[Class] Polycystinea Ehrenberg, 1838 - polycystines see Superclass Polycystinia Ehrenberg, 1838
   Order Nassellaria Ehrenberg, 1875 see Class Nassellaria Ehrenberg, 1847
     Family Theoperidae Haeckel, 1881
       Genus Eucecryphalus Haeckel, 1860
         1 Eucecryphalus cervus (Ehrenberg, 1872)
         2 Eucecryphalus clinatus Takahashi, 1991
         3 Eucecryphalus craspedota (Jørgensen, 1900)
         4 †Eucecryphalus emmae (Haeckel, 1887)
         5 Eucecryphalus europae (Haeckel, 1887)
         6 Eucecryphalus gegenbauri Haeckel, 1860
         7 †Eucecryphalus petrushevskaae Caulet, 1979
         8 Eucecryphalus sestrodiscus (Haeckel, 1887)
         9 Eucecryphalus tricostatus (Haeckel, 1887)