Astrobiology in a mesophilic tropical country: A database and a review of analog environments in Brazil.

Astrobiological analog environments comprise Earth-based environments that share similarities with a target setting (another planetary body or Precambrian Earth conditions) and whose defining features influence extant or fossil biological components, enabling astrobiological interpretation. Although not synonymous with extreme environments, they often impose selective pressures that favor extremophiles and extremotolerant organisms, making them suitable for exploring habitability, the limits of life, and its evolutionary history. Global cataloging initiatives have identified such sites worldwide; however, Brazil is often absent despite its growing research effort in astrobiology. Here, we developed a comprehensive database compiling Brazilian environments proposed as astrobiological analogs. Publications in English and Portuguese up to 2025 were reviewed using keywords such as "extremophile*", "brazil", and "analog*". Selected studies either explicitly described analog environments or investigated extremophiles and their habitats in Brazil. Each query included environment type, microenvironment, abiotic factors, putative extraterrestrial analog, life forms, terrestrial biome, conservation status, research area, and astrobiological recognition. Our analysis revealed a wide diversity of analog environments across terrestrial, subterranean, and aquatic settings. We argue that Brazil, despite being traditionally considered "mesophilic", harbors a valuable array of astrobiologically relevant analog sites, reinforcing the need to expand global analog studies beyond traditionally recognized regions.