The central Alps comprise a major dispersal barrier between western and eastern populations of two butterfly species

Aim Genetic connectivity and diversity are key components of species' resilience to environmental change. However, the specific factors shaping poorly understood. We here aim strengthen our understanding in two butterfly species, by identifying regions high genetic barriers dispersal. Location European Alps. Taxon Copper butterflies (Lycaena spp.). Methods sampled 21 Lycaena hippothoe 14 L. virgaureae populations with 18 individuals each Using 9 microsatellite markers, respectively, we analysed population structure (using arlequin, genalex, snmf). spatial patterns gene flow an estimated effective migration surface), demographic history size (diyabc), habitat suitability (maxent), isolation distance, resistance (genalex, circuitscape). Results found higher a more pronounced than virgaureae. Both species displayed major barrier central Western eastern showed highest hippothoe, but ones Populations both were structured geodetic minimum maximum altitude. Main Conclusions The seemed be strongly affected history, demography geographic features. Valleys mountain ridges seem comprise dispersal barriers. seems related low ability closed local abundances as opposed suggest that different conservation strategies needed for these closely focussing on connecting suitable habitats increasing sizes