Phylum Platyhelminthes Gegenbaur, 1859 - flatworms 1 Class Turbellaria Ehrenberg, 1831 - planarians see Subphylum Turbellaria Ehrenberg, 1831 2 Class Trematoda Rudolphi, 1808 - flukes see Infraclass Trematoda Rudolphi, 1808 3 Class Cestoda - tapeworms see Infraclass Cestoda