XVI International Botanical Congess

Cobaea comprises 18 species of neotropical vines with remarkable floral diversity. There were significant incongruences between phylogenies based on ITS and morphological characters in the placement of two taxa. The chloroplast trnT-trnL and trnL-trnF spacers were sequenced from Cobaea species to gain further insight into the causes of these differences. Strict consensus trees resulting from analyses of each spacer and the combined spacer data were highly congruent with each other and with the previous analysis of ITS sequences. The sister group relationship of sections Pachysepalae and Rosenbergia is supported by the molecular data. Comparisons of the phylogenies suggest that floral lability and either introgression or lineage sorting have played an important role in the evolution of Cobaea.