Dr. Murai Éva szerk.: Parasitologia Hungarica 14. (Budapest, 1982)
Parasit, hung. 14. 1981-1982 Occurrence of two species of Thelohanellus (Myxosporea: Myxozoa) of Far-Eastern origin in common carp populations of the Hungarian fish farms Dr. Kálmán MOLNÁR — Dr. Éva KOVÁCS-GAYER Veterinary Medical Research Institute, Hungarian Academy of Sciences, Budapest, Hungary — Central Veterinary Institute, Budapest, Hungary "Occurrence of two species of Thelohanellus (Myxosporea: Myxozoa) of Far-Eastern origin in common carp populations of the Hungarian fish farms" - Molnár, K. - KovácsGayer, É. - Parasit. Hung. , 1_4^ 51-55. 1981-82. ABSTRACT. In carp raised in Hungarian fish farms two Thelohanellus species were found which differed morphologically and in their localization on the host. These parasites probably reached Eastern Europe with the introduction of the amur wild c p (Cyprinus carpio haematopterus) and were introduced into Hungary through natural waters. We have proved that T. nikolskii Achmerov, 1955 developing on the carp fins and T. hovorkai Achmerov, 1960 living on the serous membranes of the inner organs are highly host-and organospecific parasite species, and, in contrast to earlier suggestions, they are not identical with T. dogieli. During a routine veterinary examination of common carp raised in Hungarian fish farms two Thelo hanellus species of significantly different morphology were found on the fins and on the serous membranes of the swimbladders, respectively. The parasites were identified as Thelohanellus nikolskii Achmerov, 1955 and T. hovorkai Achmerov, 1960 which had been first detected in waters of the Far East. The occurrence of a Thelohanellus species in Hungary was first recorded by JENEY (1979) who identified the parasites found on the fins of the common carp (Cyprinus carpio) as T. dogieli Achmerov, 1955 and believed that this parasite was introduced to Europe by the Far-Eastern carps. Prior to this, in Europe Thelohanellus species had not been described from the common carp and only T. pyriformis (Thélohan, 1892), T. fuhrmanni (Auerbach, 1909), T. oculileucisci (Trojan, 1909), T. notatus (Mavor, 1916) and T. swellengrebeli (Schuurmans-Stekhoven, 1918) were known from other carp species (BAUER, 1948; PETRUSHEWSKY and BAUER, 1948; LOM, 1961; SCHÄPERCLAUS, 1954). In Far-Eastern waters six Thelohanellus species were described from the common carp: five by ACHMEROV (1955, 1960) from the amur wild carp (Cyprinus carpio haematopterus) and one by HOSHINA and HOSODA (1957) in Japan. Among these species SHULMAN (1962, 1966) regarded only T. dogieli to be valid, and considered T. nikolskii, T. amurensis Achmerov, 1955, T. cyprini Hoshina and Hosoda, 1957 and T . hovorkai to be synonymous with T. dogieli, and T. acuminatus. Achmerov, 1955 to by synonymous with T. fuhrmanni . The aim of the present paper is to prove - on the basis of spore morphology and the characteristic localization of the cysts - the validity of T. nikolskii and T. hovorkai s pp. recently found in Hungarian fish farms.
