Differences in genetic variability between two ecotypes of the endangered myrmecophilous butterfly Phengaris (=Maculinea) alcon– the setting of conservation priorities

. 1. The endangered butterfly Phengaris alcon exists in two ecotypes ( P. ‘alcon’ and P. ‘rebeli’ ), which inhabit contrasting biotopes (wet and warm/dry grasslands respectively) and use different larval food plants. The initially flower‐bud‐feeding caterpillars complete their development as social parasites of Myrmica ants, and the specificity of these relationships shows geographical variation. 2. We studied the genetic structure of 16...