Introducing Seriascoma yunnanense sp. nov. (Occultibambusaceae, Pleosporales) based on evidence from morphology and phylogeny

Abstract

In this study, we introduce a new fungal species from dead branches of bamboo (Poaceae) in Yunnan Province, China. Combined LSU, SSU, RPB2 and TEF1-α gene sequence data analysis showed it belongs to the family Occultibambusaceae (Pleosporales). Maximum likelihood and Bayesian analyses were performed to clarify the phylogenetic affinities of the taxon. The novel species is typical to Seriascoma in its elongated, gregarious, ostiolate ascostromata, immersed beneath the clypeus and clavate to fusiform, didymosporous, hyaline ascospores, but differs from S. didymospora in having uni-loculate ascostromata, short pedicellate asci and ascospores with gelatinous sheath and relatively large guttules. The new taxon is compared with known Seriascoma species and a comprehensive description and micrographs are provided.

A Taxonomic Appraisal of Bambusicolous Fungi in Occultibambusaceae (Pleosporales, Dothideomycetes) with New Collections from Yunnan Province, China

“…Occultibambusaceae is characterized by solitary, immersed, subglobose to conical, greyish to dark brown, uni- or multi-loculate ascostromata, scattered or in small groups, with papillate, or protruding ostioles, bitunicate, fissitunicate, (6)–8-spored, cylindrical to clavate asci with short, furcate or bulb-like pedicels, and 1–3-seriate, fusiform, hyaline, or pale brown to dark brown, 1–3-septate ascospores with or without a sheath [ 1 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. Brunneofusispora , Occultibambusa , Seriascoma , and Versicolorisporium were reported to have coelomycetous asexual morphs [ 4 , 14 , 15 , 16 ], while Neooccultibambusa forms chlamydospores in culture or has as hyphomycetous asexual morphs [ 6 , 9 , 17 ].…”

“…Occultibambusaceae is a small family with 18 species [ 18 ]. To date, this family has been reported from China, Italy, Japan, and Thailand [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 19 ]. With the exception of species of Neooccultibambusa and Brunneofusispora , most species of Occultibambusaceae are saprobes on dead bamboo [ 4 , 8 , 10 , 12 , 13 ].…”

“…To date, this family has been reported from China, Italy, Japan, and Thailand [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 19 ]. With the exception of species of Neooccultibambusa and Brunneofusispora , most species of Occultibambusaceae are saprobes on dead bamboo [ 4 , 8 , 10 , 12 , 13 ]. Neooccultibambusa has been found on a wide variety of hosts such as Ammophila sp., Pandanus sp.…”

“…Dai & K.D. Hyde and is characterized by solitary or gregarious, raised, immersed, subglobose to conical, dark brown, uni-loculate, coriaceous ascostromata with black, papillate ostioles, bitunicate, fissitunicate, eight-spored, broadly cylindrical to clavate asci, and fusiform, pale brown to brown, 1–(3)-septate ascospores, with or without a sheath [ 4 , 8 , 10 , 12 , 13 ]. Eight species are accommodated in Occultibambusa [ 18 ].…”

Morpho-Phylo Taxonomy of Novel Dothideomycetous Fungi Associated With Dead Woody Twigs in Yunnan Province, China

“…However, woody-based microfungi such as Dothideomycetes are relatively neglected compared to the level of research conducted on Basidiomycetes (Wanasinghe et al, 2020). In the last few years, there has been increasing attention on woody-based microfungal occurrences, and more studies are reporting on the microfungal diversity, especially in Dothideomycetes, of Yunnan Province (Bao et al, 2018;Huang et al, 2018;Luo et al, 2018;Wanasinghe et al, 2018aWanasinghe et al, , 2020Wanasinghe et al, , 2021Rathnayaka et al, 2019;Qiao et al, 2020;Thiyagaraja et al, 2020b;Yasanthika et al, 2020).…”