 | This articlemay incorporate text from alarge language model. It may includehallucinated information,copyright violations, claims notverified in cited sources,original research, orfictitious references. Any such material should beremoved, and content with anunencyclopedic tone should be rewritten.(September 2025) (Learn how and when to remove this message) |
Entozoa is an obsoletetaxonomic term that historically referred to a group ofparasitic animals that live inside the bodies of other organisms.[1] It was originally used in older classifications to describe a diverse assortment of internal parasites, includingparasitic worms (liketapeworms androundworms) and someprotozoans.[2] However, the termEntozoa is only broadly descriptive and not based on evolutionary relationships, making it a convenient but scientifically invalid grouping. Coined by Swedish-German naturalist Karl Rudolfi in 1808,[3] the term is considered obsolete and no longer used in moderntaxonomy.
Advances in taxonomy andphylogenetics have replaced such groupings with more precise classifications based on evolutionary relationships.[4] Today, these organisms are classified within differentkingdoms orphyla, such asProtozoa (single-celled organisms, likePlasmodium, a cause ofmalaria);Nematoda (roundworms, including the genusAscaris); andPlatyhelminthes (flatworms, like tapeworms andflukes).[5]
The term Entozoa was initially used at a broad taxonomic level, closer to the rank of akingdom or a similarly overarching group in older biological classifications. It functioned as a general, non-systematic category for all internal parasites, reflecting the limited understanding of evolutionary relationships in the early 19th century.