02320nas a2200265   4500008004100000020001400041245010800055210006900163250001500232300001000247490000700257520148200264653002401746653001701770653003801787653001401825653001201839653001401851100002301865700002501888700002101913700002001934700002401954856007601978       2013                        eng d  a1055-790300aMolecular phylogenetics and morphological evolution of St. John's wort (<i>Hypericum</i>; Hypericaceae)0 aMolecular phylogenetics and morphological evolution of St Johns   a08.09.2012  a1--160 v663 a<p>Phylogenetic hypotheses for the large cosmopolitan genus Hypericum (St. John&sbquo;&Auml;&ocirc;s wort) have previously been based on morphology, and molecular studies have thus far included only a few species. In this study, we used 360 sequences of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) for 206 species representing Hypericum (incl. Triadenum and Thornea) and three other genera of Hypericaceae to generate an explicit phylogenetic hypothesis for the genus using parsimony and model-based methods. The results indicate that the small genus Triadenum is nested in a clade within Hypericum containing most of the New World species. Sister to Hypericum is Thornea from Central America. Within Hypericum, three large clades and two smaller grades were found; these are based on their general morphology, especially characters used previously in taxonomy of the genus. Relative to the most recent classification, around 60% of the sections of Hypericum were monophyletic. We used a Bayesian approach to reconstruct ancestral states of selected morphological characters, which resulted in recognition of characters that support major clades within the genus and a revised interpretation of morphological evolution in Hypericum. The shrubby habit represents the plesiomorphic state from which herbs evolved several times. Arborescent species have radiated convergently in high-elevation habitats in tropical Africa and South America.</p>
10aCharacter evolution10aHypericaceae10aInternal transcribed spacer (ITS)10aPhylogeny10aThornea10aTriadenum1 aNürk, Nicolai, M.1 aMadriñán, Santiago1 aCarine, Mark, A.1 aChase, Mark, W.1 aBlattner, Frank, R.  uhttp://www.sciencedirect.com/science/article/pii/S1055790312003314?v=s5