What’s the difference between clams, mussels, and oysters?

Written by

Manjishtha Bhattacharyya

Fact-checked by

Britannica Editors

Last updated

Nov. 6, 2026 •History

Although they are frequent neighbors on market ice and easily confused because of the similarity in their appearance, these three shellfish are as distinct from one another as cats, civets, and genets. They all belong to the same molluscan class—Bivalvia—but differ when it comes to where they live, what they look like up close, and how they interact with their environment. Before diving into the details of what sets each animal apart, let us first...