Heterosamarasect.Villosospermacomb. nov. (Polygalaceae) from eastern Asia

In this study, three species of Polygala L. (Polygalaceae) are transferred to the genus Heterosamara Kuntze based on plant morphology, habitat, and palynological features. Heterosamara wattersii (Hance) Paiva & P. Silveira comb. nov., H. caudata (Rehder & E. H. Wilson) Paiva & P. Silveira comb. nov. and H. resinosa (S. K. Chen) Paiva & P. Silveira comb. nov. from tropical and sub-tropical forests of eastern Asia are described. The first two are also illustrated and described palynologically. The inclusion of these species within this genus is justified by their typical heteropolar pollen with bilateral symmetry, bilobate crest (appendage in the keel), large lanceolate leaves with petioles, and forest habitats. The lack of information on the flower morphology of H. resinosa makes the classification of this species more difficult, as it is only known from the type specimen. Nonetheless, the habit, habitat and seed morphology place it in the same taxonomic group as the other species studied. The seeds of these three species present very distinctive features within the genus Heterosamara placing them in a newly recognized section, Heterosamara sect. Villososperma (C. Y. Wu & S. K. Chen) Paiva & P. Silveira comb. nov. Identification keys are provided for the genera, sections and species studied.