life see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Empire Eukaryota (Chatton, 1925) see Domain Eukaryota Chatton, 1925
     Kingdom Chromista Caval.-Sm. (1981) - chromists
       Subkingdom Chromobiota Caval.-Sm. (1991)
         Infrakingdom Heterokonta Caval.-Sm. (1986) - heterokonts see Superphylum Heterokonta Caval.-Sm. (1986)
           Superphylum Gyrista Caval.-Sm. (1998)
             Phylum Bigyra Caval.-Sm. (1998) see Phylum Bigyra Cavalier-Smith, 1998
               Subphylum Opalinata Earl (1971) see Superclass Opalinata Wenyon, 1926
                 Class Opalinea Wenyon (1926) see Class Opalinea Wenyon, 1926
                   Order Opalinida Poche, 1913