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 Oligohymenophora see Class Oligohymenophorea de Puytorac et al., 1974
             Subclass Peritricha Stein, 1859 - peritrichs see Subclass Peritrichia Stein, 1859
               Order Peritrichida Stein, 1859 see Subclass Peritrichia Stein, 1859
                 Suborder Sessilina Kahl, 1933 see Order Sessilida Kahl, 1933
                   01 Family Vorticellidae Ehrenberg, 1838
                   02 Family Astylozoidae Kahl, 1935
                   03 Family Epistylididae Kahl, 1933
                   04 Family Operculariidae Fauré-Fremiet, in Corliss, 1979
                   05 Family Opisthonectidae Foissner, 1976
                   06 Family Scyphidiidae Kahl, 1933
                   07 Family Ophrydiidae Ehrenberg, 1838
                   08 Family Ellobiophryidae Chatton & Lwoff, 1923
                   09 Family Termitophryidae Lom, in Corliss, 1979
                   10 Family Rovinjellidae Matthes, 1972
                   11 Family Vaginicolidae de Fromentel, 1874
                   12 Family Lagenophryidae Bütschli, 1889