Intraspecific Diversity and Phylogeography in SouthernAppalachian Dasycerus carolinensis (Coleoptera:Staphylinidae: Dasycerinae)

摘要

The southern Appalachian Mountains in eastern North America host exceptional diversity, a substantial proportionof which has been generated in place. Yet, beyond broad generalities, bio- and phylogeographicalpatterns, and the temporal scale of diversification in the region are poorly resolved. Using one mitochondrialand one nuclear marker, we analyze intraspecific diversity patterns in a flightless, litter-inhabiting rove beetleDasycerus carolinensis Horn. Our goals were to reconstruct the phylogeographical history of this species, producinga dated intraspecific phylogeny, and to examine previous hypotheses of possible cryptic divergenceacross populations of the species. Samples derive from a mix of old-growth fragments and secondary growthforests, and we also ask whether old-growth remnants host a larger proportion of genetic diversity in thespecies. We recover a strong primary subdivision among major lineages across the French Broad River basin(dated to ~5.8 MYBP), and a secondary subdivision among western populations dating to ~4.5 MYBP. Mostinterpopulation uncorrected divergences exceed 5%, strongly suggesting cryptic differentiation. Old-growthpopulations do not show greater genetic diversity than secondary-growth populations, indicating that mostpopulations have persisted through recent anthropogenic disturbance.