Bombina bombina and Bombina variegata in the Mátra mountains (Hungary): New data on distribution and hybridization (Amphibia, Anura, Discoglossidae)

AbstractFire-bellied toads (Bombina bombina and B. variegata) were collected at eight locations in the Mátra mountains and subjected to morphological examinations and electrophoretic investigations of nine enzymes encoded by twelve presumptive loci. Both species occurred together at one place. Another site was inhabited exclusively by B. bombina, while only B. variegata was found at the other localities. Analysis of variation at four marker loci revealed varying degrees of introgression of alien alleles in all populations. Individuals of hybrid origin prevail in most of the B. variegata samples. At Idh-1 and Aat B. variegata exhibits polymorphism for both those electromorphs fixed in northern Carpathian populations of this species and those characteristically found in western parts of its range.