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 Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Echinodermata Bruguière, 1789 - echinoderms
           Subphylum Echinozoa von Zittel, 1895 see Infraphylum Echinozoa Haeckel, in Von Zittell, 1895
             Class Holothuroidea (de Blainville, 1834) - sea cucumbers
               Subclass Apodacea
                 Order Apodida Brandt, 1835
                   Family Synaptidae Burmeister, 1837
                     1 Genus Synaptula Örsted, 1849
                     2 Genus Protankyra Östergren, 1898
                     3 Genus Leptosynapta Verrill, 1867
                     4 Genus Polyplectana Clark, 1907
                     5 Genus Euapta Oestergren, 1898