How many worms are adapted to a parasitic lifestyle?

There are thousands of worm species that have adapted to a parasitic lifestyle, primarily within the phyla Platyhelminthes (flatworms) and Nematoda (roundworms). Notable examples include tapeworms, flukes, and various nematodes that infect a wide range of hosts, including humans, animals, and plants. These parasitic worms have evolved specialized structures and life cycles that enable them to thrive within their hosts. Overall, the exact number of parasitic worm species is difficult to determine due to ongoing discoveries and classifications in Biology.