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

The genus <i>Preussia</i> 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, <i>P. jejuensis</i> sp. nov. and <i>P. koreensis</i> sp. nov., as well as one previously unrecorded species in Korea, <i>P. isomera</i>, from horse dung collected in Seopjikoji, Jeju Island, Republic of Korea. <i>P. jejuensis</i> sp. nov. is unique in producing conidia from conidiomata instead of teleomorphic structures, a feature not observed in any other known species of the <i>Preussia</i> genus. <i>P. koreensis</i> sp. nov. is morphologically distinguished by the absence of a neck, a smaller ascocarp diameter, smaller asci, and larger ascospores. In the phylogenetic analysis, <i>P. jejuensis</i> sp. nov. was closely related to <i>P. isomera</i> and <i>S. minimoides</i>, while <i>P. koreensis</i> sp. nov. was closely related to <i>P. arizonica</i>, <i>P. persica</i>, and <i>S. minima</i>. However, <i>P. jejuensis</i> sp. nov. and <i>P. koreensis</i> 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.