Population structure of Acrotrichis xanthocera (Matthews) (Coleoptera: Ptiliidae) in the Klamath Ecoregion of northwestern California, inferred from mitochondrial DNA sequence variation

The Klamath-Siskiyou Ecoregion of northern California and southern Oregon has extremely high biodiversity, but conservation centers on the protection of habitat for the northern spotted owl. A network of late successional reserves has been established without consideration of potential for protecting overall biodiversity, including genetic diversity. Mitochondrial DNA sequences are used to examine the population structure of Acrotrichis xanthocera (Coleoptera: Ptiliidae) sampled from five late successional reserves within the Klamath-Siskiyou Ecoregion and five comparison sites from northern California. Measures of gene flow, phylogenetic analysis, and nested clade analysis are employed to infer historical demographic and phylogeographic processes. Results show that A. xanthocera populations have undergone past range expansion, but gene flow is currently limited. Individual late successional reserves do not adequately protect the genetic variation in this species. Although further research is needed, these results are likely to be congruent for other edaphic arthropod species. Improvement of the late successional reserve system is warranted for maximum protection of the genetic diversity of soil arthropod populations.