Class Maxillopoda Dahl, 1956 see Subphylum Pancrustacea Zrzavý et al., 1997
   Subclass †Halicyna Gall & Grauvogel, 1967 see Subclass Branchiura Thorell, 1864
     Order †Cycloidea Schram, Vonk & Hof, 1997 - cycloids see Order Cyclida Schram, Vonk & Hof, 1997, nom. corr.
       Family †Cyclidae Packard, 1885
         Genus †Cyclus de Koninck, 1841
           1 †Cyclus radialis (Phillips, 1835)
           2 †Cyclus brongniartianus de Koninck, 1842
           3 †Cyclus americanus Packard, 1885 see Americlus americanus (Packard, 1885)
           4 †Cyclus obesus Schram, Vonk & Hof, 1997 see Americlus obesus (Schram, Vonk & Hof, 1997)