“…However, because such comparative studies are time-consuming and the systematic classifi cation has diff erent hierarchical levels, they can only be done in a stepwise fashion (for eudicots, e.g. Matthews and Endress, 2002, 2005a, b , 2006von Balthazar et al, 2004 ;Sch ö nenberger and Grenhagen, 2005 ;Endress and Matthews, 2006 ;Ronse De Craene and Haston, 2006 ;von Balthazar et al, 2006 ;Endress, 2008 , 2009 ;Janka et al, 2008 ;Sch ö nenberger, 2009 ;von Balthazar and Sch ö nenberger, 2009 ;Sch ö nenberger et al, 2010 ).…”