Dr. Kassai Tibor szerk.: Parasitologia Hungarica 2. (Budapest, 1969)
Significant pathological lesions were found in three species. At the site of its attachment, Tracheliastes maculatus causes haemorrhages under the scales so that especially during the spring and summer period, large reddish spots (2-8 scales) on the body surface of breams in Lake Balaton. Even more conspicuous lesions can be observed at the site of attachment of Ler- naea cyprinacea and Tracheliastes polycolpu3 ; at the base of the fins mainly in smaller-bodied fish there develop vivid red and gelatinous swellings, the size of a pin-head or lentil, where the organ of attachment has penetrated the epidermis. The occurrence in Hungary of Neoergasilus japonicus merits special attention since, until the publication of HANEK's paper (1968), this species was known only in the Ear East, being characteristic of the carp species in that region (IYASIK, 1968). This parasite was found in 1965 in the River Tisza, and since then has been collected many times from the Rivers Tisza and Danube, and the fish ponds at Dinnyés. Occasionally it has cauâed severe infection. The chief characteristics of the parasite agree with the description published by TIN (1956). A detailed anatomical examination will be made after collecting a larger number of specimens. With regard to the occurrence of Neoergasilus .japonicus in the Carpathian Basin (information relating to the River Latorca, recorded by HANEK in 1968, is relevant here), one may question whether this rather frequent parasite is autochthonous to Europe or has been introduced. That the species is indigenous is supported by the fact that it is very agile in contrast to all known Ergasilids , and .that even the gravid females are able to swim rapidly and change hosts (this latter point was confirmed experimentally), leaving and once more attaching itself to fish placed in water for dissection. Therefore the imagos of Neoergasilus japonicus cannot be considered stationary parasites. Their temporary parasitism is further indicated by the development of their swimming legs and the poorly developed state of the attaching apparatus.
