Lentistoma aquaticum W. Dong, H. Zhang & K.D. Hyde
Index Fungorum number: IF 557918; Facesoffungi number: FoF 09260
Holotype: MFLU 18-1718
Etymology: Referring to aquatic habitat of this fungus
Saprobic on decaying wood submerged in freshwater. Sexual morph: Ascomata 270–320 μm high, 580–620 μm wide, black, scattered, immersed to erumpent, conical, carbonaceous, with ostiolate, short papilla. Peridium 50–70 μm at the sides, 20–30 μm at the base, comprising carbonaceous, occluded dark cells, easily cracked, flattened at the base. Pseudoparaphyses 3.5 μm wide, numerous, cellular, hypha-like, hyaline, distantly septate. Asci (90–)130–160 × (12–)15–19(–21) μm (x̅ = 145 × 17 μm, n = 10), 8-spored, bitunicate, narrowly to broadly clavate, short pedicellate, apically rounded with well-developed ocular chamber. Ascospores 38–43 × 6.5–8.5 μm (x̅ = 40 × 7.5 μm, n = 20), biseriate or overlapping triseriate, slightly curved, hyaline, 1-septate, constricted at the septa, fusiform, guttulate, thin-walled, smooth, lacking a mucilaginous sheath. Asexual morph: Undetermined. (Descriptions from Dong et al. 2020)
Material examined: THAILAND, Songkhla Province, on submerged wood in a stream, 10 May 2018, W. Dong, hat3106-1 (MFLU 18-1718, holotype), ex-type living culture MFLUCC 18-1275; ibid., hat3106-2 (HKAS 105032, isotype), ex-type living culture KUMCC 19-0047.
Notes: Lentistoma aquaticum clusters with L. bipolare with strong bootstrap support. Lentistoma bipolare has crest-like, elongate, laterally compressed neck, while L. aquaticum has ostiolate and short papilla. Lentistoma aquaticum has longer and wider asci ((90–)130–160 × (12–)15–19(–21) μm vs. (82–) 105–140 × 8–15 μm) and longer ascospores (38–43 × 6.5–8.5 μm vs. 20–33 × 5.5–9(–11) μm) than L. bipolare. Additionally, an internal chamber and a narrow sheath drawn out at both ends are described for the ascospores of L. bipolare, but not L. aquaticum. There are 3, 31 and 13 nucleotide differences in LSU, ITS and TEF sequence data, respectively, between L. aquaticum MFLUCC 18-1275 and L. bipolare CBS 115375 (ex-type).m (Notes from Dong et al. 2020)
Freshwater Distribution: Thailand (Dong et al. 2020)