Saprodesmium dematiosporum W. Dong, Doilom and K.D. Hyde sp. nov. (Figure 5)
MycoBank number: MB 558197; Index Fungorum number: IF 558197; Facesoffungi number: FoF 09874;
Etymology: in reference to the dematiaceous conidia
Holotype: HKAS 101710
Saprobic on decaying wood submerged in freshwater. Sexual morph: undetermined. Asexual morph: hyphomycetous. Colonies on natural substrate, effuse, gregarious, punctiform, sporodochial, raised, black. Mycelium partly immersed in natural substrate, consisting of branched, septate, thin-walled, smooth, pale brown to brown hyphae. Conidiophores micronematous, mononematous, vesiculate, consisted of 1–4 subglobose, smooth, hyaline cells (each cell 8.5–12 µm diam.), unbranched, septate, constricted at the septa, smooth, thin-walled. Conidiogenous cells 8–11 µm diam. (x = 9.7 µm, n = 10), holoblastic, monoblastic, integrated, determinate, terminal, subglobose, hyaline, smooth, thin-walled. Conidia 21–36 x 14.5–27 µm (x = 27.5 21.5 µm, n = 70), solitary, acrogenous, obovoid to ellipsoidal, subglobose, clearly muriform, olivaceous when young, becoming quite blackish with age and obscuring the septa, with several subhyaline to pale brown basal cells, smooth, thin-walled. Conidial secession schizolytic.
Culture characteristics: on PDA, colony circular, reaching 50 mm diam. in 30 days at room temperature (25–30 ◦C), surface rough, with dense mycelia, dry, raised from the side view, edge entire; from above, dark gray at the margin, pale gray to white at the
middle; from below, black at the margin, dark olivaceous at the middle; not producing pigmentation in culture.
Material examined: CHINA, Yunnan Province, Pingbian District (22◦59′13” N 103◦40′30” E),
on decaying wood submerged in an unnamed stream originated from Dawei Mountain Nature Reserve, 20 September 2017, W. Dong, WF23A (HKAS 101710, holotype), ex-type living culture KUMCC 18-0059; ibid., MFLU 18-1165, isotype.
Habitat and distribution: stream is nearby Nature Reserve in Southern Yunnan of Yunnan-Kweichow Plateau, shallow and clear, flowing rapidly from the Dawei Mountain, surrounded by angiosperms.
Figure 5. Saprodesmium dematiosporum (HKAS 101710, holotype). (a) sporodochia with a mass of conidia and scattered conidia on natural substrate; (b) conidia and conidiophores; (c) conidia attach on pseudoparenchyma of sporodochia; (d,e) conidia with conidiogenous cells (arrows); (i) conidial surface showing muriform patttern; (j,k) colony on PDA (left-front, right-reverse). Scale bars, (b–e,h) 15 µm; (f,g,i) 10 µm.