Range Extension of the Ponto-Caspian polycheate Manayunkia caspica Annenkova, 1929 (Annelida: Fabriciidae) in the Danube River

Abstract

Freshwater polychaetes are the most diverse in the Palaearctic, including the Ponto-Caspian region as an important area of diversity. One of several polychaete species that are spreading from this area is Manayunkia caspica. For a certain period of time, the range of this species in the Danube River has been limited, probably because of the Iron Gate dam. This Ponto-Caspian species, which is established along the Romanian stretch of the Danube River, was recorded for the first time in the Serbian part of the river in November 2005, and subsequently, it has been repeatedly found in the Iron Gate II Reservoir at 934 rkm (the town of Kladovo). During the Joint Danube Survey 3 (JDS 3) in September 2013, it was observed that M. caspica has extended its distribution from the Ponto-Caspian region to Central and Western Europe, with Klizska Nema (Slovakia/Hungary) as the most upstream locality. The findings presented herein show that the distribution of M. caspica has for the first time expanded upstream of the Iron Gate, where it appeared to have established population, making this species a regular component of the macroinvertebrate fauna along the entire stretch of the Danube River.