Halocryptovalsa salicorniae 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 : 52

Halocryptovalsa salicorniae Dayarathne & K.D.Hyde , sp. nov.

( Fig. 14 )

MYCOBANK. — MB 824309.

FACESOFFUNGI NUMBER. — FoF 03948.

ETYMOLOGY. — Referring to the host genus, Salicornia .

CULTURE CHARACTERS. — Reaching 2 cm within 7 days on PDA, when incubated at 25 °C, circular, flat, with diffuse margin, white, and becoming yellowish white, bright yellow to dull yellow with age.

MATERIAL EXAMINED. — Thailand, Chang Wat Prachuap Khiri Khan Province, Amphoe Bang Saphan, Tambon Thong Chai , on decaying Salicornia sp. stem, 16.VIII.2015, Monika Dayarathne, CHAM018 ( MFLU 16-0551 holotype); ex-type living culture, MFLUCC 15-0185 and ICMP.

DISTRIBUTION. — Thailand.

DESCRIPTION

Saprobic on decaying stem of Salicornia sp.

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. 230-300 µm high, 140-168 µm diam. (ẍ = 265 × 154 µm, n = 5), uni-perithecial, immersed in stromatic tissues, globose to subglobose, dark brown to black, ostiolate, papillate; papilla 76-90 µm high, 55-62 µm wide (ẍ = 83 × 58.5 µm, n = 20), globular-conical, immersed in a wide-spreading entostroma in the surface layers of the host tissue, periphysate.

Peridium. 11-16 µm wide (ẍ = 13 µm, n = 20), comprising an outer, brown, thick-walled layer, consisting of polygonal melanized cells, brown to dark-brown, interspersed with cells of the substrate; and inner, hyaline, thick-walled, several cell layers of textura angularis.

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

Asci. 87-95 × 9-13 µm (ẍ = 91 × 11 µm, n = 20), multispored, unitunicate, with narrow, thin-walled pedicel, with cylindrical, thick-walled, swollen upper portion, apex flat, with J-, cylindrical, conspicuous apical ring.

Ascospores. 3-5 × 1-2 µm (ẍ = 4 × 1.5 µm, n = 20), hyaline, allantoid, straight or slightly curved, unicellular, thin-walled, with small fat globules at the ends, smooth-walled.

Asexual morph

Undetermined.

NOTES

Phylogenetic analyses with ITS and ITS+Btub sequences of Halocryptovalsa salicorniae Dayarathne & K.D.Hyde , sp. nov., proved their conspecificity and placement in Diatrypaceae as a separate species from all other genera (clade J) ( Figs 1 ; 2 ). According to our phylogenetic analyses with ITS and combined ITS+Btub, stability of this genus within the family needs to be re-considered with more taxon sampling as taxa grouped in different positions. Our second analysis with LSU+SSU sequence data confirmed its phylogenetic relationship to Halocryptovalsa avicenniae , comb.nov. ( Figs 3 ; 4 ). Morphologically,they differ in length and colour of ascospores (5-8 µm, yellow-brown to brown in Hcr. avicenniae and3-5 µm, hyaline in Hcr. salicorniae ). Because Halocryptovalsa avicenniae , comb. nov., and Hcr. salicornia e and distantly placed from Cryptovalsa species, we accommodated these species in a new genus Halocryptovalsa Dayarathne & K.D.Hyde , gen. nov. Comparative morphological features of this species and Halocryptovalsa avicenniae , comb. nov., Cryptovalsa halosarceicola , C. mangrovei and C. suaedicola are summarized in Table 4 .

Figures

FIG. 14. — Halocryptovalsa salicorniae Dayarathne & K.D.Hyde, sp. nov. (MFLU 16-0551 – holotype): A, host (Salicornia sp.); B, C, appearance of ascostromata on host; D, horizontal section through ascostroma; E, section through neck region; F, peridium; G, H, asci; I, asci with paraphyses; J-M, ascospores; N, germinating ascospores; O, P, culture on PDA (O-upper, P-lower). Scale bars: B, 500 µm; D-F, 100 μm; G-I, 50 μm; J-N, 5 μm.

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).

FIG. 3. — Phylogram generated from the best scoring RAxML tree based on combined LSU and SSU sequence data. Bootstrap support values for maximum likelihood (ML, 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 branches. The tree is rooted to Xylaria hypoxylon (OCS 100004) and Xylaria acuta (5089). All sequences from ex-type strains are in bold. Scale bar: 0.02 (expected number of nucleotide substitutions per site per branch).

FIG. 4. — Phylogram generated from the best scoring MP tree based on combined LSU and SSU sequence data. Bootstrap support values for maximum parsimony (MP) equal or greater than 60 % are given above the nodes. The tree is rooted to Xylaria hypoxylon (OCS 100004) and Xylaria acuta (5089). Scale bar: 50 (expected number of nucleotide substitutions per site per branch).