Phylogenetic relationships of the Hamamelidaceae inferred from sequences of internal transcribed spacers (ITS) of nuclear ribosomal DNA

Intergeneric relationships in the Hamamelidaceae have long been controversi al. In this study, sequences of the internal transcribed spacers of nuclear ribosomal DNA were used to reconstruct the phylogeny for the Hamamelidacea e. Three major clades were recognized in the ITS-based phylogenetic tree: ( 1) Mytilaria-Exbucklandia-Rhodoleia, (2) Disanthus, and (3) the Hamamelidoi deae. Within the Hamamelidoideae there were three well-supported lineages: (1) Corylopsis-Loropetalum-Tetrathyrium-Maingaya-Matudaea, (2) Eustigmateae sensu Endress, plus Molinadendron-Dicoryphinae, and (3) Hamamelis-Fothergi lleae sensu Endress, excluding Matudaea and Molinadendron. The Exbucklandio ideae sensu Endress were not monophyletic, nor were the tribes in the Hamam elidoideae in their current circumscriptions except for the Corylopsideae. Strap-shaped petals, apetaly, and wind pollination have evolved three times independently in the Hamamelidaceae s.s. (Hamamelidaceae minus Altingioide ae), suggesting that homoplasy should be considered in future classificatio ns of the family.