[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Nematoidea
         [Class] Nematoidea Rudolphi, 1808 see Phylum Nematoda Gegenbaur, 1859
           [Family] Chætosomidæ nom. illeg.
             Genus Rhabdogaster Metschnikoff, 1867, nom. illeg. see Genus Epsilonema Steiner, 1927