First fossil records of cephalopod statoliths

Abstract

THE class Cephalopoda is represented by over 10,000 fossil species and about 1,000 living species. Almost the entire fossil record so far described consists of external or internal calcareous shells of the Ammonoidea, the Nautiloidea and some members of the Coleoidea. The subclass Coleoidea includes all but three (Nautilus spp.) of the living species of cephalopods, and is represented in the fossil record largely by the order Belemnitida which is important from the early Jurassic to the Eocene. Another coleoid order, the Sepioidea, including the living Sepia and Spirula have internal calcareous shells, and have left traces from the Upper Jurassic (Voltzia) to the present. The three remaining coleoid orders, the Teuthoidea, the Vampyromorpha and the Octopodida include all the remaining living cephalopods, comprising 29 teuthoid or squid families, one vampyromorph family and 12 octopod families.