title: Heteroploid Knautia drymeia includes K. gussonei and cannot be separated into diagnosable subspecies.
abstract: Knautia drymeia is a morphologically variable, diploid and tetraploid temperate forest understory species distributed in southeastern Europe and adjacent areas. The species is an excellent system to explore the influence of polypoidy on taxonomic delineations, the role of hybridization among genetically distant populations in polyploid evolution, and the impact of glacial refugia on the evolution of polyploids.
  
  
  
  Amplified fragment length polymorphism fingerprinting and multivariate analyses of morphological characters were performed on 57 populations spanning the distribution area of K. drymeia. K-means clustering, comparison of in-silico tetraploids and observed tetraploids, and a phylogeographic analysis using relaxed random walks were used to explore the genetic structure within the diploids, to infer the origin of the tetraploids and to reconstruct range expansion through time. Further, we contrasted the morphology and genetic groups with current taxonomy and evaluated the status of the tetraploid Apennine endemic K. gussonei and the intraspecific taxa of K. drymeia.
  
  
  
  The genetic structure was strongly geographically correlated and yielded four genetic groups; K. gussonei was inseparable from K. drymeia. Distributions of diploid lineages are suggestive of glacial refugia in the northwesternmost and southeastern Balkan Peninsula. Polyploids originated at least two times, as autopolyploids and probably additionally also as allopolyploids. Morphological divergence corresponded with neither genetic groups nor current taxonomy.
  
  
  
  Genetic and morphometric data confirmed neither divergence of K. gussonei nor recognition of subspecies within K. drymeia. We therefore propose treating K. drymeia as a morphologically and genetically variable species without infraspecific taxa.
authors.affiliation: Faculty of Science, University of Zagreb, Marulićev trg 20/II, HR-10000 Zagreb, Croatia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Rešetnik
authors.affiliation: Institute of Botany, University of Innsbruck, Sternwartestraße 15, A-6020 Innsbruck, Austria.
authors.forename: Božo
authors.initials: B
authors.lastname: Frajman
authors.affiliation: Institute of Botany, University of Innsbruck, Sternwartestraße 15, A-6020 Innsbruck, Austria peter.schoenswetter@uibk.ac.at.
authors.forename: Peter
authors.initials: P
authors.lastname: Schönswetter
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D005075:Biological Evolution; D027922:Caprifoliaceae / Q000145:classification* / Q000235:genetics; D004171:Diploidy; D005828:Genetics, Population; D058974:Phylogeography; D011003:Ploidies; D011123:Polyploidy
keywords: AFLP; Caprifoliaceae; allopolyploidy; autopolypolyploidy; continuous geographic analysis; forest understory plant; glacial refugia; morphometrics; polyploids; taxonomy