Dr. Murai Éva szerk.: Parasitologia Hungarica 20. (Budapest, 1987)

First record of a common carp parasite, Dactylogyrus molnári Ergens et Dulma, 1969 (Monogenea) in Hungary Dr. Kálmán MOLNÁR Veterinary Medical Research Institute, Hungarian Academy of Sciences, Budapest, Hungary "First record of a common carp parasite, Dactylogyrus molnári Ergens et Dulma, 1969 (Monogenea) in Hungary" - Molnár, K. - Parasit, hung., 20: 4 1-43. 1987. ABSTRACT. Another member of the rich Dactylogyrus fauna of the Amur wild carp (Cypjnm^_cji£pj^Jiaejm in the Far East, Dactylogyrus molnári Ergens et Dulma, 1969, has been introduced to Europe, presumably by fish importations. At present in Hungary the common carp (Cyprinus carpio) is parasitized by D. achmerowi

, D. molnári and D. sahuensis, in addition to D. anchoratus, D. extensus

, D. minutus and D. vastator demonstrated earlier. KEY WORDS. Monogenea, Dactylogyrus, Cyprinus carpio, new area of spread. Up to the beginning of intensive fish transfers in the early 19 60s, four commonly occurring Dactylogyrus species had parasitized the common carp (Cyprinus carpio) in Europe: D. anchoratus (Dujardin, 1845), D. extensus Mueller et Van Cleave, 1932, D. minutus Kulwiec, 1927, and D. vastator Nybelin, 1924. The Dactylogyrus fauna of the Amur wild carp (Cyprinus_cajpi^JmemaU)pteru_sJ is considerably richer. In addition to the four Dactylogyrus species also occurring in Europe, this common carp subspecies is parasitized by D.achmerowi Gussev, 1955, D. falciformis Achmerow, 1952, D. lopuchinae Jukhimenko. 1981, D. molnári Ergens et Dulma, 1969, D. mrazeki Ergens et Dulma, 1969, D. sahuensis Ling, 1965, and D. yingwenyingae Gussev, 1962 in the watershed of the River Amur and in Mongolia, and by D. biwaensis Ogawa et Egusa, 1982 and D. takahashii Ogawa et Egusa, 1982 in Japan (GUSSEV, 19851. Due to the fish transfers and the frequent importation of koi carp, a species kept as ornamental fish in the Far East, it seems increasingly probable that the eastern Dactylogyrus species will be added to the parasite fauna of the European common carp. The first step of this process was the appearance of D. achmerowi in the European part of the Soviet Union (GUSSEV, 1962). As it has been reported by MOLNÁR (1984), in addition to D. achmerow

i , D. sahuensis has also appeared in Hungary. In the present work the incidence of another Far-Eastern parasite new to Hungary, D. molnari

, is reported. MATERIALS AND METHODS The study material was obtained from two large fish farms situated in Eastern Hungary. The gills of two-to-three summer-old common carp from these farms was regularly checked for the presence of parasites. After the first observation of a Dactylogyrus species previously not recorded in Hungary, 10 fish specimens each were dissected between May and October 1987. Immediately after the fish had been killed, the Dactylogyrus specimens were removed