Kingdom Animalia Linnaeus, 1758 - animals Phylum Echinodermata Bruguière, 1789 - echinoderms Subphylum Eleutherozoa Bell, 1891 Class Echinoidea (Leske, 1778) - sea urchins and sand dollars Subclass Euechinoidea Bronn, 1860 Superorder Diadematacea (Duncan, 1889) Genus Diadema Gray, 1825, nom. cons.