Occurrence of Gyrodactylus spp (Monogenea: Gyrodactylidae) From Iranian Freshwater Fishes

Abstracts: thirty three gyrodactylus spp. have been found on the gills and bodysurface of both wild and farmed freshwater fishes in iran. among them, nine specieshave been identified up to the species level, which are new locality records. theidentification of the others, mainly belong to endemic wild freshwater fishes, needfurther studies. among the known species, gyrodactylus derjavini (mikhailov, 1975)has been found on the gills, caudal and anal fins of the caspian salmon (5al/1/0 truttacaspius) and rainbow trout (oncorhyn chus mykiss) . these species are very harmful tosalmonid fingerling production industry of iran. in warm water cultured fishes, g.sprost ona, with widest host range, infects common carp tcyprinus carpio), silvercarp thyp ophtholmichthys molitrixi and big head carp (aristichthys nobilis) in almostall fish farms of iran. other species, which will be discussed here from their economicimportance and host specificity points of view, are g. cyprini, g, elegans, g, foss ilis,g. kobaya shii, g. pr ostae, g. shulmani and g. stankov ici. furthermore thepathogenecity of gyrodactylus spp are discussed and new technology (dnasequence) for precise identification of parasites is also recommended