fossil marine animal genera Linnaeus, 1758 - animals
   Phylum Echinodermata Bruguière, 1789 - echinoderms
     Class Echinoidea (Leske, 1778) - sea urchins and sand dollars
       01 Order †Bothriocidaroida von Zittel, 1879
       02 Order †Echinocystitoida Jackson, 1912
       03 Order Cidaroida Claus, 1880
       04 Order Echinothurioida Claus, 1880
       05 Order Diadematoida Duncan, 1889
       06 Order Pedinoida Mortensen, 1939
       07 Order †Pygasteroida Durham & Melville, 1957
       08 Order Salenioida Delage & Herouard, 1903
       09 Order †Hemicidaroida (Beurlen, 1937)
       10 Order Phymosomatoida Mortensen, 1904
       11 Order Temnopleuroida (Mortensen, 1942)
       12 Order Echinoida Troschel, 1872
       13 Order †Plesiocidaroida Duncan, 1889
       14 Order †Orthopsida (Mortensen, 1942)
       15 Order Holectypoida Ducan, 1889
       16 Order †Oligopygoida
       17 Order Clypeasteroida A. Agassiz, 1872 - true sand dollars
       18 Order Cassiduloida Claus, 1880
       19 Order †Disasteroida
       20 Order Holasteroida Durham & Melville, 1957 see Suborder Holasterina
       21 Order Spatangoida L. Agassiz, 1840
       22 Order Neolampadoida
       23 Order †uncertain