Tree inhabiting gnomoniaceous species from China, with Cryphogonomonia gen. nov. proposed

A new study of Nagrajomyces: with two new species proposed and taxonomic status inferred by phylogenetic methods

Nagrajomyces (incertae sedis, Ascomycota) is a monotypic genus with a previously unknown systematic position. In this report, two new species are proposed, Nagrajomycesfusiformis and Nagrajomyceslaojunshanensis. These new taxa are proposed based on morphological characteristics evident via light microscopy and molecular data. Multi-locus phylogenetic analyses (ITS rDNA, nrLSU rDNA, RPB2, and TEF1-α) show that specimens recently collected in Yunnan Province, China are closely related to Gnomoniaceae. Both new species and known species were discovered repeatedly in their asexual developmental form exclusively on twigs of Rhododendron spp. (Ericaceae). This indicates a host specificity of Nagrajomyces spp. for species of Rhododendron.

Morphological and Phylogenetic Analyses Reveal Four New Species of Gnomoniopsis (Gnomoniaceae, Diaporthales) from China

The fungal genus Gnomoniopsis (Gnomoniaceae, Diaporthales) has been reported all around the world and isolated from multiple plant hosts. Based on multilocus phylogenies from a combined dataset of internal transcribed spacer (ITS) region, the ribosomal RNA gene cluster, and partial regions of translation elongation factor 1 alpha (tef1) and partial beta-tubulin (tub2), in conjunction with morphological characteristics, we describe and illustrate herein four new species, including Gnomoniopsisdiaoluoshanensis sp. Nov., G. lithocarpi sp. Nov., G. mengyinensis sp. Nov. and G.yunnanensis sp. Nov. Alongside this, their similarity and dissimilarity to morphologically-allied and phylogenetically-related species are annotated and discussed. For facilitating future identification, we update the key to all species currently recognized in this genus.

Morphology and Phylogeny of Gnomoniopsis (Gnomoniaceae, Diaporthales) from Fagaceae Leaves in China

Gnomoniopsis (Gnomoniaceae, Diaporthales) is a well-classified genus inhabiting leaves, branches and fruits of the hosts in three plant families, namely Fagaceae, Onagraceae and Rosaceae. In the present study, eighteen Gnomoniopsis isolates were obtained from diseased leaves of Fagaceae hosts collected from Fujian, Guangdong, Hainan, Henan, Jiangxi and Shaanxi provinces in China. Morphology from the cultures and phylogeny based on the 5.8S nuclear ribosomal DNA gene with the two flanking internally transcribed spacer (ITS) regions, the translation elongation factor 1-alpha (tef1) and the beta-tubulin (tub2) genes were employed to identify these isolates. As a result, seven species were revealed, viz. Gnomoniopsis castanopsidis, G. fagacearum, G. guangdongensis, G. hainanensis, G. rossmaniae and G. silvicola spp. nov, as well as a known species G. daii. In addition, G. daii was firstly reported on the host Quercus aliena.

Micromelanconis kaihuiae gen. et sp. nov., a new diaporthalean fungus from Chinese chestnut branches in southern China

Melanconis-like fungi are distributed in several families of Diaporthales, mainly Juglanconidaceae, Melanconidaceae, Melanconiellaceae and Pseudomelanconidaceae. A new Melanconis-like genus of Pseudomelanconidaceae was discovered on branches of Chinese chestnut (Castanea mollissima) in southern China, which was confirmed by both morphology and phylogenetic analysis of combined ITS, LSU, tef1a and rpb2 sequences. The new genus Micromelanconis is characterized by two types of conidia from natural substrate and manual media of PDA, respectively. Conidia from Chinese chestnut branches are pale brown, ellipsoid, multiguttulate, aseptate with hyaline sheath. While conidia from PDA plates are pale brown, long dumbbell-shaped, narrow at the middle and wide at both ends, multiguttulate, aseptate, and also with hyaline sheath. All Pseudomelanconidaceae species were only reported on tree branches in China until now. More interesting taxa may be discovered if detailed surveys on tree-inhabiting fungi are carried out in East Asia in the future.