Molecular phylogenetic and morphological study of Kohautia (Spermacoceae, Rubiaceae), with the recognition of the new genus Cordylostigma
Por:
Groeninckx I., Ochoterena H., Smets E., Dessein S.
Publicada:
1 oct 2010
Resumen:
Kohautia Cham. & Schltdl. belongs to the predominantly herbaceous Rubiaceae tribe Spermacoceae. Species of Kohautia can easily be distinguished from other Spermacoceae by their monomorphic short-styled flowers in which anthers and stigma are included in the corolla tube, with the stigma always positioned below the anthers. Mainly because of this unique floral morphology. Kohautia was considered to be a distinct genus. Molecular data (atpB-rbcL, petD, rps16, trnL-trnF, ETS, ITS) confirm that the genus is biphyletic. Two distantly related clades correspond to the subgenera Kohautia and Pachystigma Bremek. A similar type of floral organisation thus seems to have evolved twice independently, resulting in similar, but distantly related lineages. In order to translate the biphyletic nature of Kohautia into a formal classification, the two subgenera are recognized at generic level. A substitute name, Cordylostigma Groeninckx & Dessein is proposed for K. subg. Pachystigma because of the existe
Filiaciones:
Groeninckx I.:
Laboratory of Plant Systematics, K.U. Leuven, Kasteelpark Arenberg 31, P.O. Box 2437, 3001 Leuven, Belgium
Ochoterena H.:
Univ Nacl Autonoma Mexico, Inst Biol, Mexico City 04510, DF, Mexico
Smets E.:
Laboratory of Plant Systematics, K.U. Leuven, Kasteelpark Arenberg 31, P.O. Box 2437, 3001 Leuven, Belgium
National Herbarium of the Netherlands, Leiden University Branch, P.O. Box 9514, 2300 RA Leiden, Netherlands
Dessein S.:
National Botanic Garden of Belgium, Domein van Bouchout, 1860 Meise, Belgium
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