DESCRIPTION OF MYXOBOLUS-BULBOCORDIS SP-NOV (MYXOSPOREA, MYXOBOLIDAE)FROM THE HEART OF BARBUS-SHARPEYI (GUNTHER) AND HISTOPATHOLOGICAL CHANGES PRODUCED BY THE PARASITE

A new myxosporean, Myxobolus bulbocordis sp. nov., has been found in t he heart of a Mesopotamian fish, Barbus sharpeyi (Gunther), in rivers in Southwest Iran. Cysts containing matured spores were located on the serosa of the atrium cordis, bulbus arteriosus, larger gill arteries and inside the wall of the bulbus. The species showed an affinity to c onnective tissue cells and was never associated with the muscles. Matu re cysts were surrounded by a connective tissue capsule composed of tw o to three layers. Spores in disrupted cysts were infiltrated by epith elioid cells and macrophages. The spores found in Barbus sharpeyi diff ered in size and morphology from species known from other barbels.