Dr. Murai Éva - Gubányi András szerk.: Parasitologia Hungarica 28. (Budapest, 1995)

MATERIALS AND METHODS Philometra specimens were collected during parasitological surveys on fishes of the River Karun (River Tigris region, Persian Gulf system) in two different years. In December 1992, 4 B. luteus (Heckel, 1843), 3 B. sharpeyi (Günther, 1874) and 4 B. grypus (Heckel, 1843) specimens of 2-4 years of age were dissected for parasites. From May to October of 1994, 32 specimens of B. luteus, 40 B. sharpeyi, 20 B. grypus and 4 B. rajanorum (Heckel, 1843) specimens aged 2-3 years were examined for the occurrence of nematode parasites. A general parasitological dissection was performed. In order to detect Philometra species, meticulous care was taken in checking the abdominal cavity and the swimbladder. Organs of the abdominal cavity were examined in 0.65% saline and the cavity was rinsed with this solution which was collected in a Petri dish. Males and retarded females were looked for in the serous membrane of the second sac of the swimbladder, which was peeled off the sac wall. Nematodes found were placed into 4% formalin and preserved until their detailed study. The isolated Philometra specimens were cleared in lactophenol to examine their surface and inner structure. The structure of the cephalic papillae and the buccal region was studied in en face view after decapitating the gravid females with a sharp blade (Moravec 1994). Measurements were taken under an Olympus microscope. RESULTS During the survey conducted in 1992 two specimens of B. luteus proved to be infected by 4 and 3 specimens, respectively, of gravid females of a Philometra sp. in the abdominal cavity. In 1994, infection by Philometra sp. was found only in B. sharpeyi. Six specimens of that fish harboured males and matured but retarded females under the serosa of the second sac of the swimbladder. Although the specimens found in these two closely related fishes presumably represent the same species, until further studies specimens found in B. luteus and B. sharpeyi are described separately. Philometra sp. from Barbus luteus (Heckel, 1843) Site of infection: Abdominal cavity Locality: River Karun Specimens found: 7 gravid females Description of gravid females (Figs la, b): Body of live female red in colour, cylindrical, tapering slightly to both ends. Both ends of body rounded. Cuticle thick, with smooth surface. Length of the body 80 to 110 mm, maximum width 1.9 mm. Oral opening comparatively small, spherical. Head end without distinct projections. Cephalic papillae indistinct, arranged in double circle. In the inner circle eight small papillae are located. The outer circle composed of four doubled papillae and two amphids. Posterior end of the body rounded with two small lateral papilla-like projections. Length of oesophagus 1.59 (1.30-1.67) mm. The muscular oesophagus narrow, swollen near mouth to form a distinct bulb. There is an oesophageal gland provided with a giant cell nucleus located at about its