This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.
Molecular Phylogeny of Subgenus Polypompholyx (Utricularia; Lentibulariaceae) based on three plastid markers: Diversification and Proposal for a New Section
Phylogenetic relationships among all of the 47 recognised species and eight putative new taxa of Utricularia subgenus Polypompholyx, were assessed using maximum parsimony and Bayesian inference analyses of DNA sequences representing the plastid rps16 intron, trnL-F intron and spacer regions and the trnDT intron. We found strong jackknife and posterior probability support for a monophyletic subgenus Polypompholyx and a sister relationship between the sections Polypompholyx + Tridentaria and Pleiochasia. Within the section Pleiochasia are two well-supported major clades each containing three supported sub-clades. Our S-DIVA biogeographic analysis, using five major Australian drainage basins and New Zealand as geographic areas, estimated two early vicariance events between south western and north western mainland regions, corresponding with known periods of increased aridity at 15 and five Ma. Subsequent dispersal events were estimated between north and south eastern Australia, with recent dispersal of species from south western regions to the south east and New Zealand occurring between 4–1 Ma. There were 28 speciation events inferred within the north western region, followed by nine for the south west and south eastern regions, indicating that the north western monsoonal savannah habitats are a biodiversity hotspot for the lineage. We also show the evolutionary shifts in in growth habit, and show that lifecycle corresponds strongly with shifts in seasonality between temperate and monsoonal regions. Based on our molecular phylogenetic results and morphology, we here designate a new sectional ranking for subg. Polypompholyx.
SB17003 Accepted 12 July 2017
© CSIRO 2017