@lioness
Hi,
Yes mussels are shellfish....crustaceans and mollusks(like clams) are both types of shellfish so you can’t have either if you are allergic. I think octopus and squid are considered shellfish but not sure about that. I’d Goggle any type of caned fish (there are canned mussels and oysters) if you were to go shopping and were thinking of buying a can. Smoked oysters are good canned but you can’t have them.

Mary