Three Novel Entomopathogenic Fungi From China and Thailand

Diversity of soil fungi and entomopathogenic fungi in subtropical mountain forest in southwest China

Till now, the diversity of entomopathogenic fungi in subtropical mountain forest was less studied. Here, the vertical distribution of forest soil fungi, entomopathogenic fungi, and their environmental influencing factors in a subtropical mountain in western China were investigated. Soil samples were collected from four elevations in a subtropical forest in Shaanxi. The results indicated a greater richness of soil fungi at middle elevations and soil fungi were more even at low elevation. Soil pH, available iron, available potassium, total potassium, and available zinc were the most important influencing factors affecting this vertical distribution of fungi. Interestingly, the Isaria genus was predominant while Metarhizium and Beauveria showed decreasing abundance. The presence of Isaria showed a significant positive correlation with both total phosphorus and available iron, while, available zinc was negatively correlated. Metarhizium was influenced by elevation, pH, available phosphorus, and available copper and Beauveria was influenced by soil organic carbon, total nitrogen, total potassium, available potassium, and available zinc. Overall, as environmental factors affecting soil fungi, elevation, and plant species diversity were less important than soil physical and chemical properties. The virulence of isolated entomopathogenic fungi were tested against larvae of Tenebrio molitor, with mortality ranging from 31.11% to 100%. The above findings provide valuable data to deepen our understanding of the diversity of entomopathogenic fungi in subtropical mountain forests.

Two new species and one new combination of Ophiocordyceps (Hypocreales, Ophiocordycipitaceae) in Guizhou

Ophiocordyceps is the largest genus in Ophiocordycipitaceae and has a broad distribution with high diversity in subtropical and tropical regions. In this study, two new species, pathogenic on lepidopteran larvae are introduced, based on morphological observation and molecular phylogeny. Ophiocordycepsfenggangensissp. nov. is characterised by having fibrous, stalked stroma with a sterile tip, immersed perithecia, cylindrical asci and filiform ascospores disarticulating into secondary spores. Ophiocordycepsliangiisp. nov. has the characteristics of fibrous, brown, stipitate, filiform stroma, superficial perithecia, cylindrical asci and cylindrical-filiform, non-disarticulating ascospores. A new combination Ophiocordycepsmusicaudata (syn. Cordycepsmusicaudata) is established employing molecular analysis and morphological characteristics. Ophiocordycepsmusicaudata is characterised by wiry, stipitate, solitary, paired to multiple stromata, yellowish, branched fertile part, brown stipe, immersed perithecia, cylindrical asci and cylindrical-filiform, non-disarticulating ascospores.

Four novel Pleurocordyceps (Polycephalomycetaceae) species from China

Entomopathogenic fungi comprise an ecologically important group of specialized pathogens infecting other fungi, invertebrates, and plants. These fungi are species-rich with high diversity and broad distribution worldwide. The majority of entomopathogenic fungi belong to clavicipitoids, which consist of the hypocrealean families, Clavicipitaceae, Cordycipitaceae, Ophiocordycipitaceae, and Polycephalomycetaceae. The latter is a newly established entomopathogenic family that recently separated from the family Ophiocordycipitaceae to accommodate the genera, Perennicordyceps, Pleurocordyceps, and Polycephalomyces. In recent years, Polycephalomycetaceae has been enriched with parasitic and hyperparasitic fungi. With 16 species spread across China, Ecuador, Japan, and Thailand, Pleurocordyceps is the most speciose genus in the family. In this study, we expand the number of taxa in the genus by introducing four new Pleurocordyceps species from China, namely, P. clavisynnema, P. multisynnema, P. neoagarica, and P. sanduensis. We provide detailed descriptions and illustrations and infer genus-level phylogenies based on a combined 6-loci gene sequence dataset comprising the internal transcribed spacer gene region (ITS), small subunit ribosomal RNA gene region (SSU), large subunit rRNA gene region (LSU), translation elongation factor 1-alpha gene region (TEF-1α), RNA polymerase II largest subunit gene region (RPB1), and RNA polymerase II second largest subunit (RPB2). This study contributes to knowledge with regard to the diversity of Pleurocordyceps specifically and entomopathogenic Hypocreales more broadly.

New species and new combinations in the genus Paraisaria (Hypocreales, Ophiocordycipitaceae) from the U.S.A., supported by polyphasic analysis

Molecular phylogenetic and chemical analyses, and morphological characterization of collections of North American Paraisaria specimens support the description of two new species and two new combinations for known species. P.cascadensissp. nov. is a pathogen of Cyphoderris (Orthoptera) from the Pacific Northwest USA and P.pseudoheteropodasp. nov. is a pathogen of cicadae (Hemiptera) from the Southeast USA. New combinations are made for Ophiocordycepsinsignis and O.monticola based on morphological, ecological, and chemical study. A new cyclopeptide family proved indispensable in providing chemotaxonomic markers for resolving species in degraded herbarium specimens for which DNA sequencing is intractable. This approach enabled the critical linkage of a 142-year-old type specimen to a phylogenetic clade. The diversity of Paraisaria in North America and the utility of chemotaxonomy for the genus are discussed.

Insight into the Systematics of Novel Entomopathogenic Fungi Associated with Armored Scale Insect, Kuwanaspis howardi (Hemiptera: Diaspididae) in China

This study led to the discovery of three entomopathogenic fungi associated with Kuwanaspis howardi, a scale insect on Phyllostachys heteroclada (fishscale bamboo) and Pleioblastus amarus (bitter bamboo) in China. Two of these species belong to Podonectria: P. kuwanaspidis X.L. Xu & C.L. Yang sp. nov. and P. novae-zelandiae Dingley. The new species P. kuwanaspidis has wider and thicker setae, longer and wider asci, longer ascospores, and more septa as compared with similar Podonectria species. The morphs of extant species P. novae-zelandiae is confirmed based on sexual and asexual morphologies. Maximum likelihood and Bayesian inference analyses of ITS, LSU, SSU, tef1-α, and rpb2 sequence data provide further evidence for the validity of the two species and their placement in Podonectriaceae (Pleosporales). The second new species, Microcera kuwanaspidis X.L. Xu & C.L. Yang sp. nov., is established based on DNA sequence data from ITS, LSU, SSU, tef1-α, rpb1, rpb2, acl1, act, cmdA, and his3 gene regions, and it is characterized by morphological differences in septum numbers and single conidial mass.