Pseudohelicomyces hyalosporus Y.Z. Lu, J.K. Liu & K.D. Hyde
Index Fungorum number: IF 554888; Facesoffungi number: FoF 04812
Etymology: “hyalosporus” referring to hyaline helicoid conidia of this fungus.
Holotype: HKAS 83995
Saprobic on submerged decaying wood. Sexual morph: Undetermined. Asexual morph: 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 conidia. Conidiophores pale brown, micronematous, mononematous, septate, branched, 26–53 μm (x̄ = 39.5 μm, SD = 13.5, n = 10) long, 4-5 μm (x̄ = 4.5 μm, SD = 0.5, n = 10) wide, smooth-walled. Conidiogenous cells holoblastic, monoblastic, integrated, smooth, each with single conidium. Conidia 126.5–237.5 μm (x̄ = 182 μm, SD = 55.5, n = 20) long, 4–7 μm (x̄ = 5.5 μm, SD = 1.5, n = 20) wide, helicoid, with conidial filament loosely coiled 1-2½ times, rounded at apical end, pale brown, smooth-walled.
Material examined: CHINA, Yunnan Province, saprobic on decaying wood submerged in a stream in Cangshan Mountain, March 2014, Z.L. Luo, S-051 (HKAS 83995, reference specimen designated here), living culture, MFLUCC 15-0343; Langcang River, April 2015, X.C. Tao, S-305 (HKAS 92825), living culture, KUMCC 15-0322; Jinsha River, April 2015, Z.L. Luo, JSJ H 5-1-1 (DLU 292), living culture, KUMCC 15-0430; Dulong River, May 2015, X.C. Tao, HD1-10-8 (DLU 509), living culture, KUMCC 15-0281; Jinsha River, April 2015, X.J. Su, JSJ H 25-18-1 (DLU 383), living culture, KUMCC 15-0411.
Notes: This taxon was introduced as Helicomyces roseus by Luo et al. (2017) based on its morphological similarities to H. roseus and its DNA sequence data are identical to H. roseus (CBS 283.51). However, the morphology of isolate CBS 283.51 does not tally to previous descriptions of H. roseus in conidiophores and conidia (Link 1809; Linder 1929; Goos 1985). Therefore, we consider that H. roseus CBS 283.51 have been wrongly identified. Furthermore, six isolates of H. roseus form a subclade which share a sister relationship to Pseudohelicomyces talbotii with good bootstrap support (99% MLBS, 1.00 PP) (Fig. 2). We also found those isolates in Clade 4 correspond to Helicomyces, thus, we reappraise these six isolates as Pseudohelicomyces hyalosporus. We designate the specimen HKAS 83995 as holotype as Luo et al. (2017) designated this as reference specimen. Pseudohelicomyces hyalosporus differs to other Pseudohelicomyces by having shorter conidiophores and larger conidia. (Notes from Luo et al. 2018)
Freshwater distribution: China (Luo et al. 2017)