fish parasites in zarivar lake

twenty four ecto- and endo- parasite species were found in different organs of eight na-tive and exotic fish species in zarivar lake situated in the far west of iran. overall, 1000 fish specimens belonging to the dactylogyridae, gyrodactylidae families the cyprinidae, poeciliidae and mastacembelidae families were examined during 2001 and 2002. of them, five protozoans, including trichodina pediculus, trichodina sp and myxobolus molnari, a pansporogenic stage of the myxosporean plasmodia and ichthyophthirius multifiliis were recorded. of the metazoan parasites, 12 monogenean species, mostly belonging to the dactylogyridae, gyrodactylidae families and the ancyrocephalinae subfamily, were found and identified at species and genus level. the number of helminthes reached 15 by adding one digenea metacercaria (diplostomum spathaceum) and 2 coelozoic cestoda species. crustacean species found on both of native and exotic fishes, belonging to copepoda and branchiora orders comprised of argulus foliaceus and lernaea cyprinacea, in addition an unknown argulus was also found on skin and gills of spiny eel which identified to genus level. the only nematode found in the intestine of common carp was identified as pseudo-capillaria tomentosa. besides the first record of parasites of spiny eel, the seasonal preva-lence of ligulosis is presented. additionally, zoogeographical analysis and species compo-sition of parasitic fauna of zarivar lake are discussed.