List of parasitic organisms

This is an incomplete list of organisms that are true parasites upon other organisms.

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

Plants

 * Rafflesia
 * Cuscuta
 * Mistletoe

Parasitic worms
These can be categorized into three groups; cestodes, nematodes and trematodes. Examples include:
 * Acanthocephala
 * Ascariasis (roundworms)
 * Cestoda (tapeworms) including: Taenia saginata (human beef tapeworm), Taenia solium (human pork tapeworm), Diphyllobothrium latum (fish tapeworm) and Echinococcosis (hydatid tapeworm)
 * Clonorchis sinensis (the Chinese liver fluke)
 * Dracunculus medinensis (Guinea worm)
 * Enterobius vermicularis (pinworm)
 * Filariasis
 * Hookworm
 * Loa loa
 * Onchocerciasis (river blindness)
 * Schistosomiasis
 * Strongyloides stercoralis
 * Tapeworm
 * Toxocara canis (dog roundworm)
 * Trichinella
 * Whipworm

Protozoans

 * Entamoeba histolytica and Entamoeba coli - can cause Amoebiasis
 * Acanthamoeba
 * Balamuthia mandrillaris
 * Giardia
 * Cyclospora cayetanensis
 * Cryptosporidium
 * Toxoplasma gondii
 * Leishmania - L. tropica, L. donovani, and L. mexicana are known to cause Leishmaniasis.
 * Plasmodium - causes the fatal disease, Malaria. P. falciparum, P. vivax, and P. malariae are pathogenic to humans.
 * Babesia

Fungi

 * Gymnosporangium and other rusts
 * Pyrenophora teres
 * Cordyceps

Arthropods

 * Pentastomida

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

Arthropoda

 * Acari
 * Varroa destructor
 * Cymothoa exigua
 * Bed bugs
 * Culicidae (mosquitoes)
 * Calyptra (moth) (vampire moths)
 * Hippoboscoidea
 * Tsetse fly
 * Lipoptena
 * Melophagus ovinus, (sheep keds) and relatives
 * Oestridae (bot flies)
 * Human botfly
 * Cuterebra fontinella (mouse botfly)
 * Phlebotominae (sand flies)
 * Phthiraptera (Lice)
 * Body louse
 * Crab louse
 * Head louse
 * Siphonaptera (fleas)
 * Tabanidae (horse flies)
 * Tantulocarida
 * Triatominae
 * Pea crab
 * Sacculina

Annelids

 * Hirudinea (some leeches)

Monogeneans
Monogeneans are flatworms, generally ectoparasites on fish.
 * Calydiscoides euzeti
 * Lethacotyle vera
 * Protocotyle euzetmaillardi
 * Pseudorhabdosynochus spp.

Mollusks

 * Cancellaria cooperii
 * Glochidium
 * Pyramidellidae
 * †Platyceratidae

Chordates

 * Cookiecutter shark
 * Candiru (vampire fish of Brazil, a facultative parasite)
 * Lampreys
 * Male Deep sea anglers
 * False cleanerfish
 * Hood mockingbird
 * Oxpeckers (cleaning symbiosis)
 * Snubnosed eel
 * Vampire bat
 * Vampire finch
 * Cuckoo (brood parasite)
 * Cowbird (brood parasite)

Plants

 * Mistletoe
 * Monotropa uniflora
 * Certain orchids
 * Nuytsia
 * Orobanche (broomrape)
 * Santalum album
 * Certain plants with albinism

Fungi

 * Corn smut
 * Certain mushrooms
 * Asterotremella albida