Hypomyces sichuanensis Jing Z. Sun

Gajanayake, Achala J., Jayawardena, Ruvishika S. & Luangharn, Thatsanee, 2023, Revealing new records of hypocrealean fungicolous fungi from northern Thailand, Phytotaxa 630 (3), pp. 211-228 : 221

Hypomyces sichuanensis Jing Z. Sun , in Gu, Fu, Wang & Sun, Phytotaxa 516(1): 37 (2021) Fig 3

Index Fungorum number: IF558006, Facesoffungi Number: FoF 14743

Fungicolous on a fruiting body of a Bolete Sexual morph: not observed. Asexual morph: on the host, yellow color spore masses. On PDA, hyphomycetous, mycelium hyaline, septate, branched, growing in the form of floccose masses. Conidiophores 1.5–4 μm (x = 3 μm, n = 30) wide, hyaline, septate erect, flexuous, forming phialidic and aleuriogenic conidiogenous cells. Phialides solitary or forms 2–3 verticels 70–180 × 2–3.5 μm (x = 125 × 2.5 μm, n = 30), reducing the width to 1–2 μm at the terminal ends and produce phialoconidia. Phialoconidia 6.5–24 × 3–8 μm (x = 17 × 5.5 μm, n = 40), acrogenous, hyaline, ellipsoid to clavate, aseptate. Aleuriogenic conidiogenous cells discrete, forms on short or long side branches. Aleurioconidia 9.5–15 × 8.5–15 μm (x = 12 × 11.5 μm, n = 40), hyaline at immature stages and gradually turning light yellow to golden yellow with maturity, with angular, densely arranged cylindrical tubercles on the surface, subglobose to globose, thick-walled, aseptate.

Colony characters:—on PDA, at 25 °C, reached 50–60 mm after 14 days of incubation. Having a tomentose to pubescent appearance, initially white and then becoming yellowish and developing a powdery texture with the production of aleuroconidia, margins irregular.

Material examined:— Thailand, Chiang Rai Province, Mae Salong Nok, Mae Fa Luang, Chang Wat, isolated with the mycelium growing on a decaying fruiting body of a bolete, 18 June 2021, Gajanayake A.J, DM 04 (inactive dry culture MFLU 23-0421), living culture MFLUCC 23-0204.

GenBank accession numbers:—MFLUCC 23-0204: ITS: OR473186; LSU: OR473187; rpbb2: OR742381; tef1α: OR759136.

Notes:—In the phylogenetic analyses, our isolate MFLUCC 23-0204, clustered with Hypomyces sichuanensis strains CGMCC 3.20159 and CGMCC 3.20160 with 100% BS and 0.73 PP value. Furthermore, the morphological characteristics of our isolate MFLUCC 23-0204 described herein are similar to the original description and illustrations given by Gu et al. (2021). The phialides length and the phialoconidial size of MFLUCC 23-0204 are higher than those of H. sichuanensis described by Gu et al. (2021), whereas, the aleuroconidial size of H. sichuanensis described by Gu et al. (2021) is higher than MFLUCC 23-0204 described in this study: phialides: 125 × 2.5 μm vs. 115 × 2.5 μm, phialoconidia: 17 × 5.5 μm vs. 14.5 × 5 μm, aleuroconidia: 12 × 11.5 μm vs. 12.5 × 12 μm. These differences may have occurred due to the variations of the agar medium and the conditions used to obtain the cultures. Therefore, we confirmed that our isolate MFLUCC 23-0204 is H. sichuanensis . To the best of our knowledge, this is the first report of H. sichuanensis as a fungicolous fungus from Thailand, and this is the second documented record of H. sichuanensis since its’ introduction by Gu et al. (2021).

Figures

FIGURE 3. Hypomyces sichuanensis (MFLU 23-0421). a Host (Bolete). b, c Colony on PDA.e Sporulation on PDA.e–h Aleurioconidial attachments. i–l Phialoconidial attachments m Aleurioconidia. n Phialoconidia. Scale bars: b, c = 30 mm, d = 500 μm, f, g, i = 100 μm, m, n = 10 μm.