Echinoderms (Sea Stars, Sea Urchins, Sand Dollars, Sea Cucumbers) General Stuff Echinoderms belong to the Phylum Echinodermata, meaning “hedgehog skin”. Echinoderms have spiny skins. They have radial symmetry. They lack body segmentation. There are more than 5000 species of Echinoderms.
(Sea Stars, Sea Urchins, Sand Dollars, Sea Cucumbers)