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 Nemata Cobb, 1919 see Phylum Nematoda Gegenbaur, 1859
           Class Adenophorea
             Subclass Chromadoria Adamson, 1987
               Order Desmoscolecida Filipjev, 1929
                 Suborder Desmoscolecina Chitwood, 1933
                   Superfamily Greeffielloidea
                     Family Greeffiellidae
                       1 Genus Greeffiella Cobb, 1922
                       2 Genus Greeffiellopsis Schrage & Gerlach, 1975
                       3 Genus Progreeffiella
                       4 Genus Calligyrus Lorenzen, 1969
                       5 Genus Hapalomus Lorenzen, 1969