Lithomphalus enderlini gen. et sp. nov. from cold-seep carbonates in California—a Cretaceous neomphalid gastropod?

The new genus and species Lithomphalus enderlini is described from two Early Cretaceous (Valanginian) suspected cold-seep carbonates in western California, USA. These carbonates were found within turbidites of the Great Valley Group, and were deposited at slope depth. Considering its shell shape and its crossed-lamellar shell structure, this species might belong to the enigmatic vent and seep endemic gastropod group Neomphaloidea. It cannot be assigned with certainty to any of the extant neomphaloidean families, and thus may represent an independent Mesozoic radiation of the Neomphalina. However, until additional and better-preserved specimens are discovered (e.g., those with protoconchs), caution is advised with regard to verifying the earliest occurrence of the Neomphalidea in the fossil record.