S Carboni

NEW FOSSIL VERTEBRATE REMAINS FROM SAN GIOVANNI DI SINIS (LATE PLEISTOCENE, SARDINIA): THE LAST MAUREMYS (REPTILIA, TESTUDINES) IN THE CENTRAL MEDITERRANEAN

New fossil vertebrates from the most representative Upper Pleistocene section (Tyrrhenian, MIS 5e) of the outcrop of San Giovanni di Sinis (Oristano, Sardinia) are here reported and described. The fossils, although scarce and fragmentary, document the occurrence of a terrapin ( Mauremys sp.) and the endemic Sardinian deer ( Praemegaceros cazioti ). Significant is the occurrence of the terrapin because it is the youngest representative of the genus in the central Mediterranean area where it is extinct at present. The Late Pleistocene extinction of Mauremys in Italy follows the same pattern of other Mediterranean reptiles, in being in some cases delayed on the islands. A comparison of the modern range of Mauremys and that of the pond turtle, Emys , as well as of their past ranges as evidenced by the fossil record, might suggest that some sort of thermophily (at least during pre-hatching stages) characterized the former taxon and is responsible for its past and present distribution. SHORT NOTE

THE TYRRHENIAN SECTION OF SAN GIOVANNI DI SINIS (SARDINIA):STRATIGRAPHIC RECORD OF AN IRREGULAR SINGLE HIGH STAND

A new analysis of the most representative Upper Pleistocene (Tyrrhenian, MIS 5e) section of San Giovanni di Sinis (Oristano, Sardinia) has provided a more detailed genetic stratigraphy of a low wave energy beach and temperate lagoon up to emerged peri-lagoonal facies deposits. These peri-lagoonal facies contain remains of fossil vertebrates, which, though few and fragmentary, bear witness to an at least temporary freshwater palaeoenvironment and the presence of deers and terrapins. Besides, the stratigraphy of this outcrop shows shoreface-backshore sandstones overlaying an erosion surface cut on the vertebrate-bearing layers. Facies analysis and sequence stratigraphy of the succession have provided support to a new eustatic interpretation significance. In fact, there appears to be evidence of one irregular single eustatic highstand, rather than two eustatic peaks as previously believed. The facies evolution and the local stratigraphic disconformities are interpreted as being associated with a lateral shift of the depositional environment within the same system formed during the MIS 5e sea level variations. As sea water level continued to rise so an erosional unconformity, caused by wave ravinement, formed between the low wave energy beach-lagoon sequence and the successive wave dominated beach facies sequence. This interpretation is supported by comparison with other sections of the Tyrrhenian in western Sardinia. The maximum sea level attained during the Tyrrhenian stage is a clear indication of a warm-temperate climate which can be correlated to the well known orbital interglacial configuration when the eustatic signal of Greenlands ice sheet melting occurred. SHORT NOTES