Genetic diversity in the cave beetle genus Darlingtonea: Phylogeography and species limits

Haplotype networks generated from mitochondrial COI sequence data were interpreted using nested cladistic analysis of geographic distances to identify barriers to gene flow and test genetic cohesion of previously hypothesized morphological subspecies of Darlingtonea and Ameroduvalius. Preliminary analysis suggests that factors of cave system size and connectivity may explain patterns of isolation by distance among populations of Darlingtonea.
Results of maximum parsimony and Bayesian analyses of combined molecular data from mitochondrial (COI) and nuclear (wingless, arginine kinase) genes from 110 taxa, including representatives of all five genera of North American cave trechines, are presented. Though individual gene tree topologies differ as expected, all are consistent in finding the widespread, diverse genus Pseudanophthalmus to be paraphyletic. All four "minor" genera (Neaphaenops, Darlingtonea, Nelsonites, and Ameroduvalius) are recovered as monophyletic derived lineages of Pseudanophthalmus, possibly with independent origins.