Phylum Nematoda Gegenbaur, 1859 - round worms
   Class Secernentea Von Linstow, 1905
     Subclass Tylenchia (Thorne, 1949) Inglis, 1983
       Order Tylenchida G. Thorne, 1949
         Suborder Hexatylina Siddiqi, 1980
           Superfamily Sphaerularioidea Lubbock, 1861
             1 Family Neotylenchidae Thorne, 1941
             2 Family Sphaerulariidae Lubbock, 1861
             3 Family Paurodontidae Thorne, 1949, nom. illeg., nom. dub.
             4 Family Allantonematidae Pereira, 1931