Pleomorphic Dematiomelanommayunnanense gen. et sp. nov. (Ascomycota, Melanommataceae) from grassland vegetation in Yunnan, China

During a survey of microfungi associated with grasslands and related vegetation types from Yunnan Province in China, various ascomycetous and coelomycetous fungi were isolated. This study reports the discovery of four strains of ascomycetous and coelomycetous fungi from dead stalks of Hypericummonogynum L. (Hypericaceae) and Rubusparvifolius L. (Rosaceae) in the Zhaotong region of Yunnan Province, China. The isolates were characterized using multi-locus phylogenetic analyses and were found to represent a new monophyletic lineage in Melanommataceae (Pleosporales, Dothideomycetes). This new clade was named as Dematiomelanommayunnanense gen. et sp. nov. which consists of both sexual and asexual morphs. The sexual morph is characterized by globose to subglobose ascomata with a central ostiole, cylindrical asci with a pedicel and ocular chamber, and muriform, ellipsoidal to fusiform ascospores. The asexual morph has synanamorphs including both brown, muriform macroconidia and hyaline, round to oblong or ellipsoidal microconidia. These findings contribute to the understanding of fungal diversity in grasslands and related vegetation types in Yunnan Province, China.

Integrative Taxonomy of Novel Diaporthe Species Associated with Medicinal Plants in Thailand

During our investigations of the microfungi on medicinal plants in Thailand, five isolates of Diaporthe were obtained. These isolates were identified and described using a multiproxy approach, viz. morphology, cultural characteristics, host association, the multiloci phylogeny of ITS, tef1-α, tub2, cal, and his3, and DNA comparisons. Five new species, Diaporthe afzeliae, D. bombacis, D. careyae, D. globoostiolata, and D. samaneae, are introduced as saprobes from the plant hosts, viz. Afzelia xylocarpa, Bombax ceiba, Careya sphaerica, a member of Fagaceae, and Samanea saman. Interestingly, this is the first report of Diaporthe species on these plants, except on the Fagaceae member. The morphological comparison, updated molecular phylogeny, and pairwise homoplasy index (PHI) analysis strongly support the establishment of novel species. Our phylogeny also revealed the close relationship between D. zhaoqingensis and D. chiangmaiensis; however, the evidence from the PHI test and DNA comparison indicated that they are distinct species. These findings improve the existing knowledge of taxonomy and host diversity of Diaporthe species as well as highlight the untapped potential of these medicinal plants for searching for new fungi.

Insight into the Systematics of Microfungi Colonizing Dead Woody Twigs of Dodonaea viscosa in Honghe (China)

Members of Dodonaea are broadly distributed across subtropical and tropical areas of southwest and southern China. This host provides multiple substrates that can be richly colonized by numerous undescribed fungal species. There is a severe lack of microfungal studies on Dodonaea in China, and consequently, the diversity, phylogeny and taxonomy of these microorganisms are all largely unknown. This paper presents two new genera and four new species in three orders of Dothideomycetes gathered from dead twigs of Dodonaea viscosa in Honghe, China. All new collections were made within a selected area in Honghe from a single Dodonaea sp. This suggests high fungal diversity in the region and the existence of numerous species awaiting discovery. Multiple gene sequences (non-translated loci and protein-coding regions) were analysed with maximum likelihood and Bayesian analyses. Results from the phylogenetic analyses supported placing Haniomyces dodonaeae gen. et sp. in the Teratosphaeriaceae family. Analysis of Rhytidhysteron sequences resulted in Rhytidhysteron hongheense sp. nov., while analysed Lophiostomataceae sequences revealed Lophiomurispora hongheensis gen. et sp. nov. Finally, phylogeny based on a combined dataset of pyrenochaeta-like sequences demonstrates strong statistical support for placing Quixadomyceshongheensis sp. nov. in Parapyrenochaetaceae. Morphological and updated phylogenetic circumscriptions of the new discoveries are also discussed.

Bipolaris marantae sp. nov., A Novel Helminthosporoid Species Causing Foliage Blight of the Garden Plant Maranta leuconeura in Brazil

A severe leaf spot, turning to foliage blight, was observed on leaves of Maranta leuconeura growing in a garden in Brazil (state of Rio de Janeiro) in 2015. A dematiaceous hyphomycete bearing a morphology typical of a helminthosporoid fungi was regularly found in association with diseased tissues. The fungus was isolated and pathogenicity was demonstrated through the completion of Koch's postulates. A morphology and molecular analysis led to the conclusion that the fungus belonged to the genus Bipolaris, which is characterized by having fusiform conidia, externally thickened and truncate hila and a bipolar pattern of germination. Additionally, homology of internal transcribed spacer and GAPDH sequences with sequences of other Bipolaris species, confirmed its generic placement. A phylogenetic study also indicated clearly that the fungus on M. leuconeura is phylogenetically distinct from related species of this genus, leading to the proposal of the new species Bipolaris marantae.