Phylogenetic tree based on the Neighbor-Joining method, linearized to show the time of divergence. The scale bar represents the time scale (Kyr) according to the geological calibration proposed by Luchetti et al. (2004). Bootstrap values are given above branches. Clades were scored on the right. C = R. l. corsicus. L = R. lucifugus. S = "sicilian" R. lucifugus. Purple brackets followed by an asterisk mark colonies found in unexpected clades.