Glochidia Infection of Endemic Fishes from Lake Prespa, N. Macedonia

Large freshwater mussels (Unionida) are long-lived, have large bodies, and produce thousands to millions of larvae (glochidia) that usually must attach host fish tissue complete their life cycle. This is an obligate parasitic stage mussel larvae. However, less than one in onemillion find a suitable survive. The degree specificity varies among unionid species, from specialists can successfully parasitize only or few closely related species generalists development on taxonomically broad range species. In addition, the most threatened groups animals. due habitat destruction, introduction non-native loss which parasites. Glochidiosis harms by affecting growth; other hand, play important role freshwaters improving water quality ridding bacteria, algae, pollutants, they indicator quality. During our parasitological survey Macedonian part Lake Prespa April 2022, many glochidia were found gills, skin, fins two endemic fishes, roach (Rutilus prespensis) nase (Chondrostoma prespense), tens host. We thus recorded these as new hosts A. cygnea.