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 dorsates Cavalier-Smith, 2021
                  
 Clade podiates Cavalier-Smith, 2012
                    
 Clade Amorphea Adl et al. 2012 [Simpson, Medina & Adl 2020]
                      
 Clade Obazoa Brown, Sharpe, Silberman, Heiss, Lang, Simpson & Roger 2013
                        
 Clade Opisthokonta Cavalier-Smith 1987 [Simpson & Medina 2020] - animal-fungal clade
                          
 Superkingdom Holozoa Lang, O'Kelly, Nerad, Gray & Burger, 2002
                            
 Clade filozoa Shalchian-Tabrizi, Minge, Espelund, Orr, Ruden, Jakobsen & Cavalier-Smith, 2008
                              
 Kingdom Animalia Linnaeus, 1758 - animals
                                
 Clade Planulozoa Wallberg, Thollesson, Farris & Jondelius 2004
                                  
 Subkingdom Bilateria Hatschek, 1888 - bilaterians
                                    
 Clade Nephrozoa Jondelius, Ruiz-Trillo, Baguñà & Riutort 2002
                                      
 Infrakingdom Deuterostomia Grobben, 1908
                                        
 Phylum Chordata Bateson, 1885 - chordates
                                          
 Subphylum Craniata auct.
                                            
 Infraphylum Vertebrata Lamarck, 1801 - vertebrates
                                              
 Clade Pan-Gnathostomata Downs 2020
                                                
 Superclass Gnathostomataᵀ Gegenbaur, 1874 - jawed vertebrates
                                                  
 [stem] Class †Placodermi McCoy, 1848 [paraphyletic]
                                                    
 Clade †Arthrodira Woodward, 1891
                                                      
 Order †Phlyctaeniiformes
                                                        
 Suborder †Brachythoraci Gross, 1932
                                                          
 Clade †Eubrachythoraci Miles, 1971, sedis mutabilis
                                                            
 Clade †Pachyosteomorphi Stensiö, 1944 [paraphyletic] - pachyosteomorphs
                                                              
 Clade †Aspinothoracidi Stensiö, 1959
                                                                
 Family †Selenosteidae Dean, 1901
                                                                  
 1 Genus †Gymnotrachelus Dunkle & Bungart, 1939, sedis mutabilis [monotypic]
                                                                  
 2 Genus †Pachyosteus Jaekel, 1903, sedis mutabilis
                                                                  
 3 Genus †Stenosteus Dean, 1901, sedis mutabilis
                                                                  
 4.1.1 Genus †Selenosteusᵀ Dean, 1901
                                                                  
 4.1.2.1 Genus †Walterosteus Stensiö, 1959
                                                                  
 4.1.2.2.1 Genus †Enseosteus Jaekel, 1919
                                                                  
 4.1.2.2.2 Genus †Draconichthys Rücklin, 2011
                                                                  
 4.2.1 Genus †Rhinosteus Jaekel, 1911
                                                                  
 4.2.2.1 Genus †Melanosteus Lelièvre & Goujet, 1987
                                                                  
 4.2.2.2.1 Genus †Driscollaspis Rücklin, Long & Trinajstic, 2015 [monotypic]
                                                                  
 4.2.2.2.2 Genus †Brachyosteus Jaekel, 1927