life see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Empire Eukaryota (Chatton, 1925) see Domain Eukaryota Chatton, 1925
     Superkingdom Metakaryota see Domain Eukaryota Chatton, 1925
       Kingdom Protozoa Goldfuss, 1818 - protozoa
         Subkingdom Dictyozoa Cavalier-Smith, 1991
           Branch Bikonta Cavalier-Smith, 1993
             Infrakingdom Neozoa Cavalier-Smith, 1993
               Parvkingdom Alveolata Cavalier-Smith, 1991 see Superphylum Alveolata Cavalier-Smith, 1991
                 Superphylum Heterokaryota Hickson, 1903 [monotypic]
                   Phylum Ciliophora Doflein, 1901 - ciliates
                     Class Spirotrichea Bütschli, 1889
                       1 Subclass Heterotrichia (Stein, 1859) Cavalier-Smith, 1993
                       2 Subclass Choreotrichia Small & Lynn, 1985
                       3 Subclass Stichotrichia Small & Lynn, 1985