Brevistachys wurfbainiae C. F. Liao, K. D. Hyde & Doilom, 2025

Brevistachys wurfbainiae C. F. Liao, K. D. Hyde & Doilom sp. nov.

Fig. 2 View Figure 2

Etymology.

In reference to the host genus Wurfbainia, from which the holotype was isolated.

Holotype.

MHZU 23-0254 .

Description.

Saprobic on dead stem of Wurfbainia villosa . Sexual morph: undetermined. Asexual morph: Colonies superficial on host substrate, effuse, hairy, gregarious, with numerous dark conidia on the substrate visible as black granular powder. Conidiophores 80–235 × 3–5.5 µm (av. 155 × 4.5 μm, n = 20), macronematous, mononematous, erect, simple, unbranched, straight or flexuous, subcylindrical, unevenly olivaceous brown, 1–3 - septate, not constricted at the septa, smooth-walled to finely verruculose in the above half, thick-walled, with bulbous apices, bearing 5–8 conidiogenous cells at the tip, often intermixed with setiferous, flexuous, sterile filaments. Setae 230–390 × 3–6 µm (av. 305 × 4.5 μm, n = 20), arising from the basal stroma, adjacent to cells that give rise to fertile conidiophores, unbranched, straight, and subhyaline at base, mostly flexuous, olivaceous green, in above half, moderately thick-walled, smooth, septate, acute at apex. Conidiogenous cells 6–10 × 4–7 µm (av. 7.5 × 5.5 μm, n = 30), enteroblastic, monophialidic, discrete, determinate, terminal, elongate doliiform, pale to dark brown, smooth-walled, with a conspicuous collarette. Conidia 5–9 µm diam. (av. 7 μm, n = 30), acrogenous, solitary, dry, obovoid to subglobose, aseptate, hyaline, and smooth-walled when young, pale brown, mostly olivaceous to dark brown, verrucose to warty-surfaced at maturity.

Culture characteristics.

Colonies on PDA reaching 2 cm in two weeks at 28 ± 2 ° C, medium dense, raised, sparse, filamentous, floccose to fluffy, velvety, filiform at margin, cream to pale brown from above; brown to pale luteous from reverse.

Material examined.

China • Guangdong Province, Yangchun City, Yongning Town (22.256185 ° N, 111.609037 ° E, 270 m), on dead stems of Wurfbainia villosa (Lour.) Škorničk. & A. D. Poulsen. ( Zingiberaceae ), 10 April 2022, C. F. Liao & Y. H. Yang, YAM 16 ( MHZU 23-0254 , holotype) • ex-type, ZHKUCC 23-1011 GoogleMaps • ibid., living culture ZHKUCC 23-1012 , and ZHKUCC 23-1013 GoogleMaps .

Notes.

Brevistachys wurfbainiae differs from other known species in the genus Brevistachys by having erect to flexuous, sterile, setiferous filaments intermixed with fertile conidiophores. Brevistachys wurfbainiae resembles B. subsimplex but differs from the latter in having slightly longer conidiophores with bulbous apices (80–235 × 3–5.5 µm vs. 80–200 (most frequently 100–140) × 3–5.5 µm) and shorter conidiogenous cells (6–10 × 4–7 µm vs. 8–13 × 4–6 µm). The conidiophores of B. wurfbainiae are 1–3 - septate, while they are 2–6 - septate in B. subsimplex ( Deighton 1960) . The phylogenetic analyses revealed that B. wurfbainiae ( ZHKUCC 23-1011 , ZHKUCC 23-1012 , and ZHKUCC 23-1013 ) formed a separate branch from B. subsimplex (ex-type CBS 100155) with 75 % ML bootstrap support and 0.93 BYPP (Fig. 1 View Figure 1 ). Based on distinct morphology and phylogenetic support, we propose B. wurfbainiae as a new species.