Plötner, J. (in press): Genetic diversity in mitochondrial 12S rDNA of western palearctic water frogs (Anura, Ranidae) and implications for systematics. J. Zoo. Syst. Evol. Research

Abstract -- The nucleotide sequence of a part of the mitochondrial 12S rRNA gene of eight western palearctic water frog species was analyzed. The results support the species status of Rana bedriagae, R. bergeri, R. epeirotica, R. lessonae, R. perezi, R. ridibunda, R. saharica, and R. shqiperica. Furthermore, the differences between the mt 12S rDNA segments of lake frogs from Greece and Yugoslavia on the one hand and the 12S rDNA segments of lake frogs from Georgia, Uzbekistan, and Turkmenistan on the other hand provide new evidence for the existence of two cryptic species. It seems very probable that lake frogs from Georgia, Uzbekistan, and Turkmenistan belong to R. ridibunda whereas lake frogs from Greece and Yugoslavia represent R. kurtmuelleri, a form which had already been described by Gayda (1940). Additional investigations are needed to clarify this problem. The very high similarity between the analyzed 12S rDNA segments of German R. ridibunda and R. lessonae support the hypothesis that mtDNA of R. lessonae was transmitted into the mitochondrial gene pool of R. ridibunda probably as a result of backcrosses with the hybridogenetic hybrid R. kl. esculenta. The obtained genetic data confirm the very close phylogenetic relations between R. perezi and R. saharica. However, it is not yet clear whether both species represent an adelphotaxon. Furthermore, R. shqiperica, R. lessonae, and R. bergeri on the one hand and R. ridibunda and R. bedriagae on the other hand are considered to be seperate lineages which seem to be sister taxa. According to the mt 12S rDNA data R. epeirotica seems to be closer related to the supraspecific taxon R. ridibunda/R. bedriagae than to R. lessonae/R. bergeri/R. shqiperica. Thus, it can be excluded that R. shqiperica and R. epeirotica represent sister species.

Key words:Ranidae, Rana, western palearctic water frogs, systematics, mitochondrial 12S rDNA, sequence analysis