Genetic Analysis of Anatolian Water Frogs Using Mitochondrial and Nuclear Markers

Türkiye has rich amphibian diversity and high biodiversity and is known to be one of the most threatened countries. We analysed 8 Pelophylax ridibundus, 64 Pelophylax bedriagae and 7 Pelophylax caralitanus samples representing Anatolian water frogs in Türkiye using two nuclear and two mitochondrial markers. Among the mitochondrial markers, NADH dehydrogenase 2 (ND2) and cytochrome b (Cytb) revealed a total of 39 and 21 different haplotypes, respectively. The nuclear serum albumin intron 1 (SAI-1) gene region was found to be very important in the assessment of heterozygosity. The rhodopsin (Rhod) gene region was uniform in all samples. Haplotype analyses were performed using DnaSP version 5.10.3. Maximum likelihood estimations and phylogenetic trees were constructed using MEGA 11 software. In this context, ND2 and SAI-1 markers were found to be more efficient in the genetic evaluation of Anatolian water frogs. Two specimens were morphologically identified as Pelophylax caralitanus that genetically identified with the above markers as Pelophylax bedriagae. In addition, four individuals of Pelophylax bedriagae had a nucleotide sequence more closely aligned to Pelophylax caralitanus, as revealed by a comparison of the species-specific bases. These results were further supported by comparing the estimates of mean evolutionary divergence between sequence pairs within the groups. When the analyses were repeated using genetically defined data for ND2, the genetic distance within populations was found to be decreasing. In conclusion, we suggest that morphological taxonomy should be supported by genetic analyses for the most accurate identification of Anatolian water frogs at the species level.