Pseudobactrodesmium (Dactylosporaceae, Eurotiomycetes, Fungi) a Novel Lignicolous Genus.

Wei Dong,Mingkwan Doilom,Rajesh Jeewon,Saranyaphat Boonmee,Kevin D Hyde,Xian-Dong Yu,D Jayarama Bhat,Sarunya Nalumpang,Huang Zhang,Gen-Nuo Wang

doi:10.3389/fmicb.2020.00456

Abstract

During our ongoing surveys of fungi on submerged wood in the Greater Mekong Subregion, we collected two new species similar to Bactrodesmium longisporum. Pseudobactrodesmium gen. nov. is introduced to accommodate the new species, P. aquaticum, P. chiangmaiensis and B. longisporum is transferred to this genus. Fasciculate conidiophores, enteroblastic conidiogenous cells and subulate to fusiform, phragmoseptate conidia with a tapering apical cell and sheath characterize the genus. Pseudobactrodesmium aquaticum has longer conidia than P. chiangmaiensis. The placement of Pseudobactrodesmium in Dactylosporaceae (Eurotiomycetes) is a novel finding based on analyses of combined LSU, SSU, ITS and RPB2 sequence data. Our study reveals that Pseudobactrodesmium is likely to be a speciose genus with different species in streams around the world.

Highlights

Dactylosporaceae accommodates ecologically and morphologically diverse genera, and was reinstated by Diederich et al (2018) to replace Sclerococcaceae (Réblová et al, 2016)
Bactrodesmium longisporum has been recorded as having a worldwide distribution, these records have not been verified with molecular data
We designate our new species of Pseudobactrodesmium from China as the generic type, describe a second species from Thailand and transfer Bactrodesmium longisporum to the new genus

Summary

Introduction

Dactylosporaceae accommodates ecologically and morphologically diverse genera, and was reinstated by Diederich et al (2018) to replace Sclerococcaceae (Réblová et al, 2016). The freshwater genus Cylindroconidiis has holoblastic conidiogenous cells (Yu et al, 2018), while the terrestrial genera Pseudosclerococcum and Rhopalophora are apothecial ascomycetes and dematiaceous phialidic hyphomycetes, respectively (Réblová et al, 2016; Olariaga et al, 2019). With more molecular data becoming available for phylogenetic analyses, numerous new combinations have been proposed to accommodate poorly documented hyphomycetous species (Lu et al, 2018; Yang et al, 2018a,b). The polyphyletic nature of some hyphomycetous genera were partially resolved, e.g., Dendryphion, Sporidesmium and torula-like species (Su et al, 2016), fresh collections with molecular data are still needed to obtain a natural classification of hyphomycetes

Methods

Results

Conclusion