Estimating the divergence time between LeConte and Thomas and Bright

The complex taxonomic relationship between the species of genus Dendroctonus is due to very similar morphology as well as their overlapping geographic distribution. These provide an opportunity to study the influence of past geologic events on their pattern of diversification and speciation. As the phylogenetic reconstruction by Kelly and Farrell (1998) using mtDNA cytochrome oxidase I sequences shown a close relationship between and , our goal was estimating the time to most recent common ancestor (TMRCA) between these species and to infer the possible historic and demographic events that promote their divergence. For this purpose we have analyzed mtDNA COI sequences, 114 haplotipes for of 486 pb long and of 70 . We have compared two statistical methods of estimating the time TMRCA which has been proposed by Nielsen and Wakeley (2001) and Tang et al. (2002). The results obtain on both methods suggest that the divergence between these species is close to the early Pleistocene in conditions of sympatric as result of the climatic changes occurred during the glaciations of this period.