RASATOMARIA GENTILII GEN. N. N. SP - A NEW MIDDLE TRIASSIC PLEUROTOMARIOID GASTROPOD GENUS AND SPECIES FROM RASA DI VARESE (SAN SALVATORE FORMATION, SOUTHERN ALPS)

摘要

A new Middle Triassic (Uppermost Anisian, Illyrian) gastropod genus and species, Rasatornaria gentilii gen. n. n. sp., is described from the San Salvatore Formation from Rasa, an outer district of the town Varese (Lombardy, Italy). The studied specimens come from a diverse benthic marine assemblage, which is dominated by gastropods and bivalves. Based on ammonoids, this assemblage belongs to the Nevadites secedensis Zone. The new gastropod taxon is very low-spired, widely phaneromphalous, has a selenizone slightly above the periphery of the whorls and a dominant spiral ornament. It belongs to the superfamily Pleurotomarioidea and its knowledge improves our understanding of the Middle and Late Triassic radiation of this group.