[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Platyelmia
         Branch Suctoria
           Class Trematoidea
             Order Digenea Carus, 1863
               1 Genus Distoma Retzius, 1786
               2 Genus Monostoma Zeder, 1800