Neohelicomyces
Neohelicomyces Z.L. Luo, Bhat & K.D. Hyde
Index Fungorum number: IF 818820; Facesoffungi number: FoF 02643
Saprobic on submerged decaying wood. Sexual morph: Undetermined. Asexual morph: Hyphomycetous, helicosporous. Colonies on the substratum superficial, effuse, gregarious, white. Mycelium composed of partly immersed, partly superficial, hyaline to pale brown, septate, sparsely branched hyphae, with masses of crowded, glistening conidia. Conidiophores macronematous, mononematous, erect, septate, sparsely branched, arising directly on substrate, glistening, hyaline to pale brown, smooth-walled. Conidiogenous cells holoblastic, mono- to polyblastic, integrated, cylindric, with lateral minute denticles, hyaline to pale brown, smooth-walled. Conidia solitary, acropleurogenous, helicoid, rounded at tip, with conidial filament tightly coiled, becoming loose in water, indistinctly multi-septate, guttulate, hyaline, smooth-walled. (Description from Lu et al. 2018)
Type species: Neohelicomyces aquaticus Z.L. Luo, Bhat & K.D. Hyde
Notes: Neohelicomyces was introduced by Luo et al. (2017) for three freshwater species. Lu et al. (2018) introduced the fourth freshwater species N. hyalosporus Y.Z. Lu et al. which differs from the others in having longer conidiophores and hyaline conidia. Neohelicomyces is characterized by white colonies, macronematous, branched conidiophores, mono- to poly-blastic, integrated conidiogenous cells with lateral minute denticles and helicoid conidia (Luo et al. 2017). Two strains Tubeufia amazonensis Samuels et al. (ATCC 42524) and T. helicomyces Höhn. (MUCL 15702) cluster in Neohelicomyces (Lu et al. 2018; Dong et al. 2020) but are not synonymized because they lack morphology (Tsui et al. 2006). We introduce another two freshwater Neohelicomyces species collected from Thailand and China. (Notes from Dong et al. 2020)
List of freshwater Neohelicomyces species
Neohelicomyces aquaticus Z.L. Luo, Bhat & K.D. Hyde, Cryptog. Mycol. 38(1): 40 (2017)
Freshwater distribution: China (Luo et al. 2017)
Neohelicomyces dehongensis H. Zhang, W. Dong & K.D. Hyde
Freshwater distribution: China (Dong et al. 2020)
Neohelicomyces
grandisporus Z.L. Luo, Boonmee & K.D. Hyde, Cryptog. Mycol. 38(1): 44 (2017)
Freshwater distribution: China (Luo et al. 2017)
Neohelicomyces hyalosporus Y.Z. Lu, J.C. Kang & K.D. Hyde, Fungal Diversity 92: 225 (2018)
Freshwater distribution: China (Lu et al. 2018)
Neohelicomyces submersus Z.L. Luo, H.Y. Su & K.D. Hyde, Cryptog. Mycol. 38(1): 40 (2017)
Freshwater distribution: China (Luo et al. 2017)
Neohelicomyces thailandicus H. Zhang, W. Dong & K.D. Hyde
Freshwater distribution: Thailand (Dong et al. 2020)
Key to freshwater Neohelicomyces species
1. Conidiophores < 170 μm long................................................. N. grandisporus
1. Conidiophores > 170 μm long...................................................................... 2
2. Conidia hyaline........................................................................................... 3
2. Conidia pale brown..................................................................................... 5
3. Conidia > 20 μm diam............................................................ N. dehongensis
3. Conidia < 20 μm diam................................................................................. 4
4. Conidia pleurogenous............................................................. N. thailandicus
4. Conidia acropleurogenous....................................................... N. hyalosporus
5. Conidiophores 240.5–335.5 μm, conidia coiled 2–2.5 times.......... N. aquaticus
5. Conidiophores 172–285 μm, conidia coiled 3–3.5 times.............. N. submersus
References
Luo ZL, Bhat DJ, Jeewon R, Boonmee S, Bao DF, Zhao YC, Chai HM, Su HY, Su XJ, Hyde KD (2017) Molecular phylogeny and morphological characterization of asexual fungi (Tubeufiaceae) from freshwater habitats in Yunnan, China. Cryptogam Mycol 38:27–53. https://doi.org/10.7872/crym/v38.iss1.2017.27
Lu YZ, Liu JK (Jack), Hyde KD, Jeewon R, Kang JC, Fan C, Boonmee S, Bhat DJ, Luo ZL, Lin CG, Eungwanichayapant PD (2018) A taxonomic reassessment of Tubeufiales based on multi-locus phylogeny and morphology. Fungal Divers 92:131–344. https://doi.org/10.1007/s13225-018-0411-y
Tsui CKM, Sivichai S, Berbee ML (2006) Molecular systematics of Helicoma, Helicomyces and Helicosporium and their teleomorphs inferred from rDNA sequences. Mycologia 98:94–104. https://doi.org/10.1080/15572536.2006.11832715
Recent Genus
1Neochlamydotubeufia
Neohelicomyces
Recent Species
Neohelicomyces submersusNeohelicomyces hyalosporus
Neohelicomyces grandisporus