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 Nemertea Schultze, 1851 - ribbon worms
           Class Anopla see Phylum Nemertea Schultze, 1851
             Order Heteronemertea
               Family Baseodiscidae
                 1 Genus Oxypolella Bergendal, 1902
                 2 Genus Parapolia Coe, 1895
                 3 Genus Baseodiscus Diesing, 1850
                 4 Genus Oxypolia Punnett, 1901
                 5 Genus Cephalomastax Iwata, 1957