New hypotheses on the systematics of the western Palearctic water frog complex (Anura, Ranidae)

Abstract

During the past 30 years the number of recognized western Palearctic water frog species has increased from just two at the end of the 1960s to at least 14 today. According to new sequence data from mitochondrial genes (12S rRNA. ND3) undescribed species are believed to occur on Cyprus and in central Asia. Furthermore, genetic data suggest that Anatolian lake frogs represent neither Rana bedriagae nor Rana ridibunda but a separate undescribed species. Due to several specific characters species status may also be awarded to lake frogs from south-western Anatolia which have already been described as Rana ridibunda caralitana. The results of various phylogenetic analyses speak in favour of a very close phylogenetic relationship between Rana saharica and Rana perezi. Both species are clearly separated from the other water frog species, which fall into two clades. One clade includes (Rana lessonae + Rana bergeri + Rana shqiperica), the second comprises the lake frog species Rana ridibunda, Rana bedriagae, the Asian lake frog group, the Cypriote water frogs. Rana cretensis, and Rana epeirotica. While the phylogenetic relationships within the “pool frog clade” are considered to be clear (there is strong evidence that Rana lessonae and Rana bergeri represent sister species), the relationships within the “lake frog clade” remain largely unresolved. However, in all phylogenetic trees obtained Rana epeirotica, Rana cretensis, and the Cypriote lineage branched off earlier than R. ridibunda, R. bedriagae and the Asian lake frog group and therefore seem to represent phylogenetically older taxa.