Chloe Kim #1 of the United States competes in the FIS World Cup 2018 Ladies Snowboard Halfpipe final during the Toyota U.S. Grand Prix on December 9, 2017 in Copper Mountain, Colorado. Matthew StockmanâGetty Images.
The phylum name Platyhelminthes literally means flatworms.. Members of this phylum are soft, thin-bodied, leaf or ribbonlike worms, including the familiar planaria of ponds and streams, as well as the flukes and tapeworms parasitic in human and other animal bodies.
Hence, the traditional platyhelminth subgroup Turbellaria is now regarded as paraphyletic, since it excludes the wholly parasitic groups, although these are descended from one group of turbellarians. Over half of all known flatworm species are parasitic, and some do enormous harm to humans and their livestock.Schistosomiasis, caused by one genus of trematodes, is the second-most devastating of all human diseases caused by parasites, surpassed only by malaria.rom Wikipedia, the free encyclopedia. The flatworms, or Platyhelminthes, Plathelminthes, or platyhelminths (from the Greek ÏÎ»Î±ÏÏ, platy, meaning flat and á¼Î»Î¼Î¹Î½Ï (root: á¼Î»Î¼Î¹Î½Î¸-), helminth- , meaning worm) are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates.