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.

Asexual morphs of freshwater fungi have been mostly reported from tropical and subtropical regions. From our ongoing investigation of the diversity and taxonomy of freshwater microfungi in Thailand, a country with rich natural resources and diverse ecosystems, Parafuscosporella ellipsoconidiogena sp. nov. and P. obovata sp. nov., collected from decaying submerged twigs at Phalad Waterfall in a conserved forest in Chiang Mai Zoo, Chiang Mai Province, northern Thailand, are proposed. DNA phylogenies based on a combination of ITS and LSU datasets support the placement of these species in Parafuscosporella (Fuscosporellaceae, Fuscosporellales, Sordariomycetes), and these two novel species differ from known species in terms of morphology. Detailed descriptions, illustrations and a key to Parafuscosporella species are provided, as well as comparisons with other accepted Parafuscosporella species.

Species of Kionochaeta are saprobes commonly associated with decaying plant materials. As a part of surveys on freshwater microfungi, Kionochaeta-like taxon was found on a submerged decaying twig at a rivulet in the protected forest area of Khao Kheow Open Zoo (KKOZ), eastern Thailand. This taxon is microscopically similar to Kionochaeta, but clearly differs by its accessory lateral setiform branches and sterile setae arising beside the conidiophores. Multi-locus phylogenies inferred from four combined loci (SSU, ITS, LSU and RPB2) demonstrated that this taxon clustered as a unique clade with Kionochaeta species (Chaetosphaeriaceae, Chaetosphaeriales). Therefore, we introduce this taxon as K. setosimplicia, and it is phylogenetically close to K. castaneae, K. ramifera and K. pughii. Kionochaeta setosimplicia is separated from K. microspora and K. spissa. In Kionochaeta clade 1, K. nanophora forms a basal taxon. Kionochaeta ivoriensis forms a distinct Kionochaeta clade 2 distant from other Kionochaeta.