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
                                        
 Clade Ambulacraria Metschnikoff 1881 [Halanych 1995]
                                          
 Phylum Echinodermata Bruguière, 1789 - echinoderms
                                            
 Subphylum Eleutherozoa Bell, 1891
                                              
 Infraphylum Echinozoa Haeckel, in Von Zittell, 1895
                                                
 Class Echinoidea (Leske, 1778) - sea urchins and sand dollars
                                                  
 Subclass Perischoechinoidea (M'Coy, 1849)
                                                    
 Order Cidaroida Claus, 1880
                                                      
 Family Cidaridaeᵀ Gray, 1825
                                                        
 Genus Cidarisᵀ Leske, 1778
                                                        
 Genus Ctenocidaris Mortensen, 1910
                                                        
 Genus Poriocidaris Mortensen, 1909
                                                        
 Genus Stereocidaris Pomel, 1883
                                                        
 Genus Stylocidaris Mortensen, 1909