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
           1 Superorder Diadematacea (Duncan, 1889)
           2 Superorder Echinacea Claus, 1876
           3 Superorder Gnathostomata Zittel, 1879
           4 Superorder Atelostomata von Zittel, 1879 - irregular urchins