Nemathelminthes Gegenbaur, 1859 see Phylum Nematoda Gegenbaur, 1859
   Class Nematoda Gegenbaur, 1859
     Subclass Penetrantia
       Order Dorylaimida Pearse, 1942
         Suborder Dorylaimina Chitwood, 1933
           Family Leptonchidae Thorne, 1935
             Genus Dorylaimoides G. Thorne & H.H. Swanger, 1936
             Genus Doryllium Cobb, 1920
             Genus Leptonchus Cobb, 1920
             Genus Tylencholaimellus Cobb, in M.V. Cobb, 1915