Protozoa Goldfuss, 1818 - protozoans
   Phylum Ciliophora Doflein, 1901 - ciliates
     Class Kinetofragminophorea - kinetofragminophoreans see Phylum Ciliophora Doflein, 1901
       Subclass Hypostomatia - hypostome ciliates see Subphylum Intramacronucleata Lynn, 1996
         Order Apostomatida Chatton & Lwoff, 1928
         Order Chonotrichida Wallengren, 1895 see Subclass Chonotrichia Wallengren, 1895
         Order Cyrtophorida Fauré-Fremiet, 1956 see Class Phyllopharyngea de Puytorac et al., 1974
         Order Nassulida Jankowski, 1967
         Order Rhynchodida Chatton & Lwoff, 1939
         Order Synhymeniida de Puytorac et al., 1974