Life Cycle of Spinitectus micracanthus Christian, 1972 (Nematoda: Rhabdochonidae) from the Bluegill, Lepomis macrochirus Rafinesque, in Missouri with a Note on Spinitectus gracilis Ward and Magath, 1917

The development of Spinitectus micracanthus is described in the intermediate host, Hexagenia sp. (Insecta: Ephemeroptera), and in the definitive host, Lepomis macrochirus. Larval development occurs primarily in the abdominal muscles of Hexagenia sp., and encysted, third-stage larvae were present in the muscles 20 days postinfection. Males with sperm in the reproductive tract were recovered from the intestine of the definitive host 26 days postinfection, and females containing eggs were recovered from the intestine 36 days postinfection of the definitive host. Infective larvae of S. micracanthus were compared with larvae of S. gracilis obtained from naturally infected Hexagenia sp.