Molecular and phytochemical systematics of the subtribe Hypochaeridinae (Asteraceae, Cichorieae)

• Published in: Organisms diversity & evolution 2012-03, Vol.12 (1), p.1-16
• Main Authors: Enke, Neela, Gemeinholzer, Birgit, Zidorn, Christian
• Format: Article
• Language: English
• Subjects: Acids; Animal Systematics/Taxonomy/Biogeography; Asteraceae; Biodiversity; Biomedical and Life Sciences; Caffeic acid; Developmental Biology; Evolutionary Biology; Flavonoids; Hedypnois; Hypochaeris; Lactones; Leontodon; Life Sciences; Original Article; Phylogenetics; Phytochemicals; Plant Systematics/Taxonomy/Biogeography; Sesquiterpene lactones; Systematics
• ISSN: 1439-6092; 1618-1077
• DOI: 10.1007/s13127-011-0064-0

The systematics of the Hypochaeridinae subtribe was re-evaluated based on a combination of published and new molecular data. Newly found clades were additionally characterized using published and new phytochemical data. In addition to flavonoids and sesquiterpene lactones, which had been reviewed recently as chemosystematic markers in the Cichorieae, we analysed the reported occurrences of caffeic acid derivatives and their potential as chemosystematic markers. Our molecular results required further changes in the systematics of the genus Leontodon . Based on previous molecular data, Leontodon s.l.—i.e. including sections Asterothrix , Leontodon , Thrincia , Kalbfussia , and Oporinia (Widder 1975 )—had been split into the genera Leontodon s.str. (sections Asterothrix , Leontodon , and Thrincia ) and Scorzoneroides (sections Kalbfussia and Oporinia ). Instead of splitting Leontodon into even a higher number of segregate genera we propose to include Hedypnois into Leontodon s.str. and here into section Leontodon. Moreover, sections Asterothrix and Leontodon should be merged into a single section Leontodon . The newly defined genus Leontodon is characterised by the unique occurrence of hydroxyhypocretenolides. The monophyly of the genus Hypochaeris is neither supported nor contradicted and potentially comprises two separate molecular clades . The clade Hypochaeris I comprises the majority of the European and Mediterranean as well as all South American taxa of Hypochaeris s.l. while the clade Hypochaeris II encompasses only H. achyrophorus L., H. glabra L., H. laevigata Benth. & Hook.f., and H. radicata L.