Abstract / Introduction / Summary:
Adult females of the lernaeopodid copepod Salmincola edwardsii (Olsson, 1869) were found infecting southern Asian Dolly Varden, Salvelinus malma krascheninnikova Taranetz, 1933 (Salmoniformes: Salmonidae), from the Rausu River, Hokkaido Island, Japan. The bullas of copepods were embedded by the distal ends of shortened gill filaments, which formed bulbous swellings. The gill filaments adjacent to copepods were club-shaped and adhered at their distal portions, and often abbreviated in length. However, no such serious injury was found at attachment sites in the branchial chamber. Thus, the copepods infecting the gills are considered to have stronger negative impacts on the host fish than those parasitizing the branchial chamber.