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 Astomatophorina Jankowski, 1966 see Order Astomatophorida Jankowski, 1966
                   Family Opalinopsidae Hartog, 1906
                     Genus Chromidina Gonder, 1905