Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Chaetognatha Leuckart, 1854 - chaetognaths
     Order Phragmophora Cooper, 1955 see Order Biphragmophora Casanova, 1985
       Family Eukrohniidae Tokioka, 1965
         1 Genus Bathyspadella Tokioka, 1939
         2 Genus Eukrohnia Ritter-Záhony, 1909
         3 Genus Heterokrohnia Ritter-Záhony, 1911
         4 Genus Kukrohnia