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 Annelida Lamarck, 1809 - segmented worms
           Class Hirudinoidea see Class Clitellata Michaelsen, 1919
             Subclass Hirudinea see Subclass Euhirudinea Lukin, 1956
               Order Arhynchobdellae see Order Arhynchobdellida Blanchard, 1894
                 Family Erpobdellidae Blanchard, 1894
                   1 Genus Erpobdella Lamarck, 1818
                   2 ?Genus Trematobdella Johannson, 1928
                   3 ?Genus Foraminobdella
                   4 ?Genus Acrabdella Harding, 1931