The present studies with application of classical strain crosses and RAPD-PCR analyses showed the existence of different genetic species (syngens) within Paramecium jenningsi. So far the existence of only one syngen has been accepted. It was found that strains from Saudi Arabia, India, and China compose one genetic species (syngen 1) and six strains from Japan compose second genetic species (syngen 2).
E. Przybos, Department of Experimental Zoology, Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Slawkowska 17, 31-016 Krakow, Poland