Class Crustacea Brünnich, 1772 - crustaceans see Superclass Crustacea Pennant, 1777
   Subclass Branchiura Thorell, 1864 - fish lice
     Order †Cyclida Schram, Vonk & Hof, 1997, nom. corr.
       01 Family †Cyclidae Packard, 1885
       02 Family †Schraminidae Dzik, 2008
       03 Genus †Apionicon Schram, Vonk & Hof, 1997
       04 Family †Americlidae Dzik, 2008
       05 Family †Hemitrochiscidae Trauth, 1918
       06 Genus †Oonocarcinus Gemmellaro, 1890
       07 Genus †Paraprosopon Gemmellaro, 1890
       08 Family †Halicynidae Gall & Grauvogel, 1967, nom. corr.
       09 Genus †Carcinaspides Glaessner, 1969
       10 Genus †Cyclocarcinides Glaessner, 1969
       11 Family †Mesoprosopidae Glaessner, 1928
       12 Genus †Juracyclus
       13 Genus †Stagmacaris Schweigert, 2006
       14 Genus †Maastrichtiocaris Fraaije, Schram & Vonk, 2003