If you’ve ever been to an ocean, you’ve probably seen sand dollars on the beach or in souvenir shops. You may have even seen live sand dollars moving around on the sandy ocean floor. But what exactly are these creatures?

Sand dollars — sometimes called sea cookies, snapper biscuits, sand cakes, cake urchins or pansy shells — are species of flat, burrowing echinoids that belong to the order Clypeasteroida. Sand dollars are related to sea urchins, sea cucumbers and starfish.


When sand dollars are alive, they live in shallow coastal waters along the sandy ocean floor. Unlike the white color of dead sand dollars, live sand dollars are usually green, purple or blue. Some people think live sand dollars look like fuzzy cookies!

Live sand dollars are covered with a dense, velvety layer of short spines and tubular feet. They use these spines and tubular feet to burrow into the sand and move around.


You may have noticed that sand dollar skeletons feature a pattern that looks like a flower. This pattern is where the live sand dollar’s tubular feet are located. In addition to helping the sand dollar move, these tubular feet also help direct food found on the ocean floor to the sand dollar’s mouth.

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