Invasion of Corbicula fluminea (Müller, 1774) (Bivalvia: Corbiculidae) in water bodies from the East Aegean River Basin in Bulgaria

Since the first record of the invasive Corbicula fluminea (Müller, 1774) in Bulgaria in 2001 (Danube River at Vetren village), the Asian clam spread in a relatively short time to most of the Bulgarian Danube tributaries. For almost a decade after, the mussel was registered in many surface freshwaters in Bulgarian Danube River Basin, including rivers, lakes and reservoirs.

The aim of the current study is to report the finding of C. fluminea in lotic environment of the East Aegean water basin in Bulgaria. As a result of large-scale research of macroinvertebrate communities in different types of water bodies, 6 new localities of this species were registered – two in Tundzha River and four – in Maritsa River, all situated in their lower stretches. Considering the current known distribution of the species, we discussed the possible path for invasion of the largest rivers in south-eastern part of Balkan Peninsula and the probability of rapid spread of Corbicula in their tributary systems.