Rudists
| Rudists Temporal range: | |
|---|---|
| Rudist bivalves from the Cretaceous of the Oman Mountains, United Arab Emirates; scale bar is 10 mm. | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Infraclass: | Heteroconchia |
| Subterclass: | Euheterodonta |
| Superorder: | Imparidentia |
| Order: | †Hippuritida |
| Families | |
|
See text | |
Rudists are a group of extinct box-, tube- or ring-shaped marine heterodont bivalves belonging to the order Hippuritida that arose during the Late Jurassic and became so diverse during the Cretaceous that they were major reef-building organisms in the Tethys Ocean, until their complete extinction at the close of the Cretaceous.