Bayliss, JulianBittencourt‑Silva , Gabriela B.Branch, William R.Bruessow, CarlCollins , SteveCongdon , T. Colin E.Conradie , WernerCurran , MichaelDaniels, Savel R.Darbyshire , IainFarooq , HarithFishpool , LincolnGrantham, GeoffreyMagombo , ZachariaMatimele , HermenegildoMonadjem, AraMonteiro, JoseOsborne , JoSaunders , JustinSmith , PaulSpottiswoode , Claire N.Taylor, Peter J.Timberlake , JonathanTolley , Krystal A.Tovela , EricaPlatts, Philip J.2025-07-022025-07-022024-03-12Bayliss, J., Bittencourt‑Silva, G.-B., Branch, W.R. et al. 2024, 'A biogeographical appraisal of the threatened South East Africa Montane Archipelago ecoregion', Scientific Reports, vol. 14, no., 5971, pp. 1-16. https://doi.org/10.1038/s41598-024-54671-z.2045-232210.1038/s41598-024-54671-zhttp://hdl.handle.net/2263/103116DATA AVAILABILITY : The raw data used in this study are provided in the supplementary materials, including endemic species data and site listings (Table SI1), a table of estimated divergence dates (Table SI2), and spatial data files for the delineation of core sites and convex hull (available at https:// doi.org/10.6084/ m9.figshare.24586941).Recent biological surveys of ancient inselbergs in southern Malawi and northern Mozambique have led to the discovery and description of many species new to science, and overlapping centres of endemism across multiple taxa. Combining these endemic taxa with data on geology and climate, we propose the ‘South East Africa Montane Archipelago’ (SEAMA) as a distinct ecoregion of global biological importance. The ecoregion encompasses 30 granitic inselbergs reaching > 1000 m above sea level, hosting the largest (Mt Mabu) and smallest (Mt Lico) mid-elevation rainforests in southern Africa, as well as biologically unique montane grasslands. Endemic taxa include 127 plants, 45 vertebrates (amphibians, reptiles, birds, mammals) and 45 invertebrate species (butterflies, freshwater crabs), and two endemic genera of plants and reptiles. Existing dated phylogenies of endemic animal lineages suggests this endemism arose from divergence events coinciding with repeated isolation of these mountains from the pan-African forests, together with the mountains’ great age and relative climatic stability. Since 2000, the SEAMA has lost 18% of its primary humid forest cover (up to 43% in some sites)—one of the highest deforestation rates in Africa. Urgently rectifying this situation, while addressing the resource needs of local communities, is a global priority for biodiversity conservation.en© The Author(s) 2024. This article is licensed under a Creative Commons Attribution 4.0 International License.EndemismClimateSouth East Africa Montane Archipelago’ (SEAMA)InselbergsArticle