Unravelling the hidden diversity of cave mycobiota in Thailand抯 Satun Geopark

Abstract

Karst caves are distinctive ecosystems that have limited nutrients darkness low to moderate temperatures and high moisture levels which allow for a diverse range of fungal communities to thrive. Despite their significance little is understood about the fungi found in karst caves in Thailand. In 2019 we studied the cultured mycobiota from five substrate types (air water rock soil/sediment and organic debris) in two karst caves (Le Stegodon and Phu Pha Phet Caves) of the Satun UNESCO Global Geopark southern Thailand. A cumulative count of 829 distinct fungal morphological types was identified encompassing 319 fungal culturable were observed. Based on preliminary analyses of the internal transcribed spacer (ITS) sequence using BLAST searches the most common phylum among the fungal morphotypes was Ascomycota harboring 282 species in 91 genera 93.4% of which were distributed in the classes Eurotiomycetes Sordariomycetes and Dothideomycetes. The most common fungal genera identified in the two karst caves were Aspergillus Penicillium Cladosporium Talaromyces Xylaria and Trichoderma with 45 41 24 14 14 and 6 species identified respectively. Discovering fungi in Thai karst caves highlights the extensive fungal diversity in the Satun UNESCO Global Geopark implying undiscovered species and emphasizing the need for comprehensive investigations in other unexplored Thai karst caves. ? 2023 The Author(s).