During the investigation of lignicolous freshwater fungi in the Tibetan Plateau habitat, fifteen collections were isolated from submerged decaying wood. Fungal characteristics are commonly found as punctiform or powdery colonies with dark pigmented and muriform conidia. Multigene phylogenetic analyses of combined ITS, LSU, SSU and TEF DNA sequences showed that they belong to three families in Pleosporales. Among them, Paramonodictys dispersa, Pleopunctum megalosporum, Pl. multicellularum and Pl. rotundatum are established as new species. Paradictyoarthrinium hydei, Pleopunctum ellipsoideum and Pl. pseudoellipsoideum are reported as new records on the freshwater habitats in Tibetan Plateau, China. The morphological descriptions and illustrations of the new collections are provided.

Tubeufiaceae, a cosmopolitan family with a worldwide distribution, is mostly reported as saprobic on decaying woody materials from both aquatic and terrestrial habitats. The family is commonly found as helicosporous hyphomycetes, while some are chlamydosporous and phragmosporous. In this study, thirteen helicosporous hyphomycetes were collected from Thailand and China. The phylogenetic analyses of combined ITS, LSU, TEF1-α, and RPB2 sequence data placed them in Dematiohelicomyces, Helicoma, Helicotruncatum, Neohelicosporium, Parahelicomyces, and Tubeufia within Tubeufiaceae. Three new species, Tubeufia cocois, Parahelicomyces chiangmaiensis, and Neohelicosporium bambusicola, one new host record, Tubeufia laxispora, and one new geographic record, T. longihelicospora, are introduced based on both morphological characteristics and phylogenetic analyses. In addition, Dematiohelicomyces helicosporus, Helicoma guttulatum, Helicotruncatum palmigenum, and Tubeufia cylindrothecia are described with detailed descriptions and color photo plates.

Tetraplosphaeriaceae (Pleosporales, Ascomycota) is a family with many saprobes recorded from various hosts, especially bamboo and grasses. During a taxonomic investigation of microfungi in tropical and subtropical forest regions of Guizhou, Hainan and Yunnan provinces, China, several plant samples were collected and examined for fungi. Four newly discovered species are described based on morphology and evolutionary relationships with their allies inferred from phylogenetic analyses derived from a combined dataset of LSU, ITS, SSU, and tub2 DNA sequence data. Detailed illustrations, descriptions and taxonomic notes are provided for each species. The four new species of Tetraplosphaeriaceae reported herein are Polyplosphaeria guizhouensis, Polyplosphaeria hainanensis, Pseudotetraploa yunnanensis, and Tetraploa hainanensis. A checklist of Tetraplosphaeriaceae species with available details on their ecology is also provided.

During a survey of microfungi associated with forest plants, four specimens related to Kirschsteiniothelia were collected from decaying wood in Guizhou, Hainan and Yunnan Provinces, China. Kirschsteiniothelia species have sexual and asexual forms. They are commonly found as saprophytes on decaying wood and have been reported as disease-causing pathogens in humans as well. In this study, we introduce three novel Kirschsteiniothelia species (K. bulbosapicalis, K. dendryphioides and K. longirostrata) and describe a new host record for K. atra, based on morphology and multi-gene phylogenetic analyses of a concatenated ITS, LSU and SSU rDNA sequence data. These taxa produced a dendryphiopsis- or sporidesmium-like asexual morph and detailed descriptions and micromorphological illustrations are provided. Furthermore, we provide a checklist for the accepted Kirschsteiniothelia species, including detailed host information, habitat preferences, molecular data, existing morphological type, country of origin and corresponding references.

Phaeoisaria is widely distributed in the Northern Hemisphere and characterized by straight or flexuous, erect, dark brown to black synnemata with parallelly adpressed conidiophores and ellipsoidal to obovoid, solitary, hyaline, aseptate, acrogenous conidia. This study’s phylogenetic analyses of combined ITS, LSU, and SSU sequence data showed that the eight Xizang Phaeoisaria strains represent at least three phylogenetic species. A new species Phaeoisaria motuoensis, and two new geographical records of P. clematidis and P. sedimenticola from Xizang, China are reported. The taxa are introduced here with descriptions, color photographs, and phylogenetic analyses results and are compared with similar species.

During an investigation of lignicolous freshwater fungi in the Tibetan Plateau, three Aquapteridospora taxa were collected from freshwater habitats in Xizang, China. The new species possess polyblastic, sympodial, denticles conidiogenous cells and fusiform, septate, with or without sheath conidial, that fit within the generic concept of Aquapteridospora, and multi-gene phylogeny placed these species within Aquapteridospora. Detailed morphological observations clearly demarcate three of these from extant species and are hence described as new taxa. The multi-gene phylogeny of the combined LSU, TEF1-α, and ITS sequence data to infer phylogenetic relationships and discuss phylogenetic affinities with morphologically similar species. Based on morphological characteristics and phylogenetic analyses, three new species viz. A. linzhiensis, A. yadongensis, and A. submersa are introduced. Details of asexual morphs are described, and justifications for establishing these new species are also provided in this study.