Trichoderma neopyramidale X. F. Liu, Karun., Tibpromma & K. D. Hyde 2026, sp. nov.

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Trichoderma neopyramidale X. F. Liu, Karun., Tibpromma & K. D. Hyde sp. nov. Fig. 12 Etymology. Named after its phylogenetically closeness to Trichoderma pseudopyramidale and morphological similarity to Trichoderma pyramidale. Holotype. GMB -W 1534. Description. Associated with rock surface in the cave environment. Asexual morph on PDA: Vegetative hyphae 2–8 μm wide, septate, branched, hyaline, smooth-walled. Conidiophores pyramidal with verticillate, comprising a recognizable main axis, pairs or solitary branches, longer branches near the base, and short branches or solitary phialides arising near the tip. Phialides 5–15 × 2–4 µm (x ̄ = 8.82 × 2.79 μm, n = 60), ampulliform to lageniform, generally formed on terminal branches in divergent whorls of 1–3. Supporting cells 5–13 × 2–4 µm (x ̄ = 7.91 × 2.63 μm, n = 50). Conidia 2–5 × 2–4 µm (x ̄ = 3.44 × 2.95 μm, n = 90), subglobose to globose, or ovoid, green, smooth-walled. Chlamydospores 4–6 × 3–5 µm (x ̄ = 5.14 × 4.34 μm, n = 10), single or in clusters, terminal and intercalary, variable in shape, mostly subglobose to globose, thick-walled, hyaline, granulate. Sexual morph: Undetermined. Culture characteristics. Colonies on PDA attaining 60 mm after 7 days at room temperature (25 ± 2 ° C), white, gray to green, sparse aerial mycelium on the surface, regularly circular, green conidiation occurs over time, reverse is green in the middle and white on the edges. Material examined. CHINA • Yunnan Province, Dehong Dai and Jingpo Autonomous Prefecture, Mang City, Mengga Town, Sanxian Cave, rock surface, 24.232220°N, 98.426103°E, elev. ca 1528.89 m, 23 April 2024, Xiangfu Liu and Xuemei Chen, MS 32 C (GMB -W 1534, holotype), ex-type GMBCC 2303, ibid., MS 32 D (GMB -W 1535, isotype), ex-isotype GZCC 25-0729. Notes. Phylogenetic analyses revealed that Trichoderma neopyramidale (GMBCC 2303 (ex-type), and GZCC 25-0729) forms a distinct lineage and is closely related to T. pseudopyramidale and T. hydei X. F. Liu, Karun. & Tibpromma (Fig. 7). Trichoderma neopyramidale (GMBCC 2303, ex-type) and T. pseudopyramidale (GMBCC 2300, ex-type) revealed 2.52 % (21 / 833 bp, 2 gaps) base pair differences in rpb 2, and 6.04 % (35 / 579 bp, without gaps) differences in tef 1 - α. Trichoderma neopyramidale (GMBCC 2303, ex-type) and T. hydei (GMBCC 1136, ex-type) revealed 1.77 % (16 / 904 bp, without gap) base pair differences in rpb 2, and 2.92 % (23 / 787 bp, without gap) differences in tef 1 - α. Morphologically, T. neopyramidale differs from T. pseudopyramidale by the latter having smaller phialides (5–15 × 2–4 µm vs. 5.3–8.6 × 2.2–2.9 µm), smaller supporting cells (5–13 × 2–4 µm vs. 3.3–7.1 × 1.9–2.8 µm), and larger conidia (2–5 × 2–4 µm vs. 2.1–2.9 × 2.3–2.9 µm) (Rodríguez et al. 2021). Trichoderma neopyramidale differs from T. hydei by the latter having white, gray to green culture, more (1–3 whorls vs. 2–3 whorls) and slightly longer (5–15 × 2–4 µm vs. 6–17 × 2–4 µm) phialides, bigger supporting cells (5–13 × 2–4 µm vs. 6–15 × 2–4 µm), and smaller conidia (2–5 × 2–4 µm vs. 2–4 × 2–3 µm) (Hongsanan et al. 2025). Trichoderma neopyramidale and T. pyramidale share several characteristics in common, such as pyramidal conidiophores with 2-4 whorls phialides. Trichoderma pyramidale has smalller phialides ((4.0 -) 5.5-11.5 (- 17.5) × (2.5 -) 2.8-3.7 (- 4.5)) and conidia ((2.8 -) 3.2 - 4.0 (- 4.7) × (2.5 -) 3.0-3.5 (- 4.0) μm), and uncommon chlamydospores (Chaverri et al. 2015). In addition, the PHI test results (Fig. 6 B 4) revealed no significant recombination relationships between T. neopyramidale and its phylogenetically related taxa within the dataset. Based on phylogenetic analyses and morphological characteristics, Trichoderma neopyramidale is introduced as a new species.

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