Natura - nature
  
 actualia - actual entities
    
 Mundus Plinius - physical world
      
 naturalia - natural bodies
        
 Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
          
 Clade neomura Cavalier-Smith, 1987
            
 Domain Eukaryota Chatton, 1925 - eukaryotes
              
 Clade discaria Cavalier-Smith, 2021
                
 Clade natates Cavalier-Smith, 2021
                  
 Clade photaria Cavalier-Smith, 2021
                    
 Clade eucorta Cavalier-Smith, 2021
                      
 Superkingdom Corticata Lankester, 1878 - corticates
                        
 Kingdom Chromista Caval.-Sm. (1981) - chromists
                          
 Subkingdom Harosa Cavalier-Smith, 2010
                            
 Clade Sar Adl et al. 2012 [Simpson & Dunthorn 2020]
                              
 Infrakingdom Halvaria Cavalier-Smith, 2010
                                
 Superphylum Heterokonta Caval.-Sm. (1986)
                                  
 Phylum Bigyra Cavalier-Smith, 1998
                                    
 Subphylum Opalozoa Cavalier-Smith, 1992
                                      
 Infraphylum Placidozoa Cavalier-Smith, 2013
                                        
 Superclass Opalinata Wenyon, 1926
                                          
 Class Opalineaᵀ Wenyon, 1926
                                            
 Order Opalinidaᵀ Poche, 1913
                                              
 Family Opalinidaeᵀ Claus, 1874
                                                
 [Genus Bezzenbergeria Earl, 1973]