This colorful sea cucumber is a member of the phylum known as echinoderms. This is the same group that includes starfish and sea urchins. Sea cucumbers get their name from their elongated, rough shape that resembles a cucumber. They can be found on the sea floor worldwide, with over 1,700 known species. They have tentacles on one end of their bodies that they use to sift the sand on the sea floor. They are filter feeders, filtering bits of food from the sand. They range in size from 3 inches (7 cm) to just over 12 inches (30 cm) in length.