Phylogeny of subtribe Gentianinae (Gentianaceae): biogeographic inferences despite limitations in temporal calibration points
Détails
ID Serval
serval:BIB_2C3FE07AE86C
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Phylogeny of subtribe Gentianinae (Gentianaceae): biogeographic inferences despite limitations in temporal calibration points
Périodique
Taxon
ISSN
0040-0262
Statut éditorial
Publié
Date de publication
2010
Peer-reviewed
Oui
Volume
59
Numéro
6
Pages
1701-1711
Langue
anglais
Résumé
The subtribe Gentianinae comprises ca. 425 species, most of them within the well-studied genus Gentiana and mainly distributed over the Eurasian continent. Phylogenetic relationships between Gentiana and its closest relatives, the climbing gentians (Crawfurdia, Tripterospermum) and the new genus Metagentiana, remain unclear. All three genera were recently found to be polyphyletic, possibly because of poor sampling of Tripterospermum and Crawfurdia. Highest diversity of Gentianinae occurs in the western Himalaya, but the absence of uncontroversial fossil evidence limits our understanding of its biogeography. In the present study, we generated ITS and atpB-rbcL sequences for 19 species of Tripterospermum, 9 of Crawfurdia and 11 of Metagentiana, together representing about 60 percent of the species diversity of these genera. Our results show that only Metagentiana is polyphyletic and divided into three monophyletic entities. No unambiguous synapomorphies were associated with the three Metagentiana entities. Different combinations of three approximate calibration points were used to generate three divergence time estimation scenarios. Although dating hypotheses were mostly inconsistent, they concurred in associating radiation of Gentiana to an orogenic phase of the Himalaya between 15 and 10 million years ago. Our study illustrates the conceptual difficulties in addressing the time frame of diversification in a group lacking sufficient fossil number and quality.
Mots-clé
Asia, atpB-rbcL, biogeography, Gentianinae, ITS, molecular dating, molecular phylogeny
Web of science
Création de la notice
03/09/2010 0:04
Dernière modification de la notice
20/08/2019 13:11