Brazil is a megadiverse country, with around 20 % of all known biodiversity in the world. This diversity is distributed in six major biomes that present different floristic characteristics. These environments suffer constant threats, and the knowledge about their communities is essential for conservation. Among the soil organisms, the arbuscular mycorrhizal fungi (AMF – Glomeromycota) play a fundamental role in maintaining plant communities and are distributed in manifold environments, symbiotically associated to most terrestrial plants. The present synthesis brings the Brazilian records of 192 AMF species, belonging to 38 genera and 15 families, which represents circa 60 % of all diversity known in Glomeromycota. Most of the records of AMF species are in the Atlantic rainforest (153 species), Cerrado savanna (140), Caatinga dry forest (120) and the Amazon rainforest (97 species). Pantanal and Pampa so far have 19 and five AMF species, respectively. In general, Brazilian biomes harbor high AMF species richness, constituting an important repository of Glomeromycota taxa. The conservation of these areas is necessary to ensure the permanence of the native plant communities and associated fungi. Likewise, the importance of AMF diversity studies has to be emphasized, considering that these microorganisms are essential elements for the conservation of terrestrial environments and the survival of many threatened plant species.
