SOME REMARKS ON THE BROAD-SPECIFICITY OF FIMBRIARIA-FASCIOLARIS (CESTODA, HYMENOLEPIDIDAE) IN RELATION TO FINAL AND INTERMEDIATE HOSTS

Research resulting in the description of six new species representing the genus Fimbriaria has thus revealed that the former Fimbriaria fasc iolaris (Pallas, 1781) was in fact a group of species. In the light of this, the long list of final and intermediate hosts for this species may in fact result from earlier errors in identification. Proper diagn osis of Fimbrial in to the level of the species should be based on pen etrating morphological studies of adult forms which would take account of: the structure of the oncospheral envelope, the number of genital primordia per segment of the strobila, the number of spines at the cir rus base and the length of the cirrus pouch. Proper diagnosis of speci es at the larval stage is practically impossible in natural infections because of the great similarity between the larvae of different speci es. The present state of knowledge of the genus Fimbriaria calls for a revision review of the broad specificity of the whole group in relati on to both final and intermediate hosts.