First tetrapod footprints from the Permian of Sardinia

CITTON, PAOLO; CARATELLI MARTINA; MARCO ROMANO; MAGANUCO, SIMONE; RONCHI, AUSONIO; EVA SACCHI; NICOSIA, UMBERTO

Catania

Congreso; 89° Congresso della Società Geologica Italiana. 'Geosciences for the environment, natural hazards and 'cultural heritage'.; 2018

Società Geologica Italiana

The Torre del Porticciolo palaeontological locality (Alghero, N-W Sardinia, Italy) returned the skeletal remains of the first Permian basal synapsid from Italy, Alierasaurus ronchii (Romano & Nicosia, 2014, 2015; Romano et al., 2017), the largest late early Permian to early middle Permian non-therapsid synapsid known to date. Recently, other skeletal remains preliminarily attributed to a carnivorous non-therapsid synapsid were described from a second site, approximately from the same stratigraphic level within the Cala del Vino Fm.(Romano et al., 2018) and tetrapod tracks were found at a third site. This last finding represents the first ichnological record from the Permian of Sardinia. The general morphology of manus and pes tracks, the relative proportions and the position of digit I, enabled referring the new material to as Merifontichnus, anichnotaxon established from the uppermost portion (La Lieude Fm.) of Permian succession of the Lodève Basin (south France). Footprint dimensions, ranging between 4 cm and 10 cm in length, indicate two trackmakers of different body size, respectively of about 50 and about 100 cm in total length. The Cala del Vino Fm. turns out to be one of the few examples in the Permian of Europe of combined ichno- and body-fossil record. The two source of data, once integrated, provide different representations of the faunal composition, enhancingthe understanding of the faunal diversity of this area of Pangea during the latest early Permian to early middle Permian time interval. While the skeletal remains indicated medium-to large carnivorous basal synapsids and giant herbivorous caseid (i.e. Alierasaurus ronchii), the recently discovered ichnosite adds as further constituent of the terrestrial palaeofauna also a small animal represented by Merifontichnus trackmakers. The occurrence of this ichnotaxon from Italy allowed to confirm the early middle Permian age of the Cala del Vino Fm. The new material is the first reliable occurrence of Merifontichnus from Italy. Moreover, it represents to date an anticipation of the occurrence if compared to the alleged age of the La Lieude Fm., where Merifontichnus was established