ABSTRACT
Karst caves are unique oligotrophic ecosystems characterised by the scarcity of organic litter, darkness, low to moderate temperatures, and high humidity, supporting diverse fungal communities. Despite their importance, little is known about the fungi in karst caves in Thailand. In 2019, we explored the culturable mycobiota associated with three selected types of substrates (air, soil/sediment and organic litter samples) from two karst caves, the Le Stegodon and Phu Pha Phet Caves, in the Satun UNESCO Global Geopark in southern Thailand. Based on morphological characters and multilocus phylogenetic analyses, eight new species (Actinomortierella caverna, Hypoxylon phuphaphetense, Leptobacillium latisporum, Malbranchea phuphaphetensis, Scedosporium satunense, Sesquicillium cavernum, Thelonectria satunensis and Umbelopsis satunensis) were described, illustrated, and compared to closely related species. These new fungal taxa form independent lineages distinct from other previously described species and classified into eight different families across six orders and two phyla (Ascomycota and Mucoromycota). This paper provides additional evidence that the karst caves located within the Satun UNESCO Global Geopark, situated in the southern region of Thailand, harbour a diverse range of newly discovered species. Citation: Preedanon S, Suetrong S, Srihom C, Somrithipol S, Kobmoo N, Saengkaewsuk S, Srikitikulchai P, Klaysuban A, Nuankaew S, Chuaseeharonnachai C, Chainuwong B, Muangsong C, Zhang ZF, Cai L, Boonyuen N (2023). Eight novel cave fungi in Thailand's Satun Geopark. Fungal Systematics and Evolution 12: 1-30. doi: 10.3114/fuse.2023.12.01.
ABSTRACT
Ophiocordyceps unilateralis sensu lato infects ants, modifies their behavior, and is found in many countries around the world. One unifying concept of all such parasitic associations is that both the parasite and the host adapt to maximize their fitness and reproductive output. However, little is known about the reproductive life span of this pathogen or about its alternation between asexual and sexual states, even though these two states affect host population dynamics differently. To address these issues, a permanent plot in a tropical rainforest was surveyed over the course of two years to examine the development of O. unilateralis s.l. and the incidence of infection of Polyrhachis and Camponotus ants, which were found to be specifically attacked by this fungus in Thailand. We document here for the first time the life cycle of this pathogen over the long term, which provides fundamental knowledge for the understanding of this fascinating host-parasite interaction.