Basionym: Didymella aptrootii K.D. Hyde & S.W. Wong, Australas. Mycol. 18 (3): 54 (1999)
Index Fungorum number: IF551686; Facesoffungi number: FoF 01273
Holotype: HKU(M) 3333
Saprobic on submerged wood in freshwater. Sexual morph: Ascomata 150–170 μm high, 190–220 μm diam., immersed or semi-immersed, scattered or clustered, lenticular, covered with a blackened pseudoclypeus, black, coriaceous, ostiolate. Peridium 10–15 μm thick, comprising several layers of brown, thin-walled, flattened cells of textura angularis. Pseudoparaphyses 2–2.5 μm wide, numerous, cellular, hyphae-like, hyaline, sparsely septate, unbranched. Asci 80–115 × 19–26 μm (x̅ = 95 × 22 μm, n = 10), 8-spored, bitunicate, fissitunicate, broadly clavate, with a long, straight or twisted pedicel and an ocular chamber. Ascospores 17.5–22 × 8–8.5 μm (x̅ = 19 × 8 µm, n = 15), bi- to tri-seriate, ellipsoidal to broadly fusiform, rounded at both ends, hyaline, 1-septate, constricted at the septum, the upper cell slightly broader and shorter than the lower cell, guttulate, thin-walled, surrounded by a large, irregular, mucilaginous sheath, 10–15 μm wide. Asexual morph: Undetermined. (Descriptions from Dong et al. 2020)
Culture characteristics: On PDA, colony circular, reaching 15 mm in 30 days at 25°C, black in inner layer and white in outer layer from above, black from below, surface fluffy, with fairly dense mycelium, raised, with a smooth edge.
Material examined: THAILAND, Phayao Province, on submerged wood in a stream, 23 February 2018, X.D. Yu, Y22 (MFLU 18-1000), living culture MFLUCC 18-0988.
Additional material examined: THAILAND, Chiang Rai Province, on submerged bamboo, 18 January 2010, H. Zhang (MFLU 10-0162).
Notes: Our new collection MFLUCC 18-0988 is identified as Longipedicellata aptrootii based on their identical LSU and ITS sequence data between MFLUCC 18-0988 and MFLUCC 10-0297, and phylogenetic analysis. Our collection has wider asci (80–115 × 19–26 μm vs. 70–100 × 17–20 μm) than the reference specimen in Zhang et al. (2016). We found numerous pseudoparaphyses in our collection, which were not mentioned in Zhang et al. (2016). (Notes from Dong et al. 2020)
Freshwater distribution: China (Hyde and Wong 1998), Malaysia (Hyde and Wong 1998), Philippines (Hyde and Wong 1998; Cai et al. 2003a), Thailand (Kurniawati et al. 2010; Zhang et al. 2016; this study)