J. Pazooki - Department of Biological Sciences, Shahid Beheshti University, P. O. Box: ۱۹۸۳۴, Tehran, Islamic Republic of Iran.
M. Masoumian - Iranian Fisheries Research Organization, Department of Fish Diseases, P. O. Box: ۱۴۱۵۵-۶۱۱۶, Tehran Islamic Republic of Iran.
M. Yahyazadeh - Research Center of Natural Resources and Animal Sciences, P. O. Box: ۶۶۹, Urmia, Islamic Republic of Iran.
J. Abbasi - Islamic Azad University of Urumia, Faculty of Veterinary Medicine, P. O. Box: ۹۶۹, Urmia, Islamic Republic of Iran.

A systematic parasitological examination was carried out on ۲۶۶ freshwater fish speci-mens, belonging to ۱۱ species, from Northwest of Iran during the period from Summer ۲۰۰۱ to Summer ۲۰۰۲. Twelve parasite species including Diplostomum spathaceum, Al-locreadium isoporum, Ligula intestinalis, Digrama sp., Caryophylleus laticeps, Rhabdocona hellichi, Eustrongylides excisus, Argulus foliaceus, Lamprolegna compacta, Myxobolus musayevi, M. cristatus, and Neoechinorhynchus rutili were isolated and identified. It was concluded that Sander lucioperca, Albornoides bipunctatus, Capoeta capoeta, Carassius carassius and Barbus capito were five new hosts for those parasites in Iranian freshwater fishes. Furthermore, Myxobolus cristatus is recorded for the first time among Iranian freshwater fishes. All the parasites were collected from natural waters, but these rivers form a very important water reservoir in this area and these parasites can injure cultured fishes under certain conditions.

IRAN, Freshwater fishes, Metazoan, Parasites