Phylum Echinodermata Spiny Skin. Advanced? Skeleton is internal test comprised of individuals plates of porous high-Mg calcite. Bilaterally symmetrical.
Echinoderms. Phylum Echindermata Share common features with chordatesShare common features with chordates Radial CleavageRadial Cleavage Deuterostomes.
Phylum Echinodermata
Phylum Arthropoda
