Groups of recent speciation are characterized by high levels introgression and gene flow, which often confounds delimitation species on a DNA basis. We analyzed nuclear sequences (ETS spacer the AGT1 gene) obtained from large sample C. calocephala complex Balkan clade Centaurea sect. Acrocentron (Compositae, Cardueae-Centaureinae) together with wide representation other section. Our main goals ...