Vanishing ecosystems: The looming threat of climate change on an iconic genus Vellozia in the Brazilian campos rupestres

Climate change poses a significant threat to biodiversity and habitats worldwide, with mountainous regions and endemic species particularly vulnerable. One such ecosystem is the campos rupestres, a mountainous environment in the highlands of central-eastern Brazil, characterized by high species richness and endemism. Among this ecosystem's most diverse and abundant endemic genera is Vellozia (Velloziaceae), comprising 127 species. Using species distribution modeling, we assessed how climate change will likely affect suitable habitats for the genus. Additionally, we conducted IUCN extinction risk assessments and applied the EDGE2 method, incorporating a phylogenetic framework to identify species that should be prioritized for conservation. Our findings indicate that, on average, each species of Vellozia is expected to lose 84.26 % of its suitable habitat by 2060, with 13 species projected to lose 100 % of their habitat. Over half of the genus is projected to lose over 92 % of its suitable habitat. The species richness and endemism of Vellozia in the campos rupestres will diminish substantially in both geographic extent and species count. This decline is particularly concerning given that nearly half of the genus is microendemic, with 16 species occurring entirely outside protected areas. These findings highlight the potential for climate change to drastically reduce the habitat size and species richness of Vellozia and overall biodiversity within the campos rupestres ecosystem.