Unveiling hidden fungal diversity associated with coffee trees from China using a polyphasic approach and a global review of coffee saprobic fungi

Arabica coffee (Coffea arabica) is the most cultured and popular coffee bean in today’s world. Yunnan Province is well known as China's largest arabica coffee cultivation region. Fungi represent an important group of microorganisms associated with coffee, profoundly influencing its yield and quality. In this study, twelve fungal collections growing on dead and decaying twigs of coffee were collected and isolated to systematically document microfungi associated with coffee plants in Yunnan Province. Ten novel species, each representing a unique family within Pleosporales, were identified and introduced based on comprehensive morphological analyses and multigene phylogenetic studies. The ten new species belong to the families Bambusicolaceae, Didymellaceae, Didymosphaeriaceae, Longiostiolaceae, Lophiostomataceae, Massarinaceae, Neomassariaceae, Occultibambusaceae, Roussoellaceae, and Thyridariaceae with each family containing one new species. Macro- and micro-characteristics, descriptions, and phylogenetic trees indicating the placement of the new taxa are provided. In addition, pairwise homoplasy index (PHI) test results and morphological comparisons between the new species and closely related taxa are given. This study also establishes a comprehensive global inventory of saprobic fungi associated with coffee, which is intended to help researchers and professionals worldwide with practical information. This research enhances the understanding of coffee-associated fungal diversity in China and underscores the importance of introducing new saprobic fungal taxa related to coffee.