Diplostomum and Ornithodiplostomum scardinii (Diplostomidae, Digenea) species from naturally infected birds (Anatinae) in the Czech Republic and in Poland: morphological, morphometric and ecological features

The study aimed to describe morphological and morphometric characteristics of species representing the genera Diplostomum Nordmann, 1832 and Ornithodiplostomum Dubois, 1936, originating from naturally infected birds in the Czech Republic and in Poland, and to compare their species richness and the intensity of infection in their avian hosts. Diplostomum mergi Dubois, 1932, D. parviventosum Dubois, 1932, D. phoxini (Faust, 1918), D. pusillum (Dubois, 1928), and Ornithodiplostomum scardinii (Schulman, 1952) were found in the gossander (Mergus merganser). D. parviventosum was found in the velvet scoter (Melanitta fusca). D. pungitii Shigin, 1965 was found in the tufted duck (Aythya fuligula), common eider (Somateria mollissima), common goldeneye (Bucephala clangula), and in the long-tailed duck (Clangula hyemalis). D. spathaceum (Rudolphi, 1819) was found in the mallard (Anas platyrhynchos). Morphology and morphometry of those Diplostomum species from the Czech Republic and from Poland were not analyzed before. The morphological and morphometric description of the adult form of O. scardinii presented in this study has been the first such description of a specimen obtained from a naturally infected bird. The highest intensity of infection was observed in the gossander (D. pusillum and D. mergi). Study results provided new data on the occurrence of the Diplostomum and O. scardinii trematodes in the Czech Republic and in Poland.