Shellfish is a term used to describe molluscs and crustaceans used as food. Molluscs include the clam, mussel, oyster, and scallop; some crustaceans are the shrimp, lobster, crayfish, and crab. Snails, while similar to most shellfish biologically, are generally not considered to be shellfish.

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Cooked mussels Shellfish is a term used to describe shelled molluscs a ...
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Resources

  • Shellfish (Centers for Disease Control and Prevention)