List of parasitic organisms

This is an incomplete list of organisms that are true parasites upon other organisms. For information on parasitoids, see main article: Parasitoid.

(endo = within; parasites that live inside their hosts)

These can be categorized into three groups; cestodes, nematodes and trematodes. Examples include:

(ecto = outside; parasites that live on but not within their hosts, for example, attached to their skin)

Monogeneans are flatworms, generally ectoparasites on fish.

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