Karst caves are oligotrophic environments that appear to support a high diversity of fungi. Studies of fungi in Thailand's caves are limited. During a 2019 exploration of the mycobiota associated with soil samples from a karst cave, namely, Phu Pha Phet in the Satun UNESCO Global Geopark in Satun Province, southern Thailand, two previously undescribed fungi belonging to Talaromyces (Trichocomaceae, Eurotiales, Eurotiomycetes) were studied using a polyphasic approach combining phenotypic and molecular data. Based on datasets of four loci (ITS, BenA, CaM, and RPB2), phylogenetic trees of the section Trachyspermi were constructed, and two new species-Talaromyces phuphaphetensis sp. nov. and T. satunensis sp. nov.-phylogenetically related to T. subericola, T. resinae, and T. brasiliensis, are described. Detailed descriptions and illustrations of the new species are provided. This study increases the number of cave-dwelling soil fungi discovered in Thailand's Satun UNESCO Global Geopark, which appears to be a unique environment with a high potential for discovering fungal species previously undescribed.
Keywords: Phu Pha Phet karst cave; Trichocomaceae; cave-dwelling soil micro-fungi; polyphasic taxonomy; section Trachyspermi.