Larval trematodes [Digenea] in molluscs from small water bodies near Ceske Budejovice, Czech Republic

A total of 2802 molluscs from two fishponds and one swamp in the vicinity of České Budějovice, South Bohemia, were examined between 1998 and 2000. A total of 12 species of molluscs were infected (33.9%, n = 951) with larval trematodes of 28 species (26 species were represented by cercariae, 8 species by metacercariae; 6 species were found both as cercariae and metacercariae). The dominant species found as cercariae were Tylodelphys excavata (Diplostomidae), Plagiorchis elegans (Plagiorchiidae), Echinostoma spiniferum sensu Našincová (1992) and E. revolutum (Echinostomatidae). Three cases of double infections with cercariae were found; metacercariae often occurred together in one snail (up to five species). The most infected hosts were Planorbarius corneus (78.2%, n = 662), Lymnaea corvus (65.5%, n = 55) and Lymnaea stagnalis (47.1%, n = 473). Most of the trematode species reported mature in birds and are widely distributed in other parts of Europe. The common species found as cercariae are illustrated.