Saprobic Melomastia taxa from Bauhinia variegata and Litchi chinensis: a new species and a new host record from southern China

Abstract

During investigations of saprobic microfungi associated with the litter of Bauhinia variegata and Litchi chinensis in Guangdong and Guangxi provinces, southern China, four fungal strains were isolated. Based on combined phylogenetic analyses of LSU, SSU, ITS, and tef1-α gene regions, morphological comparisons, and a Pairwise Homoplasy Index (PHI) test, we describe a new species, Melomastia bauhiniae from B. variegata, and a new host record for Melomastia winteri from L. chinensis. Morphologically, M. bauhiniae differs from other species in the genus in having semi-immersed, globose to subglobose, carbonaceous perithecia, a thin peridium, cylindrical asci, and fusiform and hyaline ascospores. Phylogenetic analyses indicate that the new taxon forms a distinct lineage within Melomastia, and the PHI test showed no significant recombination, supporting its recognition as an independent species. For all novel identifications, detailed morphological descriptions, photographic documentation, phylogenetic analyses, and PHI test results are provided. These findings expand the host range and geographic distribution of Melomastia, contribute to the understanding of saprobic fungi associated with Bauhinia variegata and Litchi chinensis, and expand the known fungal diversity of southern China.