A revised phylogenetic classification of tribe Phyllantheae (Phyllanthaceae)

Abstract

<p>The majority of tribe Phyllantheae (Phyllanthaceae) is currently placed in the paraphyletic genus <i>Phyllanthus</i> and discussions have persisted on how to resolve this issue. Here, we split <i>Phyllanthus</i> into ten monophyletic genera, which are all reinstatements of former genera, but with changes made to the circumscription and constituent species of each group. The genera Breynia, Glochidion and Synostemon were recently found to be nested within <i>Phyllanthus</i> and discussions ensued whether or not to subsume everything into <i>Phyllanthus</i> s.l. Instead of combining all these genera, we here implement the solution of splitting <i>Phyllanthus</i> into strictly monophyletic genera to ensure that the classification is consistent with the latest phylogenetic results. The new classification is based on a phylogenetic framework combined with differences in habit, branching type, floral, fruit and pollen morphology. With this new division of the genus <i>Phyllanthus</i>, tribe Phyllantheae will consist of the following 18 genera: <i>Breynia</i>, <i>Cathetus</i>, <i>Cicca</i>, <i>Dendrophyllanthus</i>, <i>Emblica</i>, <i>Flueggea</i>, <i>Glochidion</i>, <i>Heterosavia</i>, <i>Kirganelia</i>, <i>Lingelsheimia</i>, <i>Lysiandra</i>, <i>Margaritaria</i>, <i>Moeroris</i>, <i>Nellica</i>, <i>Nymphanthus</i>, <i>Phyllanthus</i>, <i>Plagiocladus</i> and <i>Synostemon</i>. As a result of the reinstated genera, five new names for illegitimate combinations or previous overlooked nomenclatural anomalies and 645 new combinations are proposed. Several keys are provided to distinguish the reinstated genera. Full species lists are given for the reinstated genera treated here except for <i>Breynia</i>, <i>Synostemon</i> and <i>Glochidion</i>.</p>