Kingdom Animalia Linnaeus, 1758 - animals Phylum Platyhelminthes Gegenbaur, 1859 - flatworms Class Monogenea Carus, 1863 - monogeneans see Infraclass Monogenea Subclass Monopisthocotylea Genus Gyrodactylus Nordmann, 1832 Genus Polystoma Zeder, 1800