Halocryptovalsa Dayarathne & K.D.Hyde, 2020

Dayarathne, Monika C., Wanasinghe, Dhanushka N., Devadatha, B., Abeywickrama, Pranami, G, E. B., Jones, areth, Chomnunti, Putarak, Sarma, V. V., Hyde, Kevin D., Lumyong, Saisamorn, C., Eric H. & Mckenzie, 2020, Modern taxonomic approaches to identifying diatrypaceous fungi from marine habitats, with a novel genus Halocryptovalsa Dayarathne & K. D. Hyde, gen. nov., Cryptogamie, Mycologie 20 (3), pp. 21-67 : 49-50

Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov.

MYCOBANK. — MB 824308.

FACESOFFUNGI NUMBER. — FoF 04597.

ETYMOLOGY. — Referring to the morphological resemblance to the genus Cryptovalsa and the saline environment from which the taxon was collected.

TYPE SPECIES. — Halocryptovalsa avicenniae (Abdel-Wahab, Bahkali & E.B.G.Jones) Dayarathne & K.D.Hyde , comb. nov.

DESCRIPTION

Saprobic on intertidal decayed wood of mangroves and decaying stems of salt marsh plants.

Sexual morph

Stromata. Poorly developed, flask-shaped, black, immersed in the surface layers of the host tissue, raising the surface of the substrate in little bumps, with protruding necks, substrate slightly modified between ascomata or more or less necrotic when they are close together.

Ascomata. Partially or deeply immersed in wide-spreading stroma, globose to subglobose, dark brown to black, single or aggregated and sometimes confluent, ostiolate, papillate.

Necks. 290-400 µm long, 270-290 µm wide, ostiolate, periphysate, with a small, globular-conical papilla immersed in a wide-spreading entostroma, which protrude above the substrate surface, lacking apical furrows.

Peridium. 11-52 µm wide, comprising an outer, brown, thick-walled layer of polygonal melanized cells, interspersed with cells of the substrate and inner, hyaline, thick-walled, several cell layers of textura angularis.

Hamathecium. Comprising aseptate, numerous paraphyses, narrowing and tapering towards the apex.

Asci. Multi-spored, unitunicate, with narrow, thin-walled pedicel, with cylindrical, thick-walled, swollen upper portion, apex flat, with J-, cylindrical, conspicuous apical or sub apical ring.

Ascospores. Hyaline or yellow-brown to brown, allantoid, straight or slightly curved, unicellular, thin-walled, with small, fat globules at the ends, smooth-walled.

Asexual morph

Pycnidia. Globose to subglobose, ostiolate, coriaceous, deeply immersed in a well-developed stroma with or without ascomata of the sexual stage.

Necks. Papillate, coriaceous.

Peridium. 12-22 µm thick around the pycnidial venter, onelayered, yellow-brown to brown, composed of polygonal cells with thick walls forming textura angularis.

Conidiophores. 0-2-septate, cylindrical, hyaline, simple or branched, with one or more conidiogenous cells.

Conidiogenous cells. Hyaline, unicellular, with wide base and tapering tip, producing one conidium, determinate. Conidiogenesis holoblastic.

Conidia. One-celled, filiform, straight, curved or hook-like, hyaline to yellowish and yellow/apricot in mass.

NOTES

Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., comprises cryptovalsa-like marine based diatrypaceous fungi with poorly developed stromata that lack horizontal or vertical furrows within the ascomatal necks. Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., can be clearly distinguish by having deeply immersed perithecia in the wood with relatively long, wide necks (290-430 µm long, 270-290 µm wide) while Cryptovalsa mostly comprises several ascomata arranged at different depth in the bark with relatively short necks ( Mehrabi et al. 2015). Necks of each ascoma of Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., appear as a small papilla protruding above the substrate, whereas protruding ascomatal necks of Cryptovalsa form a cluster of little bumps ( Mehrabi et al. 2015; Trouillas et al. 2015). Furthermore, the ascomatal outer surface of Cryptovalsa species is often with a white powdery entostroma ( Trouillas et al. 2015), while Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., species do not have a white powdery entostroma. Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., includes only marine derived taxa while Cryptovalsa species are prevalent in terrestrial habitats. Cryptovalsa halosarceiicola morphologically resembles Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., species, however, there are no sequence data in GenBank for Cryptovalsa halosarceiicola to confirm its phylogenetic relationship to our new genus. In our combined analysis of ITS+Btub the new genus formed a separate lineage with low statistical support ( Fig. 1 ). In ITS phylogeny Halocryptovalsa avicenniae , comb. nov., grouped in a clade with Diatrypasimilis australiensis ( Fig. 2 ). However, 117 bp are different out 522 bp between Halodiatrype avicenniae and D. australiensis in ITS loci. Therefore, depending on the combined phylogenetic analyses data and considerable morphological differences of this taxon to all the other genera in Diatrypaceae , we introduce the genus Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov., to accommodate Halocryptovalsa avicenniae , comb. nov., and Halocryptovalsa salicorniae Dayarathne & K.D.Hyde , sp. nov.

Figures

FIG. 1. — Phylogram generated from the best scoring RAxML tree based on combined ITS and Btub sequence data. Bootstrap support values for maximum likelihood (ML,black) and maximum parsimony (MP, blue) equal or greater than 60 % are given above the nodes. Bayesian posterior probabilities (PP,green) equal or greater than 0.90 are shown above the branch. The tree is rooted to Xylaria hypoxylon (CBS 122620) and Kretzschmaria deusta (CBS 826.72). All sequences from ex-type strains are in bold. Symbols:, polysporous species;, octosporous species;, species with less than eight spores. Scale bar: 0.2 (expected number of nucleotide substitutions per site per branch).

FIG. 2. — Phylogram generated from the best scoring RAxML tree based on ITS sequence data. Bootstrap support values for maximum likelihood (ML, black) and maximum parsimony (MP, blue) equal or greater than 60% are given above the nodes. Bayesian posterior probabilities (PP,green) equal or greater than 0.90 are shown above the branch. The tree is rooted to Xylaria hypoxylon (CBS 122620) and Kretzschmaria deusta (CBS 826.72). Scale bar: 0.09 (expected number of nucleotide substitutions per site per branch).