Abstract / Introduction / Summary:
A monthly investigation into the occurrence of the lernaeid copepod Lernaea cyprinacea Linnaeus, 1758 on fishes was conducted in the Matsuita River, a tributary of the Kurose River, Hiroshima Prefecture, Japan, for one year from November 2007 to October 2008. Of the 10 fish species collected (four cyprinids, one bagrid, one amblycipitid, two centrarchids, one odontobutid, and one gobiid), only three species, i.e., bluegill Lepomis macrochirus Rafinesque, 1819 (Centrarchidae), dark chub Nipponocypris temminckii (Temminck and Schlegel, 1846), and pike gudgeon Pseudogobio sp. (both Cyprinidae), were found to be infected with L. cyprinacea. Among these species, bluegill was most frequently infected, which suggests that the species serves as an important host in the river. Ovigerous females of L. cyprinacea were collected during summer months (June to August).