Multilevel studies on the two phenological forms of Large Blue ( Maculinea arion ) (Lepidoptera: Lycaenidae)

The main goal of our research was to study comprehensively the differences between the two phenological forms of the socially parasitic and globally threatened Large Blue ( Maculinea arion ) in the Carpathian Basin using four character sets (mitochondrial sequences, allozymes, male genitalia and wing morphometrics). Comparative analyses of distance matrices, phylogenetic trees and ordination patterns have been applied. The genetic and morphometric patterns revealed by our studies were discordant. While we experienced a significant differentiation between the ‘spring’ and ‘summer type’ of M. arion in both wing and genital traits, the two phenological forms did not show any genetic differentiation on two mitochondrial loci and in allozymes. At the same time, all individuals were infected by Wolbachia . Although certain wing traits may not represent reliable tracers of phylogeny because of the particular adaptive significance, the wing characteristics involved in our research are probably determined genetically. Additionally, the significant differentiation of male genitalia also indicates incipient prezygotic isolation arising from phenological differentiation between the ‘spring and summer arion’. It is possible that all extant differences between the two forms are attributable to (1) different host‐ant use, (2) incipient speciation, (3) cytoplasmatic incompatibility ( CI ) by Wolbachia or the combination of these factors. In addition, discordant results indicate that the combined use of different approaches and data sets is strictly necessary to clarify systematic and evolutionary relationships.