show Abstracthide AbstractThe hyperarid core of the Atacama Desert is an extremely harsh environment previously thought to be colonized by only a few heterotrophic bacterial species. Here we sampled soils below and beside the boulders of the Atacama hyperarid core to characterize the differences in microbial community and their metabolic potentials between the two sample types. Notably, a novel genus of Thaumarchaeota adapted to hyperaridity was detected in abundance below the boulders of the Atacama Desert. In-depth genomic characterization of these genomes elucidated their niche potential roles in N and C cycling in highly nutrient deficient Atacama Desert soils, as well as key adaptations against oxidative stress, salt stress and hyperaridity.vThe results reveal the remarkable adaptability and resilience of Thaumarchaeota, expanding the physical limits of thaumarchaeal habitat range to include hyperarid, high salt and extremely low-carbon environments.