Most genera of the HHE clade are grouped in two major sister clades. One of the two clades contains the core Heliantheae genera and in turn has two major clades. Each of the two core Heliantheae clades has as its basalmost lineage a white ligulate genus. The monotypic genus Rojasianthe and Montanoa share white ligules, acrescent pales after anthesis, and a chromosome number of x = 19. Rojasianthe is basal to the lineage containing the Verbesininae s. str., the Engelmanniinae sister to the Rudbeckiinae, and this sister to a terminal clade containing selected members of the Ambrosiinae, Helianthinae, Zaluzaniinae, Zinniinae, the conical receptacle genera of the Ecliptinae (exemplified by the genus Acmella), and the epaleate genus Trichocoryne. The genus Parthenium is sister to Dugesia; both genera share a similar achene dispersal mechanism and floral sexuality pattern. The genus Ambrosia in some of the trees is sister to Encelia and basal to most genera of this clade. Encelia is not the immediate sister taxon of the Helianthinae. The other clade of core Heliantheae has the genus Montanoa as its basalmost lineage sister to the core Ecliptinae. The major clade sister to core Heliantheae contains a disparate group of taxa ranging from traditionally helianthoid paleate taxa such as those classified under subtribes Galinsoginae, Melampodiinae, Milleriinae, and Guardiolinae, along with epaleate taxa such as Galeana/Villanova, the Peritylinae, and the Madiinae. Support for deeper clades of the major group of paleate and epaleate taxa that includes Eupatorieae is weak, but the component taxa are probably closely related based on strong support for other deep clades of the HHE tree. The results outlined here provide support for changes in the classification of tribes Helenieae and Heliantheae. A tentative classification scheme for the HHE clade will be presented.

Key words: Asteraceae. Helenieae, chloroplast DNA, Eupatorieae, Heliantheae, phylogenetics