02320nas a2200265 4500008004100000020001400041245010800055210006900163250001500232300001000247490000700257520148200264653002401746653001701770653003801787653001401825653001201839653001401851100002301865700002501888700002101913700002001934700002401954856007601978 2013 eng d a1055-790300aMolecular phylogenetics and morphological evolution of St. John's wort (Hypericum; Hypericaceae)0 aMolecular phylogenetics and morphological evolution of St Johns  a08.09.2012 a1--160 v663 a

Phylogenetic hypotheses for the large cosmopolitan genus Hypericum (St. John’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.

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=s501944nas a2200217 4500008004100000245008600041210006900127300001400196490000700210520126900217653000901486653001701495653002301512653001401535653001401549653001401563653002201577100002301599700002101622856008301643 2010 eng d00aCladistic analysis of morphological characters in Hypericum (Hypericaceae)0 aCladistic analysis of morphological characters in iHypericumi Hy a1495-15070 v593 a

Hypericum is a worldwide distributed genus with almost 500 species, including the medically used apomictic species H. perforatum. It is one of the few large plant genera where alpha taxonomy is nearly completed. To conduct a formal cladistic analysis of the genus, we coded 89 morphological characters for all described taxa, and analyzed the data with parsimony and Bayesian methods. The obtained trees indicate Hypericum to be monophyletic, if the monotypic genus Santomasia is included, and Lianthus as the sister group. The arrangement of the remaining genera of Hypericaceae included in the analysis is in congruence with molecular phylogenies. Apomorphic characters supporting the relationships of the genera are pointed out. The cladistic analysis revealed four groups within Hypericum: a basal grade containing Mediterranean species and three big clades containing most of the diversity of the genus. The borders of the Mediterranean Sea as part of the late Tethys Ocean are hypothesized as a probable area of origin for the genus. As indicated in the presented tree, a shrubby habit appears to be the ancestral state within Hypericum from which trees and herbs evolved, and apomixis originated at least three times independently within the genus.

10a_nmn10abiogeography10acladistic analysis10aevolution10aHypericum10aPhylogeny10aSt. John’s wort1 aNürk, Nicolai, M.1 aBlattner, F., R. uhttp://www.ingentaconnect.com/content/iapt/tax/2010/00000059/00000005/art00014