Sacculina

crustacean

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Last updated

July 13, 2026

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Sacculina refers to a genus of parasitic barnacles within the order Rhizocephala. These organisms are crustaceans that have undergone significant modification for a sedentary existence.12

Sacculina are internal parasites that specifically target decapod crustaceans, such as crabs. As adults, they are highly specialized, lacking appendages, shells, and digestive systems. The female parasite invades its host and extends root-like structures throughout the host's body. This parasitic intrusion has a notable effect: it inhibits the host's reproductive development, a phenomenon known as parasitic castration.2

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barnacle
…(about 230 species), such as Sacculina, lack appendages, shell, and gut and resemble fungi. Females parasitize decapod crustaceans (crabs and allies) by sending rootlike absorptive processes through the host’s body; this intrusion inhibits the host’s reproductive development (parasitic castration). Parasites of the order Ascothoracica, the most primitive of cirripedes, are…
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…(about 230 species), such as Sacculina, lack appendages, shell, and gut and resemble fungi. Females parasitize decapod crustaceans (crabs and allies) by sending rootlike absorptive processes through the host’s body; this intrusion inhibits the host’s reproductive development (parasitic castration). Parasites of the order Ascothoracica, the most primitive of cirripedes, are…
Read More

reproductive behaviour
Crustaceans
One, Sacculina, is an example of the way in which the reproductive necessities of one species can profoundly affect the reproductive behaviour of another—in this case, the host. Several cells from a larval barnacle penetrate a crab’s body and migrate through the bloodstream until they reach…
Read More
One, Sacculina, is an example of the way in which the reproductive necessities of one species can profoundly affect the reproductive behaviour of another—in this case, the host. Several cells from a larval barnacle penetrate a crab’s body and migrate through the bloodstream until they reach…
Read More