Kreuzungsexperimente zur Prüfung der Artgrenzen im Genus <i>Lacerta</i> sensu stricto

Abstract

Hybridization Experiments as Tests for Species Boundaries in the Genus Lacerta sensu stricto Hybridization experiments between the five commonly recognized species L. agilis, L. viridis, L. schreiberi, L. strigata, L. trilineata reveal increased rates of malformation and reduced fertility up to sterility as postzygotic isolating mechanisms. Depending on the combination, 30% up to 100% of hybrid females are sterile while only two sterile males were observed among hundreds. In backcrosses and in the rare cases of F 2 generations, a drastic decrease of reproductive success was observed, if fertile offspring occurred. Clear species boundaries between the five species are demonstrated, although different degrees of postzygotic isolation indicate different genetic distances between them. Results from crosses within the taxon L. viridis s. 1. justify the distinction of two polytypic semispecies, L. bilineata in the western part of the range and L. viridis in the eastern part.