living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Protozoa Goldfuss, 1818 see Kingdom Protozoa Goldfuss, 1818
         Phylum Ciliophora Doflein, 1901 - ciliates
           Class Polyhymenophora Jankowski, 1967 see Class Spirotrichea Bütschli, 1889
             Subclass Spirotricha see Class Spirotrichea Bütschli, 1889
               Order Hypotrichida Stein, 1859 - hypotrichs see Subclass Hypotrichia (Stein, 1859) Cavalier-Smith, 1993
                 Suborder Stichotrichina Fauré-Fremiet, 1961 see Order Stichotrichida Fauré-Fremiet, 1961
                   1 Family Spirofilidae von Gelei, 1929
                   2 Family Strongylidiidae Fauré-Fremiet, 1961
                   3 Family Urostylidae Bütschli, 1889
                   4 Family Holostichidae Fauré-Fremiet, 1961 see Family Urostylidae Bütschli, 1889
                   5 Family Psilotrichidae Bütschli, 1889
                   6 Family Kiitrichidae Nozawa, 1941
                   7 Family Keronidae Dujardin, 1840