Taxonomy and systematics of micro-fungi associated with Coffea in southern China and northern Thailand

Yunnan, China, and Chiang Rai, Thailand, are located in the northern part of the Greater Mekong Subregion (GMS), characterized by its warm climate and rich ecological diversity, harboring an abundance of unique fungal resources. This comprehensive study investigated the saprobes associated with the economic crop coffee in Yunnan, China, and Chiang Rai, Thailand. A total of 360 collections were obtained from eight locations: Baoshan, Dali, Dehong, Jinghong, Lincang, Nujiang, and Pu'er in Yunnan in China and Chiang Rai in Thailand, and initial ITS analyses revealed that they belong to seven classes, 37 orders, 83 families, and 137 genera; the life modes of these genera are discussed based on prior studies. The fungal diversity and specificity of the above-mentioned eight collection places are also compared and discussed. Out of the 360 collections, 100 were selected for further morphological and multi-locus phylogenetic analyses based on well-preserved samples, abundant fruiting bodies, and fully matured morphological structures that can be used for morphological observation. The 100 collections belong to three classes, 23 orders, 51 families, and 64 genera. Halotthicoffea, Loculimurus, Neoamorocoelophoma, Occultineomassaria, Similroussoella, and Vaginomyces were identified as new genera. Forty-nine new species, one species with new sequence data, 40 new records, and four new collections are also reviewed. Acrocalymma daliense, Pseudohelminthosporium clematidis, Tubeufia coffeae, and Menisporopsis dinemasporioides are reported in their sexual and asexual morphs from different collection sites, and the taxonomic status of Pseudohelminthosporium clematidis is confirmed based on both morphological characteristics. In addition, two new combinations (Neoamorocoelophoma camelliae and Similroussoella jinghongensis) are introduced in this study based on evidence from morphology and multi-locus phylogeny. Detailed descriptions, illustrations, Scanning Electron Microscopy (SEM) images, and phylogenetic analyses results are provided for all the species.