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 Sarcomastigophora Honigberg & Balamuth, 1963
           Subphylum Opalinata Wenyon, 1926 see Superclass Opalinata Wenyon, 1926
             Order Opalinida Poche, 1913
               Family Opalinidae Claus, 1874
                 Genus Protoopalina Metcalf, 1918