title: Climate oscillations, glacial refugia, and dispersal ability: factors influencing the genetic structure of the least salmonfly, Pteronarcella badia (Plecoptera), in Western North America.
abstract: Phylogeographic studies of aquatic insects provide valuable insights into mechanisms that shape the genetic structure of communities, yet studies that include broad geographic areas are uncommon for this group. We conducted a broad scale phylogeographic analysis of the least salmonfly Pteronarcella badia (Plecoptera) across western North America. We tested hypotheses related to mode of dispersal and the influence of historic climate oscillations on population genetic structure. In order to generate a larger mitochondrial data set, we used 454 sequencing to reconstruct the complete mitochondrial genome in the early stages of the project.
  
  
  
  Our analysis revealed high levels of population structure with several deeply divergent clades present across the sample area. Evidence from five mitochondrial genes and one nuclear locus identified a potentially cryptic lineage in the Pacific Northwest. Gene flow estimates and geographic clade distributions suggest that overland flight during the winged adult stage is an important dispersal mechanism for this taxon. We found evidence of multiple glacial refugia across the species distribution and signs of secondary contact within and among major clades.
  
  
  
  This study provides a basis for future studies of aquatic insect phylogeography at the inter-basin scale in western North America. Our findings add to an understanding of the role of historical climate isolations in shaping assemblages of aquatic insects in this region. We identified several geographic areas that may have historical importance for other aquatic organisms with similar distributions and dispersal strategies as P. badia. This work adds to the ever-growing list of studies that highlight the potential of next-generation DNA sequencing in a phylogenetic context to improve molecular data sets from understudied groups.
authors.affiliation: Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR, 97333, USA. johnssproul@gmail.com.
authors.forename: John S
authors.initials: JS
authors.lastname: Sproul
authors.affiliation: Department of Ecology, Evolution and Organismal Biology, 251 Bessey Hall, Ames, IA, 50011, USA. derek.d.houston@gmail.com.
authors.forename: Derek D
authors.initials: DD
authors.lastname: Houston
authors.affiliation: Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA. rileynelson@byu.edu.|M.L Bean Life Science Museum, Brigham Young University, 645 East 1430 North, Provo, UT, 84602, USA. rileynelson@byu.edu.
authors.forename: C Riley
authors.initials: CR
authors.lastname: Nelson
authors.affiliation: Department of Microbiology and Molecular Biology, Brigham Young University, 4007 Life Science Building, Provo, UT, 84602, USA. evansp@byu.edu.
authors.forename: R Paul
authors.initials: RP
authors.lastname: Evans
authors.affiliation: Computational Biology Institute, George Washington University, Innovation Hall, Ashburn, VA, 20147, USA. kcrandall@gwu.edu.
authors.forename: Keith A
authors.initials: KA
authors.lastname: Crandall
authors.affiliation: Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA. Dennis_Shiozawa@byu.edu.|M.L Bean Life Science Museum, Brigham Young University, 645 East 1430 North, Provo, UT, 84602, USA. Dennis_Shiozawa@byu.edu.
authors.forename: Dennis K
authors.initials: DK
authors.lastname: Shiozawa
mesh_terms: D000818:Animals; D002980:Climate; D004272:DNA, Mitochondrial / Q000235:genetics; D051456:Gene Flow; D014644:Genetic Variation; D005828:Genetics, Population; D007313:Insecta / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D009656:North America; D015205:Northwestern United States; D058974:Phylogeography; D000068236:Refugium
chemical_list: D004272:DNA, Mitochondrial