Parasitic Barnacles

Rhizocephala are derived barnacles that parasitise decapod crustaceans. Their body plan is uniquely reduced in an extreme adaptation to their parasitic lifestyle, and makes their relationship to other barnacles unrecognisable in the adult form. The name Rhizocephala derives from the Greek roots ῥίζα (rhiza, "root") and κεφαλή (cephale, "head"), describing the adult female, which mostly consists of a network of thread-like extensions penetrating the body of the host.