clam v. mussel v. oyster

Clams , mussels, and oysters are bivalve molluscs. Bivalves have hinged shells. Each half of the shell is known as a valve.

• Plastic boxes fashioned to look like a clam (top), oyster (left), and mussel (right). Image courtesy of Bellocchio.com. Clams have wide, round, roughly symmetrical, light to sandy brown shells. Mussel shells are long, narrow, and asymmetrical. They usually have darker blue, black, or brown coloration. While clam and mussel shells are smooth or evenly striated, oyster shells are rough and irregular. Oyster shells have one flat valve and one cupped valve.
• Clams are mobile, and can burrow in sand. Oysters & mussels are sedentary; they attach themselves to rocks or other hard surfaces.
• Different mussel and clam species live in marine and freshwater habitats. Oysters are only found in saltwater.
• Oysters are more likely to be eaten raw than clams or mussels.

Clovegarden.com on clams, oysters, mussels, and scallops