Parsing polyphyletic Pueraria: Delimiting distinct evolutionary lineages through phylogeny.

Several taxonomic and phylogenetic studies have hypothesized polyphyly within Pueraria DC., a genus comprising 19 species (24 with varieties) including the highly invasive Pueraria montana var. lobata (Kudzu) introduced to the U.S.A. about 150years ago. Previous efforts to investigate monophyly of the genus have been hampered by limited taxon sampling or a lack of comprehensive evolutionary context that would enable definitive taxonomic associations. This work presents a comprehensive phylogenetic investigation of Pueraria within the context of tribe Phaseoleae (Leguminosae). Polyphyly was found to be more extensive than previously thought, with five distinct lineages spread across the tribe and spanning over 25mya of divergence strongly supported by two chloroplast and one nuclear marker, AS2, presented here as a phylogenetic marker for the first time. Our phylogenies support taxonomic revisions to rectify polyphyly within Pueraria, including the resurrection of Neustanthus, moving one species to Teyleria, and the creation of two new genera, Haymondia and Toxicopueraria (taxonomic revisions published elsewhere).