Botryosphaeria dothidea (Moug.) Ces. & De Not., Comm. Soc. crittog. Ital. 1(fasc. 4): 212 (1863).
See Species fungorum for synonyms.

Index Fungorum number: IF 183247; MycoBank number: MB 183247; Facesoffungi number: FoF 03512; Fig. 1

Saprobic on submerged wood of freshwater. Sexual morph: Ascomata 300–500 μm diam., black, circular or subglobose to globose, scattered, gregarious, uni- to multiloculate, immersed to erumpent on host tissue, with visible black dots or papilla. Ostiole circular, central, papillate. Peridium composed of two-layered locules, outer layer composed of dark brown or brown thick-walled cells of textura angularis, inner layer composed of hyaline thin-walled cells of textura angularis lining the locule. Pseudoparaphyses 2–4 μm wide, hyphae-like, septate. Asci 96–144×18–25 μm (x̄ =116×23 μm, n=10), 8-spored, bitunicate, fissitunicate, cylindrical to clavate, short pedicellatea, pically rounded with an ocular chamber. Ascospores 21–32 × 10–14 μm ( x̄ =26.3 × 11.7 μm, n=40), biseriate, hyaline, aseptate, fusoid to ovoid, sometimes with tapered ends, spindleshaped, thin-walled, smooth with granular contents. Asexual morph: Not observed.

Cultural characteristics – Ascospore germinating on PDA within 24 h. Colonies on PDA fast-growing, reaching 7–8 cm diameter in 50 days at 20–25 °C, with dense, hairy, black mycelium on the surface, reverse black.

Material examined – China, Yunnan Province, a small river of Puzhehei wetland, on dead submerged decaying wood of unidentified plants, 23 June 2019, Hao Yang, p27 (IFRD500–008), living culture KUMCC 20–0186.

Known hosts and distribution – broad range of hosts and wide geohraphical distribution (Farr and Rossman 2022)

GenBank numbers – MT559116 (LSU), MT559099 (ITS)

Notes – Botryosphaeria dothidea is the type species of the genus, and was reported extensively from all around the world (Fries 1823; Arx and Müller 1954). It was epitypified by Slippers et al. (2004) based on morphology and phylogeny. This taxon was collected from southwest China and its ITS sequence data of our isolate are 100% identical to the verified sequences of B. dothidea (MH992666 and MH973592). Based on morphology and phylogenetic analyses (Fig. 2), we identify the strain as B. dothidea. It is a new geographic record from China and a new habitat record from freshwater.

Figure 1 – Botryosphaeria dothidea (IFRD500–008, new geographic and habitat record) a, b Appearance of ascomata on host substrate. c Section of ascomata. d Peridium. e Pseudoparaphyses and asci. f–i Asci. j–l Ascospores. m–n Colony on PDA (m from front, n from reverse). Scale bars: a=500 μm, b=200 μm, c, e=100 μm, d=30 μm, f–i=20 μm, j–l=10 μm

Figure 2 – Phylogram generated from maximum likelihood analysis based on combined ITS, and tef1 sequence data for the Botryosphaeria. The combined dataset consists of 23 taxa from Botryosphaeria with our strain. The tree is rooted with Macrophomina phaseolina (CBS 227.33). The topology of the maximum likelihood analysis is similar to Bayesian analysis. Bootstrap support value for ML≥60% and BYPP≥0.90 are given above the branches. The ex-type strains are in bold. The newly generated sequence is in red