Species and mate recognition in two sympatric Grayling butterflies: Hipparchia fagi and H. hermione genava (Lepidoptera)

Abstract

The main aim of this study was to investigate and compare the patterns of male courtship behaviour in Hipparchia fagi (Woodland Grayling) and H. hermione genava (Rock Grayling) in order to determine if premating barriers are involved in the reproductive isolation between the two sympatric and syntopic species. Although they show a similar pattern of sexual behaviour (perching, flight pursuit, courtship), there were significant quantitative inter-specific differences in the step Bowing. During this step, the male bashes and strokes the female antennae between his forewings on the androconial scales revealing the importance of scent stimuli in mate communication. Moreover, different signals, spanning several sensory modalities (visual, chemical, tactile stimuli) and spatio-temporal scales (during the pair flight and the courtship step), might serve as premating barriers between the two species. In particular, both males and females of H. fagi (a woodland habitat specialist) seem to take less time in recognising their conspecific partner, while H. hermione males need to spend more time in courting (and identifying) the “right” females.