XVI International Botanical Congess
Recent phylogenetic studies resolve Acorus, Alismatanae, and Aranae (approximately as circumscribed by Dahlgren, Clifford, and Yeo, 1995, Families of Monocotyledons) as early-diverging lineages within the monocots, but differ in the precise relationships resolved among these three groups and a fourth that includes all other monocots. In the latter group, a clade that includes Arecanae, Bromelianae, Commelinanae, and Zingiberanae (the ABCZ clade), and a clade that includes Cyclanthanae, Pandananae, and Velloziaceae (of Bromelianae) are nested among elements of a nonmonophyletic Lilianae. Current work on the higher-level structure of the monocots is focused on the Lilianae and on the ABCZ clade, within which Arecanae and Zingiberanae appear to be monophyletic, and Bromelianae and Commelinanae do not.