Aquastroma magniostiolatum Kaz. Tanaka & K. Hiray., Studies in Mycology 82: 115 (2015)

Index Fungorum number: IF828557

Saprobic on dead wood. Asexual morph: Undetermined. Sexual morph: Ascomata 176–241 μm diam., 146–206 μm high, black domes visible on host cortex, solitary to gregarious, elliptical. Peridium thick-walled, pale brown cells of textula angularis. Hamathecium 2–3.9 μm (x̅ = 3 μm, n = 22), broad, pseudoparaphyses embedded in a gelatinous matrix, hyaline, filiform, smooth-walled, transverse septate. Asci 73.6–98.8 × 19–29 μm (x̅ = 84 × 23 μm, n = 20), 8-spored, fissitunicate, pedicellate, clavate, bitunicate, short pedicellate, apically rounded with invisible ocular chamber, hyline. Ascospores 34–42.6 × 6.8–9.7 μm (x̅ = 38 × 8.5 μm, n = 30), partial overlapping, clavate to fusiform, guttulate to granular, straight to slightly curved, multiseptate, constricted at the septum, hyaline, smooth-walled, surrounded with mucilaginous sheath.

Culture characteristics – Ascospores germinated on PDA within 15h at room temperature (25–28 ºC), reaching 3.2 cm in 22 days, entire edge, greenish grey to black, no pigment produced, flat or effuse, without aerial mycelium, smooth hyphae.

Material examined – Thailand, Chiang Rai Province, Mae Fah Luang University, on dead wood culm, 5 August 2019, Jing-Yi Zhang, MFLU 20-0484, living culture, MFLUCC 20-0112.

GenBank numbers – LSU: MT772011, ITS: MT772005, TEF1-α: MT777678.

Known distribution (based on molecular data) – Japan (Tanaka et al. 2015) and Thailand (this study).

Known hosts (based on molecular data) – Dead wood culms (Tanaka et al. 2015), this study).

Notes – Aquastroma magniostiolata was introduced by Tanaka et al. (2015) based on a specimen collected from Japan. A new sample (MFLU 20-0484) was collected from Thailand for the first time in this study. Multi-gene phylogenetic analyses of the combined LSU, SSU, ITS and TEF1-α sequence data indicated that MFLU 20-0484 is conspecific with Aquastroma magniostiolata (KT 2485) (100% MLBP/1.00 BYPP/100% MP). MFLU 20-0484 is similar to KT 2485 in morphology. Furthermore, MFLU 20-0484 has consistent base pairs with KT 2485 based on a comparison of LSU and ITS, while 6 base pair differences were observed in TEF1-α sequences (Jeewon & Hyde 2016).