Eastern oyster

Crassostrea virginica

Family Ostreidae - oysters

Bivalve (2 shells); shell usually oval, possibly wider at the unhinged end, thick, irregular, sometimes with concentric rings, shell can be scaly, can grow to any shape necessary; shell color usually gray, can have greenish or reddish tinge due to algae; can have many encrusting organisms on shell, including spat (larval oysters); usually attaches to other oysters to build reefs but can attach to any hard surface; beaks long, sometimes curve; upper valve shorter, flatter and smoother than lower valve; hinge attachment sight usually out of sight in between both valves; inside smooth, white with purple muscle scar.
Similar Species
The eastern oyster is most similar to the crested oyster. It is smaller (maximum size about 51 cm or 2 in), round, and resides in more saline water than the eastern oyster. The main distinction is that crested oysters have teeth on the upper interior lateral margins (absent in eastern oysters) and colorless muscle scars.
Bay, usually occur as reefs
Maximum Size
22 cm (8 3/4 in)
Other Common Names
Previous Scientific Names