Lichens are symbiotic organisms found on various substrates, including rocks, the soil surface, and on trees. Most lichens acquire most of their nutrients from rainwater and atmospheric deposition; many of them also accumulate atmospheric pollutants and are useful environmental bioindicators. This study presents a timely update of lichen diversity in the Amazon and Cerrado biomes. 150 articles were examined from recent years (2013–2023), from PubMed, Web of Science, Scielo, Scopus, Capes Journals, National Digital Libraries and other academic sources. After applying non-inclusion criteria, 36 studies were selected for closer analysis. The publications revealed a rich diversity of lichens, with a total of 58 families, 241 genera, and 1554 species identified from the two biomes. Notably, 33 families, 96 genera and 293 species were reported from both the Amazon and the Cerrado. The most species-rich families were Graphidaceae, Trypetheliaceae, Parmeliaceae, Arthoniaceae, and Pilocarpaceae, with the most prominent genera being Astrothelium, Glyphis, Pyrenula, Porina, Ocellularia, and Heterodermia. The Amazon had more taxa in all taxonomic categories. The lichens of Brazilian both biomes play significant, but still largely unexplored roles in environmental maintenance. The requirements of most species are almost unknown, with major knowledge gaps also in distribution patterns and habitat ecology. However, many lichens in both regions presumably face significant threats from deforestation, wildfires, mining, and urban sprawl. This emphasizes the need for effective measures to protect and preserve lichens as an integral part of environmental management and the preservation of Brazilian biomes.
