Neohelicomyces hydei J. Ma, Y. Z. Lu & K. D. Hyde 2024, sp. nov.
Creators: name: Ma, Jian
name: Gomdola, Deecksha
name: Boonmee, Saranyaphat
name: Shen, Hong-Wei
name: Tang, Xia
name: Zhang, Li-Juan
name: Lu, Yong-Zhong
name: Hyde, Kevin D.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Dothideomycetes
Tubeufiales
Tubeufiaceae
Neohelicomyces
Neohelicomyces hydei

description: Neohelicomyces hydei J. Ma, Y. Z. Lu & K. D. Hyde sp. nov.
Fig. 4
Etymology.
The epithet “ hydei ” is named in honour of Prof. Kevin D. Hyde for his contributions to mycology.
Holotype.
HKAS 134925.
Description.
Saprobic on decaying wood in a freshwater habitat. Sexual morph Unknown from natural habitat. Asexual morph Hyphomycetous, helicosporous. Colonies on natural substrate superficial, effuse, gregarious, white to pale brown. Mycelium semi-immersed, hyaline to pale brown, septate, branched hyphae, smooth, comprising glistening conidial mass. Conidiophores 262–410 μm long, 5.5–7 μm wide (x ¯ = 335 × 6 μm, n = 30), macronematous, mononematous, erect, flexuous, cylindrical, branched, up to 20 – septate, hyaline to pale brown, smooth, thick-walled. Conidiogenous cells 7.5–19.5 μm long, 3.5–6 μm wide (x ¯ = 16.5 × 4 μm, n = 35), holoblastic, monoblastic to polyblastic, integrated, intercalary or terminal, cylindrical, with a denticulate protrusion, truncate at apex after conidial secession, hyaline to pale brown, smooth-walled. Conidia solitary, acropleurogenous, helicoid, rounded at tip, up to 18.5 μm in diameter and conidial filaments 2–3 μm wide, 137.5–171.5 μm long (x ¯ = 158 μm, n = 25), indistinctly multiseptate, coiled up to 4 times, becoming loosely coiled in water, guttulate, hyaline, smooth-walled.
Culture characteristics.
Conidia producing germ tubes on PDA within 12 hours of incubation at 25 ° C. Colonies on PDA are circular with umbonate surface and entire edge, reaching 42 mm in diameter after 50 days of incubation at 25 ° C, top view of colony brown to black brown, reverse pale brown to black brown.
Material examined.
China, Guizhou Province, Qianxinan Buyi and Miao Autonomous Prefecture, Xianheping National Forest Park, 24 ° 97 ′ N, 105 ° 63 ′ E, on decaying wood in a freshwater habitat, 16 March 2022, Jian Ma, XHP 1 (HKAS 134925, holotype; GZAAS 23–0621, isotype), ex-type living cultures GZCC 23–0727; Ibid., XHP 1.1 (GZAAS 23–0622, paratype), living culture GZCC 23–0728.
Notes.
Our isolates, GZCC 23–0727 and GZCC 23–0728 cluster together and form a sister clade to N. aquaticus (MFLUCC 16–0993 and KUMCC 15–0463) with 96 % ML / 0.95 PP support. Upon comparison of the nucleotide bases between our isolates and Neohelicomyces aquaticus (MFLUCC 16–0993), the following differences were observed: 1 / 851 bp (0.1 %, including 1 gap) across LSU, 13 / 869 bp (1.5 %, including 1 gap) across tef 1 α and 46 / 945 bp (4.9 %, with no gaps) across rpb 2. Unfortunately, we were unable to compare the differences in nucleotide bases across ITS as our isolates (GZCC 23–0727 and GZCC 23–0728) lack ITS sequence data. Despite several trials using different PCR conditions, we were unable to amplify the ITS locus for our strain (GZCC 23–0727 and GZCC 23–0728) successfully. Morphologically, our isolates (GZAAS 23–0621 and GZAAS 23–0622) differ from N. aquaticus (MFLU 16–2543) as they have mostly branched and hyaline conidiophores, polyblastic, terminal and hyaline conidiogenous cells and acropleurogenous conidia (Luo et al. 2017). Based on phylogenetic placement and morphology, we identify GZCC 23–0727 and GZCC 23–0728 as a single species, Neohelicomyces hydei.
description: Published as part of Ma, Jian, Gomdola, Deecksha, Boonmee, Saranyaphat, Shen, Hong-Wei, Tang, Xia, Zhang, Li-Juan, Lu, Yong-Zhong & Hyde, Kevin D., 2024, Three new species of Neohelicomyces (Tubeufiales, Tubeufiaceae) from freshwater and terrestrial habitats in China, pp. 317-336 in MycoKeys 105 on pages 317-336, DOI: 10.3897/mycokeys.105.124129