TAXONOMY AND PHYLOGENY OF THE EUPHORBIACEAE TRIBE ERISMANTHEAE G.L.-WEBSTER (ERISMANTHUS, MOULTONIANTHUS, AND SYNDYOPHYLLUM)

The Erismantheae (monoecious, leaves opposite, stipules interpetiolar) contain three genera, Moultonianthus (monotypic), and Erismanthus and Syndyophyllum, each with 2 species. Moultonianthus is recognized by i ts persistent, large, cordate stipules; Erismanthus is characterized b y the catkin-like staminate inflorescences with very long-pedicelled f lowers; and characteristic for Syndyophllum are the inflorescences wit h both staminate flowers (in bundles) and pistillate flowers (one per bundle of staminate flowers). Both varieties of Syndyophyllum occident ale are now considered to be distinctive species, because an additiona l difference was found (one axillary bud of each leaf pair present hal fway along the petiole or not). The phylogenetic analysis of the Erism antheae, in comparison with two other tribes in the subfamily Acalypho ideae, the Chaetocarpeae and the Cheiloseae, shows that the Erismanthe ae are a very distinct, monophyletic group. Within the Erismantheae, E rismanthus and Syndyophyllum are closest related; all three genera are monophyletic.