Ceratosphaeria aquatica Z.L. Luo, K.D. Hyde & H.Y. Su, in Luo et al., Fungal Diversity: 10.1007/s13225-019-00438-1,
Index Fungorum number: IF555644
Holotype – MFLU 18–2323
Saprobic on decaying wood submerged in freshwater habitat. Sexual morph: Ascomata 269–361 µm high, 196–284 µm diam., deeply immersed with neck erumpent through host surface, globose to subglobose, brown to yellow brown, occurring solitary. Neck long, surface smooth, at times with yellow crystals. Peridium 29–43 µm thick, composed of an inner layer of flattened hyaline cells, a middle layer of small, polygonal to irregular, pale brown cells, an outer layer of irregular, yellow brown, pseudoparenchymatic cells. Paraphyses 4–7 µm wide, longer than asci, tapering above. Asci 86–124 × 13–21 µm (x̅ = 105 × 17 µm, n = 30), 8-spored, unitunicate, cylindrical to broadly fusiform, with a narrow apical ring. Ascospores 89–95 × 4–7 lm (x̅ = 92 × 5.5 µm, n = 30), filiform, mostly 3-septate, guttulate, hyaline, smooth-walled. Asexual morph: Undetermined (adapted from Luo et al. 2019).
GenBank numbers: LSU: MK835812, ITS: MK828612, tef1: MN194065, rpb2: MN156509
Notes: Ceratosphaeria aquatica resembles C. phialidica in having deeply immersed ascomata and filiform, hyaline ascospores (Huhndorf et al. 2008). However, Ceratosphaeria aquatica differs from C. phialidica in having broader cylindrical asci (13–21 vs. 5.5–6.5 µm) and guttulate, septate, larger ascospores (89–95 × 4–7 vs. 65–85 × 1.3–1.7 µm). Ceratosphaeria aquatica also shares similar morphological characters with C. lignicola in terms of filiform, guttulate, hyaline ascospores. However, C. aquatica differs from C. lignicola in having 3-septate, wider ascospores (4–7 vs. 3.5–4.5 µm). Phylogenetic analysis has supported C. aquatica as a distinct species (Luo et al. 2019).
Ceratosphaeria aquatica (Material examined – CHINA, Yunnan Province, saprobic on decaying wood submerged in a freshwater river, April 2015, Z.L. Luo, S-639, MFLU 18-2323). a Appearance of necks on substrate. b, c Section through ascomata. d Paraphyses. e Structure of peridium. f, g Asci. h-l Ascospores. Scale bars: b, c = 200 μm, d, e, h-l = 20 μm, f, g = 50 μm (image from Hyde et al. 2020).