Heterotheca sect. Phyllotheca

Heterotheca sect. Phyllotheca (Nutt.) Harms includes all the prairie and montane goldenasters that were historically, but incorrectly, placed in Chrysopsis (Semple 1977, Semple et al. 1980, Semple 2006).  The ray and disc fruits are similar and the leaf and stem hairs are like those of H. sect. Heterotheca; the cells are osteolate with knobby surfaces.  Cronquist (1996) continued to include species of sect. Phyllotheca in his treatment of the goldenasters in the Flora of the Great Basin.  Molecular data subsequently supported the generic limits followed here rather than the traditional limits Cronquist accepted throughout his life (Brouillet et al. 2009).  Heterotheca sensu Semple grouped with Croptilon and Noticastrum in one clade, while Chrysopis grouped with Braduria in a second clade, and Pityopsis came out as a polytomy at the base of the Chrysopsidinae Clade.  Further work is needed.

Classification and illustrations