A Preliminary Molecular Phylogeny of theAbaremaAlliance (Leguminosae) and Implications for Taxonomic Rearrangement

Abstract

Premise of research. Here we present the first molecular phylogeny of the Abarema alliance, based on a large species sampling from across its geographical range. Our aim was to test the monophyly of the alliance and to analyze the major biogeographical patterns throughout the Neotropics.Methodology. DNA sequence data were derived from the chloroplast matK region and nuclear external transcribed spacers (ETSs) and were phylogenetically analyzed in order to resolve systematic relationships.Pivotal results. Our results agree in part with Barneby and Grimes’s circumscription of the alliance, including the genera Hydrochorea and Balizia and part of Abarema. However, Abarema, the largest genus within the alliance, is polyphyletic. The type species of Abarema, Abarema cochliacarpos, is closer to genera of the Inga alliance. There is also an Andean clade distinct from the remaining species of Abarema sensu lato, Hydrochorea, and Balizia.Conclusions. Two groups of Abarema sensu lato (one restricted to the Andes), ...