New information forIlexphylogenetics based on the plastidpsbA-trnHintergenic spacer (Aquifoliaceae)

The aim of the present work was to clarify the origin and phylogenetic position of the species belonging to the genus Ilex (Aquifoliaceae), especially the South American species. Phylogenetic relationships of the genus Ilex were investigated using the plastid psbA-trnH intergenic spacer and parsimony and Bayesian analyses. The psbA-trnH intergenic spacer was shown to evolve slowly within Ilex, but a major gap present in this region was useful in the phylogenetic study of the genus. To obtain more potentially parsimonious characters, atpB-rbcL intergenic spacer data were combined with those for psbA-trnH. Many gaps present in the psbA-trnH region were useful in the phylogenetic study of the genus Ilex. The topology of the trees showed that, in general, the clades are strongly related to geographical areas, a fact especially evident in certain different Asian lineages.