Molecular phylogeny of the goldenasters, subtribe Chrysopsidinae (Asteraceae: Astereae), based on nuclear ribosomal and chloroplast sequence data

Abstract

In this study, phylogenies were estimated based on molecular data from ETS and ITS, nuclear ribosomal DNA, and ycf1 and psbA-trnH, chloroplast DNA for all known genera of the Chrysopsidinae. The resulting phylogenies were used as the basis for addressing questions related to subtribal and generic monophyly, the relationship of the Central and South American genera Osbertia, Tomentaurum, and Noticastrum to North American genera, biogeography, morphological trait evolution and convergence among morphological features commonly used to delimit generic and species boundaries. Additionally, modifications to commonly used DNA extraction techniques allowed us to access DNA from relatively old herbarium specimens. Results from analyses of individual and combined datasets support the monophyly of the Chrysopsidinae and allowed some resolution of both the relationships among the genera of the Chrysopsidinae and the relationships among sections of the genus Heterotheca.