(also rudistid /ˈro͞odistid/)
A cone-shaped extinct bivalve mollusk that formed colonies resembling reefs in the Cretaceous period.
- Superfamily Rudistacea, order Hippuritoida
More example sentences
- An extinct group of Mesozoic bivalves, the rudistids, became closely adapted to a cemented mode of life: one valve became conical while the other formed a lid.
- Cretaceous radiations of rudists were apparently initiated during periods of globally high sea level and the Lebanon decapod faunas are a part of this general increasing invertebrate diversity.
- This member contains abundant and diverse mid-Cretaceous shallow-marine invertebrates, including reef corals and rudist bivalves.
Definition of rudist in:
- The British & World English dictionary