Gatunek typowy
Hayamia rex Kase in Kase & Maeda, 1980; Late Cretaceous, Japan

Opis

Shell large-sized and relatively thin conch with its height almost equal to width and more or less protruded spire; surface sculptured by numerous and more or less irregularly spaced spiral threads, in some species also by costellae; inner lip long narrow and concave without a notch behind. No parietal tubercle; operculum of naticopsid type, elliptical, lacking a quadrangular process at adaxial edge.

Synonimy

Zasięg czasowy

Jurassic to Cretaceous.

Literatura

Kase, T. & Maeda, H. 1980. Early Cretaceous Gastropoda from the Choshi District, Chiba Prefecture, Central Japan. Transactions and Proceedings of the Palaeontological Society of Japan,118, 291–324.