Dr. Murai Éva szerk.: Parasitologia Hungarica 16. (Budapest, 1983)

cies, although earlier MAEDER (1973) and SALAMI-CADOUX and GREGORIO (1976) were of the opinion that D. fischthalicus was a synonym with D. subclavatus

. Enlisting the differences detectable between the two species in question we should emphasize those found in their reproductive biology. Members of the European population are ovoviviparous while those of the African "

D. subclavatus" (south of the Sahara), examined in this respect (BOURGAT and KULO, 1977; SALAMI-CADOUX and GREGORIO, 1976; PIKE, 1979) are ovoparous. Beside these, the intermediate hosts of Central African "

D. subclavatus" were found to be Bulinus forskalii and Segmentorbis kinisaensis (BOURGAT and KULO, 1977) while D. subclavatus, in Europe, develop in different planorbid snails. At the same time, our experimental infection of Bulinus truncatus with miracidia of this fluke were unsuccessful. The differences found between the European and the Central African D. subclavatus in the development of the eggs laid, argentofile structure of the cercariae, intermediate host specificity suggest that D. fischthalicus is a distinct species and BOURGAT and KULO (1977), SALAMI-CADOUX and GREGORIO (197 6) as well as PIKE (1979) had worked with this species and not D. subclavatus. Fig. 22: Catadiscus dolichocotyle (Cohn, 1903) Fig. 23: Dermatemytrema trifoliata Price, 1937 (After Marié-Garzon and Gortari, 1965) (after Price, 1937)