XVI International Botanical Congess

Analysis of a combined data set of 18S rDNA, rbcL, and atpB sequences for 567 species resulted in a highly resolved and well-supported topology for angiosperms. Much of the spine of the tree and most large clades receive jackknife support >50%. Amborellaceae, Nymphaeaceae, and a clade of Austrobaileyaceae, Illiciaceae, and Schisandraceae are successive sisters to all other angiosperms. Most monosulcates form a weakly supported clade. Ceratophyllaceae are sister to a well-supported eudicot clade. Lower eudicots form a grade, followed by a core eudicot clade that comprises six well-supported subclades: 1) Berberidopsidaceae/Aextoxicaceae, 2) Myrothamnaceae/Gunneraceae, 3) Saxifragales (Vitaceae, eurosids), 4) Santalales, 5) Caryophyllales/Dilleniaceae, 6) asterids.