Preface to the Special Issue on African Flora in a Changing World: Integrating multiple dimensions of diversity

Africa is home to globally important biodiversity.Straddling the equator and extending to temperate latitudes (at 37°N and 34°S; not including oceanic islands such as Marion and Prince Edward), the continent accommodates a variety of ecosystems and biomes, including tropical and temperate forests, savanna and montane grasslands, deserts, and Mediterranean-type ecosystems (Olson et al., 2011;Linder, 2014).The continent has remained relatively stable in the Cenozoic period (66 to 2.5 million years ago, Ma), despite dramatic geological events, including shifting coastlines, volcanism and formation of the rift valley (Couvreur et al., 2021).Africa has a rich diversity of vascular plants, with over 65 000 species recorded on the continent and its surrounding islands (Qian et al., 2021).This equates to approximately 18.5% of plant species recorded globally (Antonelli et al., 2023).However, efforts to catalogue African plant diversity and composition are uneven, with certain regions (e.g.tropical east and central Africa) being relatively well catalogued and others (e.g.Sudan) being barely explored (Marshal et al., 2016).At the same time, increased ecological and evolutionary research points to varied patterns of diversification and assembly of the flora; however, there is a lack of wider consolidation of the disparate knowledge.This Special Issue aims to bring together pan-African research and build a holistic synthesis of knowledge on the ecology and evolution of African plants.