Sea Daisies: Concentricycloidea

Sea daisies are small, circular animals related to sea stars. There are only two species. Sea daisies have no arms, but the circle is rimmed with flat spines that look like daisy petals. The upper surface of the animal is delicately plated. The bottom surface has a mouth frame that leads to a shallow stomach and has a single ring of tube feet. Sea daisies are 0.4 to 0.6 inches (10 to 14 millimeters) across. They are see-through but not clear, like fogged-up glass. These animals have a water circulation system arranged in rings. The sexes are separate.