Clonostachys rosea  (Link) Schroers, Samuels, Seifert & W. Gams, Mycologia 91: 369 (1999)

Index Fungorum number: IF 461067

Associated with a dicotyledonous plant. Sexual morph: Stromata well-developed, erumpent. Ascomata 170–215 × 160–218 μm (x̅ = 183 × 185 μm, n=10), perithecial, densely crowded in groups, globose to subglobose to oval, not collapsing or sometimes slightly laterally pinched when dry, light orange to yellowish orange, KOH-, not papillate, surface smooth to slightly roughened, but not distinctly warted. Ostiole periphysate. Peridium 25–40 μm wide, wider around the ostiole, two strata: outer region 20–30 μm wide, comprising brownish yellow cells of textura angularis to textura globosa, most cells containing a vacuole; inner region 8–15 wide, composed of flat, hyaline cells of textura angularis. Apical paraphyses present. Asci 50–65 × 6–7.2 μm (x̅ = 54.2 × 6.7 μm, n=15), 8-spored, unitunicate, narrowly clavate, apex flat with somewhat rounded edges, short pedicellate, apical ring J-. Ascospores 9–12 × 3–3.4 μm (x̅ = 10.6 × 3.1 μm, n=20), biseriate above and uniseriate below, hyaline, 1-septate, not constricted at the septum or slightly constricted in mature ascospores, ellipsoidal to oblong ellipsoidal, 4-guttulate, spinulose, without a mucilaginous sheath. Asexual morph: See Schroers et al. (1999).

Culture characteristics – Colonies growing on PDA reached 25 mm in 14 days at 28 °C, surface effused, smooth, margin entire to undulate, aerial mycelium rare, white, reverse yellowish with pale orange center.

Material examined – Thailand, Phayao Province, Chiang Kham District, on twigs of a dicotyledonous plant, R.H. Perera, 11 September 2017, Bion 17 (MFLU 19-0960), living culture MFLUCC 17-2632.

GenBank numbers – ITS: MN597465, LSU: MN597462.

Known distribution (based on molecular data) – Brazil, United States of America (Moreira et al. 2016), Thailand (this study).

Known hosts (based on molecular data) – Fragaria sp., Lilium aurantum (Moreira et al. 2016).

Notes – The new isolate MFLUCC 17-2632 grouped with Clonostachys rosea isolates. A comparison of nucleotides showed one nucleotide difference in the ITS locus of C. rosea isolates CBS 194.57 and CBS 193.94. Our collection resembles C. rosea by having similar ascomatal morphology and asci and ascospore dimensions (Rossman et al. 1999, Schroers 2002).

Clonostachys rosea (MFLU 19-0960, new host record). a Herbarium material. b Ascomata on host. c, d Sections of ascomata. e Section of stroma. f Section of peridium. g Apical paraphyses. h, i Asci. j–n Ascospores. Scale bars: b = 200 μm, c, d = 100 μm, e–i = 20 μm, j–n = 10 μm.