Abstract
The recent mollusc assemblages of the Vltava River, the longest river in the Czech Republic (430 km), and its valley were studied (South and Central Bohemia). Altogether, 162 species of terrestrial and freshwater molluscs representing 65% of the total Czech malacofauna, were recorded at 532 sites studied between 1940 and 2013.
Considering high species richness and diversity of mollusc fauna, the Vltava River valley ranks among the malacologically richest areas in the Czech Republic despite (1) the strong migration barrier of the nine dams on the upper and middle river stretches, (2) the long-term human influence in a whole river valley during the Holocene and, (3) the intensive agriculture in the lower part of the river floodplain. The river phenomenon, partly developed in the upper river stretch and fully developed in the middle part of the river, is the leading cause of such remarkable species richness.