title: 9-genes reinforce the phylogeny of holometabola and yield alternate views on the phylogenetic placement of Strepsiptera.
abstract: BACKGROUND
  The extraordinary morphology, reproductive and developmental biology, and behavioral ecology of twisted wing parasites (order Strepsiptera) have puzzled biologists for centuries. Even today, the phylogenetic position of these enigmatic "insects from outer space" [1] remains uncertain and contentious. Recent authors have argued for the placement of Strepsiptera within or as a close relative of beetles (order Coleoptera), as sister group of flies (order Diptera), or even outside of Holometabola.
  
  
  RESULTS
  Here, we combine data from several recent studies with new data (for a total of 9 nuclear genes and approximately 13 kb of aligned data for 34 taxa), to help clarify the phylogenetic placement of Strepsiptera. Our results unequivocally support the monophyly of Neuropteroidea (=Neuropterida+Coleoptera)+Strepsiptera, but recover Strepsiptera either derived from within polyphagan beetles (order Coleoptera), or in a position sister to Neuropterida. All other supra-ordinal- and ordinal-level relationships recovered with strong nodal support were consistent with most other recent studies.
  
  
  CONCLUSIONS
  These results, coupled with the recent proposed placement of Strepsiptera sister to Coleoptera, suggest that while the phylogenetic neighborhood of Strepsiptera has been identified, unequivocal placement to a specific branch within Neuropteroidea will require additional study.
authors.affiliation: Department of Biological Sciences, University of Memphis, Memphis, Tennessee, United States of America. dmckenna@memphis.edu
authors.forename: Duane D
authors.initials: DD
authors.lastname: McKenna
authors.forename: Brian D
authors.initials: BD
authors.lastname: Farrell
mesh_terms: D000818:Animals; D019476:Insect Proteins / Q000235:genetics; D007313:Insecta / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics*; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D019476:Insect Proteins