Archigetes iowensis sp. n. (Cestoda: Caryophyllaeidae) from Cyprinus carpio L. and Limnodrilus hoffmeisteri Claparède

Gravid adults of Archigetes iowensis sp. n. are described from the intestine of the cyprinid fish, Cyprinus carpio L. and from the seminal vesicle of the tubificid oligochaete, Limnodrilus hoffmeisteri Claparède from the Iowa River, Hardin County, U.S.A. A. iowensis occurs in tubificids throughout the year, but infection of carp is strictly seasonal. Cestodes becoming gravid in oligochaetes are believed to represent neotenic procercoids of those found in carp.