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 Kinetofragminophora see Class Kinetofragminophorea
             Subclass Hypostomata Schewiakoff, 1896 see Subclass Hypostomatia
               Order Apostomatida Chatton & Lwoff, 1928
                 Suborder Apostomatina Chatton & Lwoff, 1928 see Order Apostomatida Chatton & Lwoff, 1928
                   Family Foettingeriidae Chatton, 1911
                     1 Genus Foettingeria Caullery & Mesnil, 1903
                     2 Genus Gymnodinioides Minkiewicz, 1912
                     3 Genus Hyalophysa Bradbury, 1966
                     4 Genus Polyspira Minkiewicz, 1912
                     5 Genus Spirophrya Chatton & Lwoff, 1924
                     6 Genus Terebrospira Debaisieux, 1960