Fish Monogenea of Poland. X. Parasites of Alburnoides bipunctatus (Bloch).
Twenty three Alburnoides bipunctatus from 3 locations in Poland, the rivers Tanew (15 fish), Skawa (1 fish) and a mountain stream in Wołkowyjka (7 fish) were examined. The following monogeneans, including Gyrodactylus euzeti sp. nov., are described, and their anchors and marginal hooks figured : G. gracilihamatus, G. hronosus, G. alburnoidesi, Gyrodactylus sp., Octomacrum europaeum, and Paradiplozoon alburni. All are recorded from Poland for the first time. The description of the new species is based on 4 specimens from the gills of A. punctatus caught from the River Tanew in Rebizanty (3 parasites) and from the stream in Wołkowyjka (1 parasite). It is most closely related to G. laevis from Phoxinus phoxinus but differs from this species in the size and shape of its marginal hooks: in G. euzeti they are longer and the sickle and handle are thicker, and end with a prominent swelling. The anchors of the new species are also thicker, and the ventral bar a little longer, than those of G. laevis.