Significance of palynology for phylogeny of Annonaceae: Experiments with removal of pollen characters

Phylogenetic analyses based on morphology place Anaxagorea and other taxa with granular monosulcate pollen, as in other Magnoliales, at the base of Annonaceae. Taxa with columellar tetrads, granular tetrads, and inaperturate monads form a derived clade. To test the systematic importance of palynology, we analyzed the data set with pollen characters removed. The result was lower resolution and a different rooting of the family, between Uvariopsis and other groups with columellar tetrads. Anaxagorea and other monosulcates are higher in the tree, implying that granular monosulcate pollen, laminar stamens, and irregular endosperm ruminations are reversals. This rooting is highly unparsimonious when pollen characters are included, and only weakly supported over the Anaxagorea rooting when pollen is excluded. Together with preliminary molecular analyses, these experiments confirm the special value of palynology in systematics of Annonaceae.