Checklist of the arbuscular mycorrhizal fungi of Oaxaca, an important hotspot of biodiversity in Mexico

Background: Oaxaca, a southern State in Mexico, belongs to the Mesoamerican hotspot of biodiversity. The taxonomic and diversity knowledge of arbuscular mycorrhizal fungi (AMF) in Oaxaca State is scattered and accessibility to it is difficult. Questions: Which AMF species have been identified in Oaxaca and which is their distribution? Studied species: Arbuscular mycorrhizal fungi. Study site: State of Oaxaca, Mexico. Methods: We prepared an updated and annotated checklist of the AMF species with frequency of occurrence and the sampling sites where the species had been registered. All studies carried out previously (to date, 2022) were considered. Information on AMF taxa was available in scattered form in different publications in physical and electronic media, theses, projects, technical reports, and scientific papers. Results: The checklist includes 78 species, distributed among 23 genera, 10 families, and four orders. The most diverse families were Glomeraceae (26 species), followed by Gigasporaceae (20) and Acaulosporaceae (15), whereas the most diverse genera were Acaulospora and Glomus (15 and eight species, respectively). The most frequent species were Funneliformis geosporus, Acaulospora scrobiculata, and A. spinosa. The highest species diversity has been reported under the rhizosphere of Agave angustifolia, A. karwinskii, and Zea mays (39, 36, and 34 species, respectively). A new AMF species was recently isolated from the rhizosphere of a microendemic agave. Conclusions: The recorded AMF species of Oaxaca State confirms its position as one of the states with the highest AMF species diversity of Mexico.