endoparasitism

biology

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June 26, 2026

Quick Summary

Endoparasitism is a biological relationship where a parasite lives inside the internal organs or tissues of its host. This is a form of parasitism, a relationship between two species where one benefits at the expense of the other, sometimes without killing the host.12

Endoparasites can be further classified as intercellular, living in the spaces within the host's body, or intracellular, residing within the host's cells. Examples of endoparasitic organisms include protozoans, helminths (worms), and certain bacteria or viruses. These parasites often rely on carriers or vectors to transmit them to a host. Many parasitic diseases, such as malaria, amebic dysentery, and hookworm disease, are caused by endoparasites.234

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braconid wasp
Natural history and parasitism
Braconid larvae are either endoparasitic, living within their hosts, or ectoparasitic, living on their hosts. Endoparasitic adult females lay an egg or eggs in the larvae or eggs of the host (braconid wasps do not typically exploit adult hosts). Many species are egg-larval parasitoids, meaning the wasp eggs are…
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Braconid larvae are either endoparasitic, living within their hosts, or ectoparasitic, living on their hosts. Endoparasitic adult females lay an egg or eggs in the larvae or eggs of the host (braconid wasps do not typically exploit adult hosts). Many species are egg-larval parasitoids, meaning the wasp eggs are…
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parasitism
…disease in the host; or endoparasites, which may be either intercellular (inhabiting spaces in the host’s body) or intracellular (inhabiting cells in the host’s body). Intracellular parasites—such as bacteria or viruses—often rely on a third organism, known as the carrier, or vector, to transmit them to the host. Malaria, which…
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…disease in the host; or endoparasites, which may be either intercellular (inhabiting spaces in the host’s body) or intracellular (inhabiting cells in the host’s body). Intracellular parasites—such as bacteria or viruses—often rely on a third organism, known as the carrier, or vector, to transmit them to the host. Malaria, which…
Read More

plant disease
Nematode diseases
… species), cosmopolitan in distribution, are endoparasites that cause severe losses to hundreds of different crop and ornamental plants by penetrating roots and making their way through the tissues, breaking down the cells as they feed. They deposit eggs from which new colonies develop. After a root begins to decline in…
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… species), cosmopolitan in distribution, are endoparasites that cause severe losses to hundreds of different crop and ornamental plants by penetrating roots and making their way through the tissues, breaking down the cells as they feed. They deposit eggs from which new colonies develop. After a root begins to decline in…
Read More