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Family: HypocreaceaeGenus: Trichoderma
Anamorph: mainly in association with young stromata, effuse, powdery, dark green. Conidiomata absent. Conidiophores formed on a thick-walled stipe to 10 μm diam. at the base. Further branching asymmetric, primary branches (bases of main axes) 7–9 μm diam., thick-walled, quickly narrower upwards, then mostly 4–5 μm diam., terminal branches and origins of conidiogenous cells 2.5–4 (–4.5) μm diam. Main axes straight or sinuous, mostly ill-defined, terminating in short (ca 50 μm) fertile conidiophores, often with few short paired branches at right angles or slightly inclined upward, and solitary conidiogenous cells at upper levels; or terminating in straight, initially sterile elongations projecting 100–200 μm, becoming fertile. Conidiogenous cells (4–) 5–15 (–23) × (2.5–) 3–4 (–4.5) μm, lageniform and inequilateral or ampulliform and symmetric or with a bent neck, solitary or in whorls of 2–3 (–5), divergent but often steeply inclined, proliferating percurrently. Conidia formed in minute wet or dry heads <30 μm diam., (3.5–) 4–6 (–8.5) × (2.5–) 3–3.5 (–4.5) μm, l/w ratio 1.2–1.8 (–2.4), ellipsoidal, less commonly cylindrical or ovoid, green, smooth, multiguttulate or with few large guttules, scar indistinct.
Teleomorph: stromata when fresh (0.7–) 1–3 (–4) mm diam, 0.5–1 (–1.5) mm thick, pulvinate or lenticular, less commonly turbinate, the basal part centrally attached, often like a broad stipe, pale orange. Surface smooth, with numerous fine but distinct ostiolar dots, white to pale yellowish when young, then yellowish, the ostiolar dots at first pale brownish, becoming olive to dark green upon maturation; resulting colour olive, greyish yellow or shades of green, dark green to black due to extruded ascospores when old, sometimes finally (reddish) brown. Perithecia (135–) 165–210 (–235) × (90–) 115–170 (–190) μm, flask-shaped or globose. Ostiolar necks (47–) 55–66 (–70) μm long, plane or projecting to 20 (–30) μm. Peridium (5–) 10–17 (–20) μm thick at the base and sides, yellow, orange-yellow in KOH. Interascal tissue absent. Asci (90–) 100–120 (–135) × (5–) 5.5–6.5 (–7.5) μm, stipe (6–) 10–23 (–36) μm long. Ascospores (yellowish) green, verruculose; cells dimorphic. Distal cell (4–) 4.5–5.5 (–6.5) × (3.5–) 4.5–5 (–5.5) μm, l/w ratio (0.9–) 1.0–1.2 (–1.5), (sub-)globose or wedge-shaped. Proximal cell (4.5–) 5–6.5 (–8) × (3.2–) 3.7–4.3 (–5) μm, l/w ratio (1.0–) 1.2–1.7 (–2.2), cylindrical or wedge-shaped, less commonly subglobose, often slightly longer towards the ascus base.