Preussia jejuensis sp. nov., P. koreensis sp. nov., and P. isomera, Coprophilous Fungi Isolated from Horse Dung in Seopjikoji, Jeju Island in the Republic of Korea.

The genus Preussia is widely distributed and includes species with ecological and biotechnological importance. In this study, morphological and phylogenetic analyses of the ITS and LSU rDNA sequences revealed two novel species, P. jejuensis sp. nov. and P. koreensis sp. nov., as well as one previously unrecorded species in Korea, P. isomera, from horse dung collected in Seopjikoji, Jeju Island, Republic of Korea. P. jejuensis sp. nov. is unique in producing conidia from conidiomata instead of teleomorphic structures, a feature not observed in any other known species of the Preussia genus. P. koreensis sp. nov. is morphologically distinguished by the absence of a neck, a smaller ascocarp diameter, smaller asci, and larger ascospores. In the phylogenetic analysis, P. jejuensis sp. nov. was closely related to P. isomera and S. minimoides, while P. koreensis sp. nov. was closely related to P. arizonica, P. persica, and S. minima. However, P. jejuensis sp. nov. and P. koreensis sp. nov. were clearly distinguished from their related species. This study expands the understanding of the biodiversity of coprophilous fungi and its distribution in Jeju Island, a region where horse breeding has been practiced for centuries, emphasizing the ecological importance of dung as a fungal habitat.