Distribution of the Ponto-Caspian polychaeta Hypania invalida (Grube, 1860) in inland waters of Serbia

The aim of this paper is to present the distribution of the non-native species Hypania invalida (Polychaeta) within Serbian waters. In 1971, this species was found for the first time in the Danube and the Sava Rivers. According to our results, H. invalida is now widespread within potamon-type rivers that are under the influence of hydromorphological alterations and exposed to intensive ship traffic. The distribution of this polychaete species, as well as some other alien aquatic invertebrate taxa Branchiura sowerbyi, Chinese pond mussel Anodonta woodiana, Spiny cheek crayfish Orconectes limosus and Asian clam Corbicula fluminea, further indicates that heavily modified waterways are suitable recipient areas for species introduction and adaptation.