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 Asterozoa von Zittel, 1895 see Infraphylum Asterozoa von Zittel, 1895
             Class Stelleroidea Lamarck, 1816 see Subphylum Asterozoa von Zittel, 1895
               Subclass Ophiuroidea Gray, 1840 - brittle stars see Class Ophiuroidea Gray, 1840
                 Order Ophiurida Müller & Troschel, 1840 sensu O'Hara et al., 2017 sensu O'Hara & al. , 2017
                   Suborder Gnathophiurina Matsumoto, 1915 see Order Ophiurida Müller & Troschel, 1840 sensu O'Hara et al., 2017 sensu O'Hara & al. , 2017
                     Family Ophiactidae Matsumoto, 1915
                       1 Genus Ophiactis Lütken, 1856
                       2 Genus Hemipholis Lyman, 1865
                       3 Genus Ophiodaphne Koehler, 1931
                       4 Genus Ophiopholis Müller & Troschel, 1840
                       5 Genus Ophiopus Ljungman, 1866