The term sand dollar (or sea cookie or snapper biscuit in New Zealand, or pansy shell in South Africa) are species of extremely flattened, burrowing sea urchins belonging to the order Clypeasteroida. Some species within the order, not quite as flat, are known as sea biscuits. Related animals include other sea urchins, sea cucumbers and starfish.

The term sand dollar (or sea cookie or snapper biscuit in New Zealand, or pansy shell in South Africa) are species of extremely flattened, burrowing sea urchins belonging to the order Clypeasteroida. Some species within the order, not quite as flat, are known as sea biscuits. Related animals include other sea urchins, sea cucumbers and starfish.