[Class] Polycystinea Ehrenberg, 1838 - polycystines see Superclass Polycystinia Ehrenberg, 1838
   Order Nassellaria Ehrenberg, 1875 see Class Nassellaria Ehrenberg, 1847
     Family Pterocorythidae Haeckel, 1881 see Family Pterocoryidae Haeckel, 1881
       Genus Theocorythium Haeckel, 1887
         1 Theocorythium trachelium (Ehrenberg, 1872)
         2 †Theocorythium vetulum Nigrini, 1971