[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Phylum Echinodermata Bruguière, 1789 - echinoderms
     Class Echinoidea (Leske, 1778) - sea urchins and sand dollars
       Order Diadematoida Duncan, 1889
         1 Family Aspidodiadematidae Duncan, 1889
         2 Family Diadematidae Gray, 1855