(Vol. 08, 2005-12) Taxonomy of Hymenoxys Subgenus Rydbergia (Asteraceae: Helenieae: Tetraneurinae)

Hymenoxys subg. Rydbergia comprises H. brandegeei, H. grandiflora, and H. insignis. The treatment includes a discussion of the original circumscription of the taxa, the description of the genus Rydbergia to accommodate H. brandegeei and H. grandiflora, the eventual placement of Rydbergia within Hymenoxys as a subgenus, and relationships of the three taxa to one another and to other taxa of Hymenoxys. The treatment also includes synonymies, descriptions, and range maps for each of the species, and lectotypification of Actinella brandegeei.