Kingdom Animalia Linnaeus, 1758 - animals
Phylum Echinodermata Bruguière, 1789 - echinoderms
Subphylum Echinozoa von Zittel, 1895
see Infraphylum Echinozoa Haeckel, in Von Zittell, 1895
Class Echinoidea (Leske, 1778) - sea urchins and sand dollars
Genus Arbacia Gray, 1835
Genus †Diademopsis Desor, 1858[1855]
Genus Echinometra Meuschen, 1778
Genus †Echinotiara Pomel, 1883
Genus Echinus Linnaeus, 1758
Genus Eucidaris Pomel, 1883
Genus Heterocentrotus Brandt, 1835
Genus †Pentedium Kier, 1967
Genus †Plesiechinus Pomel, 1883
Genus Psammechinus Agassiz, 1846
Genus †Pseudocidaris Etallon, 1862
Genus Spatangus Gray, 1825
Genus Strongylocentrotus Brandt, 1835
1 Order †Echinocystitoida Jackson, 1912
2 Order †Palaechinoida
3 Order Cidaroida Claus, 1880
4 Order Cassiduloida Claus, 1880
5 Order Spatangoida L. Agassiz, 1840
6 Order Clypeasteroida A. Agassiz, 1872 - true sand dollars