Phylogeny and evolution of the S outh A frican genus M etalasia ( A steraceae– G naphalieae) inferred from molecular and morphological data

M etalasia is a genus in tribe G naphalieae ( A steraceae), endemic to S outh A frica and with its main distribution in the C ape F loristic R egion. The genus comprises 57 species and, with a number of closely related genera, it constitutes the ‘ M etalasia clade’. A species‐level phylogenetic analysis is presented, based on DNA sequences from two nuclear (internal and external transcribed spacer: ITS , ETS ) and two plastid ( psbA‐trnH , trnL‐trnF ) regions together with morphological data. Analyses combining molecular and morphological data attempt not only to resolve species interrelationships, but also to detect patterns in character evolution. Phylogenetic analyses corroborate our earlier study and demonstrate that M etalasia is formed of two equally sized, well‐supported sister groups, one of which is characterized by papillose cypselas. The results differ greatly from earlier hypotheses based on morphology alone, as few morphological characters support the phylogenetic patterns obtained. The two clades of M etalasia do, however, appear to differ in distribution, corresponding to the different rainfall regimes of S outh A frica. Analyses show a few taxa to be problematic; one example is the widely distributed M . densa which appears to be an intricate species complex. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society , 2014, 174 , 173–198.