WebDec 8, 2024 · Terrestrial flatworms vary in size, from just a few millimeters to over one foot (12”) long. Although they can stretch and contract easily, they come in a few general shapes. Some are wider in the middle and … Webfluke, also called blood fluke or trematode, any member of the invertebrate class Trematoda (phylum Platyhelminthes), a group of parasitic flatworms that probably evolved from free-living forms millions of years ago. There …

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WebJul 21, 2024 · Flatworm. Definition. noun, plural: flatworms. Any of the worms (e.g. tapeworms, trematodes, planarians, etc .) belonging to the phylum Platyhelminthes, … ezel uraz sanovel

Planarian - Wikipedia

WebAcoela, or the acoels, is an order of small and simple invertebrates in the subphylum Acoelomorpha of phylum Xenacoelomorpha, a deep branching bilaterian group of animals, which resemble flatworms. Historically they were treated as an order of turbellarian flatworms. [1] [2] The etymology of "acoel" is from the Ancient Greek words ἀ ( a ... Early classification divided the flatworms in four groups: Turbellaria, Trematoda, Monogenea and Cestoda. This classification had long been recognized to be artificial, and in 1985, Ehlers proposed a phylogenetically more correct classification, where the massively polyphyletic "Turbellaria" was split into a dozen orders, and Trematoda, Monogenea and Cestoda were joined in the ne… flatworm, also called platyhelminth, any of the phylum Platyhelminthes, a group of soft-bodied, usually much flattened invertebrates. A number of flatworm species are free-living, but about 80 percent of all flatworms are parasitic—i.e., living on or in another organism and securing nourishment from it. They are … See more Most turbellarians are less than five millimetres (0.2 inch) long, and many are microscopic in size. The largest of this class are the planarians, which may reach 0.5 metre (about 20 … See more hibemate是什么