The Life Cycle of Archigetes iowensis (Cestoda: Caryophyllaeidae)

The life cycle of the caryophyllaeid cestode Archigetes iowensis was studied in naturally and experimentally infected hosts. Adults are seasonal parasites of the fish, Cyprinus carpio, while larvae occur in the seminal vesicles of the oligochaete, Limnodrilus hoffmeisteri. Procercoids are characterized by a well-formed scolex, fully developed reproductive organs, and by a cercomer. Larvae occasionally produce eggs within the annelid host. Feedings of infected annelids to fish did not provide conclusive evidence regarding the manner in which fish acquire their infections. The periodicity of adults in fish seems to result from changes in the resistance of carp to these helminths.