Pseudoastrosphaeriella aquatica W. Dong, H. Zhang & K.D. Hyde
Index Fungorum number: IF557932, Facesoffungi number: FoF09275
Holotype: MFLU 18-0996
Etymology: referring to aquatic habitat of this fungus
Saprobic on decaying wood submerged in freshwater. Sexual morph: Ascostromata 250–350 μm high, 280–320 μm diam., black, scattered or gregarious, immersed with neck erumpent through host tissue, becoming raised, subglobose, coriaceous, ostiolate. Neck 450–500 μm high, 100–110 μm diam., black, central, cylindrical, oblique, brittle, thickwalled, comprising some layers of blackened cells, carbonaceous. Peridium 15–25 μm thick, of unequal thickness, composed of thin-walled, hyaline to brown, compressed cells of textura angularis or textura prismatica, outer layers comprising host cells and fungal tissue. Pseudoparaphyses 1 μm diam., numerous, trabeculate, filiform, hyaline, branching and anastomosing, embedded in a gelatinous matrix. Asci 145–260 × 19–25 μm (x̄ = 213 × 22 μm, n = 15), 8-spored, bitunicate, distinctly clavate, or cylindrical, with elongate pedicel, up to 115 μm long, with indistinct ocular chamber. Ascospores 40–48 × 8–10.5 μm (x̄ = 44.5 × 9.5 μm, n = 30), overlapping uni-seriate or uni-seriate at the base and bi- to tri-seriate near the apex, fusiform, with acute or rounded ends, brown, 3-septate, constricted at the septa, swollen above central septum, guttulate, thin-walled, smooth. Asexual morph: Undetermined. (Description from Dong et al. 2020)
Material examined: THAILAND, Chiang Mai Province, on submerged wood in a stream, 9 February 2018, X.D. Yu, Y18 (MFLU 18-0996, holotype), ex-type living culture MFLUCC 18-0984; Phayao Province, on submerged wood, 23 February 2018, X.D. Yu, Y27 (MFLU 18-1005), living culture MFLUCC 18-0991; Chiang Rai Province, on submerged wood, 10 April 2018, X.D. Yu, Y41 (MFLU 18-1016), living culture KUMCC 19-0096.
Notes: Pseudoastrosphaeriella aquatica is similar to P. papillata in having black ascomata with long necks and similar in shape and overlapping size of ascospores, but the smooth-walled, 3-septate ascospores of the former differs from the rough-walled, mostly 1-septate ascospores with small, pad-like appendages of the latter (Hyde and Frohlich 1998; Phookamsak et al. 2015). (Notes from Dong et al. 2020)
Freshwater distribution: Thailand (Dong et al. 2020)