The short-spined sea urchin is commonly found along inshore shallow water areas and sandy bottoms. They have short spines, and can adorn themselves with debris to provide protection from predators. Flat-clawed hermits live from sub-tidal areas to the low tide line along the Atlantic coast. They are unusual because they are not striped like most hermit crabs. They are a pale off-white color, and have two unequal in size flat claws that lock together to form an operculum when the crab withdraws from its shell.
Next time you walk by the touch tank, make sure to stop by and ask a volunteer to point out the new inhabitants!