Sea urchin - Wikipedia
Sea urchin Temporal range: Ordovician–Present PreЄ Є O S D C P T J K Pg N Tripneustes ventricosus and Echinometra viridis Scientific classification Kingdom: Animalia Phylum: Echinodermata Subphylum: Echinozoa Class: Echinoidea Leske, 1778 Subclasses Subclass Perischoechinoidea Order Cidaroida (pencil urchins) Subclass …