Comparison of genetic patterns between European and Asian populations of an endangered butterfly species

Less transformed and managed grassland habitats in Asia serve as a good frame of reference for studies on demographics and ecological situations of grassland species in Europe. In this study, using AFLPs (transposon insertion display), we compared the genetic structures of populations of the endangered and highly specialised scarce large blue (Phengaris teleius, Bergstrasser, 1779) butterfly from Europe (Germany, Poland, and Ukraine) and Asia (Siberia and Mongolia). There are no differences in levels of intra-population genetic variability between European and AsianP. teleiuspopulations. Nevertheless, we found significantly higher genetic differentiation (wider scattering) among European populations than among Asian populations. All examined Eurasian populations were admixed, except for those from the Bavarian region (Germany) where an atypical genetic structure was observed forP. teleius. Individual membership probabilities to a population were higher and more variable among European populations than among Asian populations. Comparison of genetic spatial structures revealed an isolation-by-distance effect in both European and Asian populations. Genetic autocorrelation analysis showed that significant dissimilarity among individuals first appeared at a distance of 1800 km at Asian sites, but at only 400 km at European sites. The observedP. teleiusgenetic structure reveals substantial differences in the quality of connectivity among European and Asian populations, which favour Asian populations. It suggests that differences between European and AsianP. teleiuspopulation genetic structures have the origin in differences in habitat structures, emphasising the impact of habitat fragmentation on animal movement in Europe.

Automated summary

The study shows genetic differences between European and Asian populations of the scarce large blue butterfly, with higher differentiation among European populations. There is an isolation-by-distance effect in both European and Asian populations, with better connectivity in the Asian populations. These differences may originate from variations in habitat structures, highlighting the impact of habitat fragmentation on animal movement in Europe.