Format: ORAL

Božo Frajman

Department of Botany, University of Innsbruck, Innsbruck, Austria

Euphorbia subgenus Esula is the earliest diverging lineage within Euphorbia and with roughly 480 species represents the most significant radiation of the genus in temperate areas of the Old World, with highest diversity in the Mediterranean and Irano-Turanian regions. The overall infrageneric structure has been largely resolved using plastid and nuclear ITS sequences, leading to recognition of 21 sections. In contrast, spatio-temporal diversification within the sections and partly also the relationships among them remain poorly understood. I will present the outcomes of ongoing studies on the diversification of different species groups within Euphorbia sect. Esula based on an integrative approach using phylogenetic and phylogenomic data, relative genome size and chromosome number estimations, as well as morphometric and ecological analyses. They are all important for inferring inter-specific boundaries and establishing a stable taxonomy within the subgenus. I will address the significance of polyploidisation for diversification within the subgenus and summarise major open questions to stimulate further research on this fascinating group of flowering plants.