temnocephalid

flatworm

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Last updated

July 14, 2026

Quick Summary

Temnocephalids are a type of flatworm that are parasitic on freshwater crustaceans. Unlike most other flatworms, which are found worldwide, temnocephalids primarily inhabit Central and South America, Madagascar, New Zealand, Australia, and islands in the South Pacific.1

Flatworms, in general, are adapted to a wide range of environments, including marine, freshwater, and moist terrestrial habitats. Some species can tolerate extreme temperatures and varying salt concentrations. While many flatworms are free-living, some, like the temnocephalids, have evolved parasitic lifestyles, attaching to hosts using specialized adhesive organs.2

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flatworm
Distribution and abundance
Except for the temnocephalids, flatworms are cosmopolitan in distribution. They occur in both fresh water and salt water and occasionally in moist terrestrial habitats, especially in tropical and subtropical regions. The temnocephalids, which are parasitic on freshwater crustaceans, occur primarily in Central and South America, Madagascar, New Zealand,…
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Except for the temnocephalids, flatworms are cosmopolitan in distribution. They occur in both fresh water and salt water and occasionally in moist terrestrial habitats, especially in tropical and subtropical regions. The temnocephalids, which are parasitic on freshwater crustaceans, occur primarily in Central and South America, Madagascar, New Zealand,…
Read More