| Popis: |
Two Ponto-Caspian gobiid species, the racer goby, Babka gymnotrachelus, and the monkey goby, Neogobius fluviatilis, the introduced fishes in the Vistula River, Poland, were found being infected with metacercariae of Bucephalus polymorphus. The encysted larvae were located in muscles and fins of these fish. The adult specimens occurred in the gut of another non-indigenous species, the Chinese sleeper Perccottus glenii. The life cycle of B. polymorphus in the Vistula River drainage includes three non-indigenous components: 1) the zebra mussel Dreissena polymorpha, the source of cercariae; 2) gobiids (the racer and monkey gobies), which are new in this water drainage but could play more important role in the life cycle than habitual cyprinids, thanks to their small size (favorable in transmission through the food-web); 3) the Chinese sleeper, a new accidental definitive host. The presence of these non-indigenous components in the life cycle maintains the distribution and further spread of B. polymorphus in the colonized area. |
