| Biotic Setting | Benthic/Attached Biota |
| Biotic Class | Reef Biota |
| Biotic Subclass | Mollusk Reef Biota |
| Biotic Group | Oyster Reef |
| Biotic Community | Crassostrea Reef Ostrea Reef |
| Definition | Areas dominated by the ridge- or mound-like structures formed by the colonization and growth of oysters that are attached (cemented) to a substrate of live and dead conspecifics. Oyster reefs provide excellent structural habitat as well as effective water filtration. |