La Polledrara di Cecanibbio: one of the richest Elephas (Palaeoloxodon) antiquus sites of the late Middle Pleistocene in Italy

La Polledrara di Cecanibbio site, together with the Castel di Guido site, is one of the richest deposits with Elephas (Palaeoloxodon) antiquus of the Italian late Middle Pleistocene (= Early Aurelian Land Mammal Age). The deposit, located NW of Rome at an elevation of about 83 m asl was discovered in 1984. About 750 m2 of a paleosurface belonging to an ancient stream bed were uncovered, with a high concentration of large mammal bone remains associated with lithic and bone industry. The site is included in the terminal series of the pyroclastic deposits of the ´Sabatino´ volcanic complex, up to now correlated with the Aurelia Formation and correlated with OIS 9. Recent stratigraphical research seems to indicate an erosive contact between the layers including La Polledrara di Cecanibbio site and the deposits of the Aurelia Formation. Therefore, La Polledrara might be older and can be correlated with a terminal phase of OIS 10. Among the most common species (Bos primigenius, Elephas antiquus, Cervus elaphus, Equus caballus, Canis aff. Canis lupus, Stephanorhinus sp.) Elephas bones are the most interesting, especially for the presence of two well preserved skulls. They offer a broader knowledge on the morphology of the Italian specimens of Elephas antiquus, up to now often studied on incomplete or deformed skulls. All skeletal elements are represented: numerous tusks, mandibles, isolated molar teeth and postcranial bones (some of them in anatomical connection), belonging at least to twenty-five individuals. The studies, presently in progress, may contribute to the knowledge of the morphological and biometrical variability of the Elephas antiquus populations of the late Middle Pleistocene and test the variability of some characters considered useful for gender determination.