Use "rudist|rudists" in a sentence

1. In the Upper Aptian, the reef-forming Urgonian facies became established in both sub-basins—fossiliferous limestones composed of algae, coralline polyps, and rudists.

2. The most remarkable structures of these rudists are the two primary pillars and a lot of radially arranged secondary pillars in the right valve, corresponding with oscules in the left valve.Osculigera cleggiKühn,Osculigera sp. andOsculigera vautrinioides n. sp. are described.