Dr. Kassai Tibor - Dr. Murai Éva szerk.: Parasitologia Hungarica 8. (Budapest, 1975)

(MATTHEIS and SP AN GENBERG, 1974), however, this parasite has likely been introduced by imported fishes. The demonstration of a single Khawia. identified as K. sinensis in a carp in Czechoslovakia in 1963 (PRIBYSLAVSKY et al., 1965) was a confusing event; the authors finally considered that species as indigenous in the Danube basin, because they excluded the possibility of the introduction. Since, however, no further occurrence of the species had been reported in Czechoslovakia during the last 10 years and the parasite was found to differ from K. sinensis in certain morphological details, the specimen, described by PRIBYSLAVSKY et al. may weU have represented another species. No conclusions have been drawn in respect of the frequency of occurrence of C. fimbriceps, because the period in which the present study was conducted did not coincide with the peak occurrence of the species, which is during spring and summer. The morphological characters observed in this study correspond with those described by KULAKOVSKAYA and KROTAS (1961) for both K. sinensis and C. fimbriceps

, but certain important details of the former do not accord with HSU's (1935) original description. Our exemplars showed different proportions in the dimensions of testes and viteUaria than those given by HSÜ, the testes of our specimens being larger. Against this, CALETINE and ULMER (1961) mention the larger size of viteUaria in relation to testes as an important differentiating feature from other species. According to HSÜ, the uterovaginal duct bears spines aU over its inner surface, but we failed to find these structures in the exemplars studied. We found that the uterovaginal duct forms a funnel-like distension, 240-300 « in diameter, beneath the cirrus pouch, but HSÜ made no mention of this important morphological detail. Convolutions of the vas deferens anterior to the cirrus pouch were found by HSÜ over an 50 u long area, whereas in our specimens the pyramid-shaped area occupied by convolutions of the vas deferens was least 1 mm long. The Khawia species recently found in Hungary is clearly identical with the one fairly common and indigenous in the Soviet Union, originated from the Far East. However, the important morphological deviations between our specimens and the parasite originally described by HSÜ (1935) as K. sinensis may rise the suspicion of non-identily of these two parasites. Nevertheless, we belive that the species found by us is identical with HSU's parasite and the aforementioned differences are due to errors in the original description, because even in HSÜ's original drawings the testes are obviously larger than the vitellaria. Summary The incidence of the carp parasite K. sinensis was found to be 35 % in the pond farms associated with the catchment area of the river Tisza, whereas only sporadic incidence was noted in carp ponds localizing in the Danube watershed area. The conclusion lies close at hand that the parasite spread to Hungary from the Soviet Union, where it was indigenous, through the river Tisza. The morphology

1 of K. sinensis and another economically important caryophyllaeida, C. fimbriceps, was studied by histological methods. C. fimbriceps corresponded in every respect with the related literary data, but certain important details of K. sinensis differed from those given in the original description. These deviations were ascribed to inadequacies of the original description. It is pointed out that - contrary to what is said in the original description - testes of K. sinensis are in fact larger that the vitellaria. sa