Dr. Kassai Tibor - Dr. Murai Éva szerk.: Parasitologia Hungarica 6. (Budapest, 1973)
while YAMAGUTI (1934) reported of half-embryonated eggs. YAMAGUTI (1959) accepted YEH' s views, and in his book B. opsari- ichthydis was considered as a synonym of B. acheilognathi . LIAO and SHIH (1956) established, when studying the biology of B . gowkongensis , that the maturity of eggs changes by seasons,consequently the worms may deliver both fully embryonated and half-embryonated eggs. B. gowkongensis arrived in Europe by the introduction of planteating fishes. It was detected first by MALEVITZKAYA (l958)from the European part of the Soviet Union, by RADULESCU and GEORGESCU (1962) from Rumania, and by BUZA et al. (1970) from Hungary. OTTE et al. (1972) found the parasite also in Austria, however, it was identified as B. acheilognathi * and not as B_. gowkongensis . According to DUBININA (1971) B. gowkongensis is presumably identical with B. opsariichthydis . Prom Hungary besides B.gowkongensis the occurrence of two other Bothriocephalus species have been announced. MURAI (1971) dealt in details with the parasite called B. claviceps of Anguilla anguilla, regarded as a partly maritime fish. MOLNÁR (1968a) described a new species from Phoxinus phoxinus under the name B. phoxini , and distinguished it from the previous ones by morphological and epidemiological features. The seasonal incidence of this species was also discussed by MOLNÁR (1968b). The present work has three aims. Firstly an attempt is made to prove the validity of B . phoxini against B. gowkongensis which was recently recorded from Hungary. Secondly, a detailed morphological description of the anatomy of these two parasites are given. Thirdly, as in the course of description of B . phoxini in 1968 the type-specimens have not been indicated, the holotype and paratype specimens are now designated. + It is unequivocal from the description of the authors that the species discussed was introduced to Austria by Ctenopharyngodon idella specimens originating from Hungary, consequently the parasite is identical with the species known as B . gowkon gensis in East-Europe .
