Progress towards a monophyletic <i>Ozothamnus</i> (Asteraceae: Gnaphalieae)

Abstract The Cassinia clade (Asteraceae: Gnaphalieae) is a predominantly shrubby group of ca. 100 species occurring in Australia and New Zealand. Most species are currently placed in the large genera Cassinia and Ozothamnus , and their various satellite genera comprise between one and five species each. Delimitation of genera in the clade has generally been justified by few or single characters like absence or presence of the pappus or paleae (receptacle bracts). A previous phylogenetic analysis of the clade using Sanger sequence data confirmed Ozothamnus to be non‐monophyletic with various genera including Cassinia nested inside it, but nuclear and chloroplast data showed incongruence and limited branch support. Here, we present a phylogenetic analysis of nearly all species in the Cassinia clade inferred from hundreds of protein‐coding genes recovered using target capture and next‐generation sequencing. Our results confirm the non‐monophyly of Ozothamnus and resolve seven clades with high confidence. To progress towards a natural classification of the Cassinia clade, we transfer two clades comprised entirely of species of Ozothamnus to Cassinia , return Ozothamnus pholidotus to Haeckeria , and transfer both species of Odixia to Ozothamnus . Delimitation of the small genera other than Haeckeria , however, requires further study, as they are distributed across two morphologically and ecologically heterogeneous clades. Lectotypes are chosen for the following names: Helichrysum diotophyllum F.Muell., Ozothamnus beckleri F.Muell., and Ozothamnus lepidophyllus Steetz. Second‐step lectotypes are selected for Ozothamnus adnatus DC. and Helichrysum cassinioides Benth.