Echinodermata is a phylum of marine animals including starfish, sea urchins, sand dollars, and sea cucumbers. They usually have radial symmetry. Crinoids are also chinoderms, and are very common in during some periods in the fossil record.
Echinodermata is a phylum of marine animals including starfish, sea urchins, sand dollars, and sea cucumbers. They usually have radial symmetry. Crinoids are also chinoderms, and are very common in during some periods in the fossil record.