Ptiylogeny and floral evolution of the Lysimachieae (Ericales, Myrsi- maceae): evidence from ndhF sequence data

摘要

Earlier hypotheses of floral evolution in Lysimachia and related genera were tested by phylogenetic analysis of DNA sequences from the plastid gene ndhF. It is concluded that taxa with flowers provided with oil-producing trichomes are not advanced andbuzz-pollinated species with anther cone are not ancestral as earlier proposed. Instead, species of Lysimachia with buzz-pollinated flowers belong to one derived clade, species with flowers provided with nectar producing trichomes belong to another, both groups having evolved from yellow flowered oil-producing ancestors. We also show that Lysimachia and most of its subgenera as well as the genera Anagallis, Pelletiera and Asterolinon are paraphyletic or polyphyletic as presently circumscribed, and thatTrientalis and a few American species of Lysimachia are the closest relatives of the other species of Lysimachia + Anagallis, Asterolinon, Pelletiera and Glaux. The subgeneric classification and the biogeographical patterns in the group are briefly discussed.