CHARACTERIZATION OF DNA RESTRICTION PROFILES AND RIBOSOMAL-RNA GENE RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS OF PROTEOCEPHALUS-EXIGUUS AND P-NEGLECTUS FROM GEOGRAPHICALLY DISTINCT REGIONS

The total DNA of two morphologically similar cestode species of the genus Proteocephalus parasitizing coregonid and salmonid fish, P. exiguus La Rue, 1911 and P. neglectus La Rue, 1911, was compared. The methods of DNA analysis involved digestion of the total DNA with restriction endonucleases and Southern blotting hybridization with the ribosomal DNA probes pSM 889, pSM 389 and pSM 890. No inter-specific variation was found between the two proteocephalid species. Distinct differences in RFLP patterns were recorded between two geographically distinct population of P. neglectus after BspRI digestion; after EcoRI digestion and following hybridization with the P-32-labelled probe pSM 890 and after BamHI digestion and hybridization with the P-32-labelled probe pSM 889. The high degree of genetic similarity revealed in the two Proteocephalus spp. could be a further argument for the conspecifity of both taxa.