Salsuginus seculus (Monogenea: Ancyrocephalidae) Newly Recorded from Japan, Infecting the Introduced Mosquitofish Gambusia affinis

Abstract

The ancyrocephalid monogenean Salsuginus seculus (Mizelle and Arcadi, 1945) was found infecting the gills of mos- quitofish, Gambusia affinis (Baird and Girard, 1853), from Okinawa, Aichi, Tokushima, and Kyōto prefectures in Japan. These are the first records of S. seculus from Japan. This parasite was most likely introduced along with mosquitofish from Texas (USA) through Hawaii and Taiwan into Japan in the late 1910s. It appears to have low salinity tolerance.