New genus and new species of Echinoid (Echinodermata, Orthopsidae) from the Albian (Lower Cretaceous) of Sergipe-Alagoas Basin, Brazil

Résumé

Cuscuzispina riachuelensis n.gen. and n.sp. is described from the lower Cretaceous (Albian) Riachuelo Formation, Sergipe Sub-Basin, Northeastern Brazil. Although somewhat similar to another Cretaceous echinoid Orthopsis, C. riachuelensis differs from that genus in its highest test, by the presence of interambulacral depressions, the width of the ambulacral plates near the apical system, and shape of the genital plates. Cuscuzispina’s morphology suggests that this echinoid lived in a protected shallow-water environment, with stabilized sedimentary substrata where it was a grazing feeder.