title: Molecular phylogenetics reveals Leontodon (Asteraceae, Lactuceae) to be diphyletic.
abstract: The plastid matK gene, trnL/F spacer, and nuclear rDNA ITS were sequenced for 36 species of Leontodon and 29 taxa of related genera of tribe Lactuceae. Phylogenetic relationships inferred from the independent and combined data are largely congruent and reveal that Leontodon sensu lato (s.l.) as presently defined is diphyletic: L. subgenus Leontodon forms a clade with Helminthotheca, Picris and Hypochaeris as sister genera, whereas L. subgenus Oporinia appears as a separate clade with strong bootstrap support and is thus better treated as a separate genus. Previous sectional classifications of Leontodon s.l. are considered in the light of DNA and additional morphological and karyological data. Support is presented for a core group of Hypochaeridinae sensu stricto (s.s.) with the two clades of Leontodon s.l., Helminthotheca, Picris, and Hypochaeris, whereas Urospermum, Hyoseris, Aposeris, and Rhagadiolus appear to be positioned more distantly.
authors.affiliation: Department of Systematic and Evolutionary Botany, University of Vienna, Rennweg 14, A-1030 Austria;
authors.forename: Rosabelle
authors.initials: R
authors.lastname: Samuel
authors.forename: Walter
authors.initials: W
authors.lastname: Gutermann
authors.forename: Tod F
authors.initials: TF
authors.lastname: Stuessy
authors.forename: Claudete F
authors.initials: CF
authors.lastname: Ruas
authors.forename: Hans-Walter
authors.initials: HW
authors.lastname: Lack
authors.forename: Karin
authors.initials: K
authors.lastname: Tremetsberger
authors.forename: Salvador
authors.initials: S
authors.lastname: Talavera
authors.forename: Barbara
authors.initials: B
authors.lastname: Hermanowski
authors.forename: Friedrich
authors.initials: F
authors.lastname: Ehrendorfer