Hotspot getting hotter: Increased knowledge on tetrapod endemism, habitat loss and the plight of the most threatened savanna in the world

The Cerrado is the second-largest Neotropical ecoregion and the richest and most threatened savanna globally. It is recognized as a biodiversity hotspot due to its high number of endemic species and significant rates of habitat loss. Here, we synthesise recent advances in taxonomic and biogeographic knowledge of endemic terrestrial vertebrates (tetrapods) in the Cerrado, with an update on current levels of threat, habitat loss and protection for these endemic biotas. Over the past two decades, new tetrapods have been described throughout the Cerrado at an average rate of six species per year, with recently discovered species exhibiting restricted ranges. Most new species were described from regions already highly impacted by human activities, and almost half of all endemic tetrapod species showed <50 % of their range covered by natural habitats. Moreover, >87 % of species have <17 % of their ranges within protected areas, indicating substantial protection gaps in the Cerrado. Our findings suggest that the number of threatened species in the Cerrado is likely underestimated, with many data-deficient species impacted by recent habitat loss and lacking adequate protection. Previous assessments of Cerrado biodiversity have underestimated endemism levels, and the newly discovered endemic tetrapods are poorly represented in red lists and conservation actions. Urgent conservation measures are needed to prevent biodiversity loss in this highly endemic and most threatened savanna in the world.