Which extreme environments are inhabited by archaea?

Archaea are prokaryotic microorganisms that thrive in a diverse array of environments, including many once considered uninhabitable. While they are found in temperate and cold ecosystems, they are well-known for inhabiting extreme environments as extremophiles, such as:12

• High-Temperature Environments: Archaea inhabit hot springs and submarine hydrothermal vents. Some, such as Pyrolobus fumarii, can survive at temperatures as high as 113 °C (235 °F).1
• Acidic Environments: Certain species, including those in the genus Picrophilus and Thermoplasma, thrive in highly acidic conditions, such as acidic soils, volcanic steam vents (solfataras), and coal refuse sites, often growing at a pH near 0.13
• High-Salinity Environments: Halophilic archaea are adapted to thrive in environments with high salt concentrations.13
• Anaerobic Environments: Methanogenic archaea inhabit oxygen-free settings, including marshes, deep-sea marine sediments, and the digestive tracts of animals, including humans.13

Beyond these extreme habitats, archaea are ubiquitous in nature and play vital ecological roles in various global ecosystems.1