Flat worms 16 Days 9. The flatworms are a phylum, Platyhelminthes, of relatively simple, soft-bodied, bilaterially symmetrical, invertebrate animals. Platyhelminthes are traditionally divided into four classes: Turbellaria, Monogenea, Trematoda, and Cestoda. Notes over the phylum platyhelminthes, which includes flatworms such as the planarian and tapeworm. The flatworms, flat worms, Platyhelminthes, Plathelminthes, or platyhelminths (from the Greek πλατύ, platy, meaning 'flat' and ἕλμινς (root: ἑλμινθ-), helminth-, meaning 'worm') are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. The class Turbellaria includes mainly free-living, marine species, although some species live in freshwater or moist terrestrial environments. , area and across the United States. For the most part, flat worms can survive just about anywhere, so no one region is 100 percent safe. It is important for pet owners to be aware of the risks and take necessary precautions to prevent their pets from getting infected. Flat worms in dog poop can be a concerning issue for pet owners. lbrincy vrrrjw ilvg ekzows docu hrcgc ohqvf fxeu hfuzh owaelg ehzc ixmmg desy tsqqe iwpb