Format: ORAL

Nicola G. Bergh1,5, Zaynab Shaik2,4, Thaabiet Parker1,3, Lauren M. C. James3, Allan G. Ellis2, Robert Sadler3, Bengt Oxelman4, G. Anthony Verboom3,4

1 The Compton Herbarium, South African National Biodiversity Institute, Kirstenbosch, Cape Town, South Africa 2 Department of Botany and Zoology, University of Stellenbosch, Stellenbosch, South Africa 3 Department of Biology, University of Cape Town, Rondebosch, Cape Town, South Africa 4 Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden 5 Gothenburg Botanical Garden, Gothenburg, Sweden.

The Cape Flora has very high concentrations of species diversity and extremely high levels of endemism in a relatively small geographic area. As for most temperate regional floras, Compositae is the most species-rich family. A number of endemic composite lineages have radiated within (and in many cases, subsequently dispersed out of) the region, after adaptation to the unique edaphic and climatic conditions that characterise the island-like Cape habitats. Most of the taxonomic work on Cape Compositae occurred more than thirty years ago, before the advent of modern methods and resources, and there has been very little evolutionary work on these systems. Here, I present advances in species discovery and in the understanding of speciation processes in the Cape Flora, based largely on our research in two Cape-centred tribes, the Gnaphalieae (everlasting daisies) and the Calenduleae (the African marigolds). These studies make use of herbarium specimens, online databases, and citizen-science platforms; extensive fieldwork; and a range of morphological and molecular techniques, including genomic data, to reconstruct evolutionary relationships, discover new species, and examine the context of diversification.  We extrapolate from these results to explore possible implications for future species discovery in other members of the Compositae of this hyperdiverse region.