Global Centers of Vascular Plant Diversity

The diversity of vascular plants is very unevenly distributed across the globe. The five centres that reach species richness of more than 5,000 spp./10,000 km 2 (Costa Rica-Choco, Atlantic Brazil, Tropical Eastern Andes, Northern Borneo, New Guinea) cover only 0.2 % of the terrestrial surface. On the other hand approximately 18,500 spp. are endemic to these centres which represent 6.2 % of all vascular plant species. A world map of vascular plant richness is presented based on an extensively expanded data base (more than 3,300 species richness figures for different regions of the world) and a refined methodology. Most of the global centres are located in mountainous regions within the humid tropics, where suitable climatic conditions and high levels of geodiversity, i.e., the diversity of abiotic conditions, coincide. A complete review of most prominent climatic, geologic, and floristic features of the 20 centres of phytodiversity with more than 3,000 spp. / 10,000 km 2 is presented.