Fig. 2

Cluster analyses performed on MLGs of Pelophylax individuals based on microsatellite loci. a Bar plot of 17 microsatellite loci from Bayesian cluster analysis performed in Structure (K = 2). Each vertical line represents one individual, each color represents the species specificity of alleles to one of the parental genomes (green = P. lessonae genome, red = P. ridibundus genome), and each cluster represents a different genotype (cluster 1 = LL, cluster 2 = RL, cluster 3 = RR). b Principal component analysis (PCA) of 17 microsatellite loci performed in GenAlEx. Each point represents an individual MLG, each color and symbol a group of related MLGs (according to allele sharing). Group red diamonds—R (RR from R-E) represents P. ridibundus from R-E system; group blue squares—R (RL from R-E) represents ridibundus genomes of P. esculentus from the R-E system; group yellow circles—L (RL from R-E) represents lessonae genomes of P. esculentus from the R-E system; group green triangles—L (LL from L-E) represents P. lessonae from the L-E system; group violet diamonds—L (RL from L-E) represents lessonae genomes of P. esculentus from the L-E system. Inset screenshot shows the eigenvalues for each axis as principle components of the analysis. c UPGMA tree computed with the program Populations using DA distances which were calculated on the basis of 10 microsatellite loci. Numbers on branches (with or without arrows) indicate bootstrap values > 50%. Each terminal unit represents one individual: green color—L clade represents P. lessonae from the L-E system; yellow color—L hemiclone represents lessonae genomes of P. esculentus from the R-E system; red color—R clade represents P. ridibundus from the R-E system; blue color—R clade represents ridibundus genomes of P. esculentus from the R-E system; violet color—P. kurtmuelleri individual. Detailed information is given in Additional file 6: Figure S1