Triblidium daliense C. J. Y. Li, K. W. T. Chethana & Q. Zhao, 2025

Triblidium daliense C. J. Y. Li, K. W. T. Chethana & Q. Zhao sp. nov.

Fig. 2 View Figure 2

Etymology.

The specific epithet refers to Dali City, where the type specimen was collected.

Holotype.

HKAS 128302 View Materials .

Diagnosis.

It is similar to T. sichuanense , but T. daliense has larger asci, wider paraphyses, thicker internal matrix of stroma and the inner layers of the covering and basal stroma consisting of hyaline hyphae.

Description.

Saprobic on the bark of the fallen branches of Fagaceae . Sexual morph: Apothecia 0.9–1.6 mm wide ( x ̄ = 1.2 mm, n = 20) when fresh, 1.1–1.6 mm wide ( x ̄ = 1.2 mm, n = 20), 0.3–0.5 mm high ( x ̄ = 0.4 mm, n = 10) when dried, scattered, superficial, discoid, sessile, erumpent from the bark, initially growing as a cleistohymenial development, the hymenium tightly protected by excipulum when immature, splitting to expose hymenium by usually irregular 6–8 teeth-like lobes in the surface in a humid environment, black (# 4 a 4750) surface with polygonal areolae. Discs flat to slightly raised, circular, orange (# c 4892 d) when fresh, bright orange (# db 9938) when dried. Receptacles rough and black when fresh, sculptured with polygonal areolae or wrinkled on the surface when dried. Covering stroma 54–138 μm thick, comprised of carbonised textura angularis cells and the inner layers of hyaline hyphae. Hymenium 200–236 μm ( x ̄ = 216 μm, n = 10) thick, hyaline to pale brown. Subhymenium 30–50 μm ( x ̄ = 39 μm, n = 15) thick, comprised of hyaline, textura angularis cells, 3.3–7.9 μm ( x ̄ = 5.3 μm, n = 40) in diam. Internal matrix of stroma 55–215 μm ( x ̄ = 123 μm, n = 40) thick, well-developed, comprised of hyaline, textura intricata hyphae, 1.6–2.9 μm ( x ̄ = 2.2 μm, n = 40) in diam., non-gelatinous. Basal stroma 60–95 μm ( x ̄ = 74 μm, n = 40) thick, well-developed, the outer layers comprised of carbonised, very dark brown to black, textura angularis cells, 4.3–10.1 μm ( x ̄ = 6.7 μm, n = 40) in diam., the inner layers comprised of highly melanised hyaline hyphae, 2.9–5.5 μm ( x ̄ = 3.8 μm, n = 40) in diam. Paraphyses 270–330 × 2.1–3.3 μm ( x ̄ = 290 × 2.7 μm, n = 50) wide, hyaline with golden oil drops, filiform, apically irregular-curved and occasionally branched, aseptate. Asci ripening sequentially, 235–292 × 23–28 μm ( x ̄ = 257 × 24 μm, n = 25), unitunicate, 8 - spored, clavate, apically rounded without an amyloid reaction in Melzer’s reagent, tapering to a fragile pleurorhynchous subtruncate base, croziers absent. Ascospores 23.4–35.5 × 11.8–16.5 μm ( x ̄ = 26.7 × 13.4 μm, n = 55, Q = 1.6–2.2, Qm = 2.0 ± 0.1), overlapping uniseriate, ellipsoidal and muriform, hyaline, smooth, slightly curved, eight transverse septa and one or two longitudinal and oblique septa, without a gelatinous sheath. Asexual morph: Undetermined.

Material examined.

China • Yunnan Province, Dali City, Eryuan County, Ma’an Mountain , altitude 2,600 m, on the bark of the fallen branches of Fagaceae , 26 July 2021, Cuijinyi Li, LCJY-209 ( HKAS 128302 View Materials , holotype) ; • ibid., Cuijinyi Li, LCJY-209-2 ( HKAS 145635 View Materials , isotype) .

Notes.

Our collection was placed sister to T. hubeiense , with the Maximum Likelihood bootstrap support of 79.9 % in the SH-aLRT test, 80 % in the UFB method and a Bayesian posterior probability of 0.9 (Fig. 1 View Figure 1 ). Triblidium daliense can be distinguished from T. hubeiense by its smaller apothecia, thinner covering stroma (54–138 μm vs. 270–300 μm), thinner basal stroma (60–95 μm vs. 65–160 μm), carbonised angular cells at the outer layer, wider paraphyses (2.1–3.3 μm vs. ca. 1 μm) with branched tips and larger asci (235–292 × 23–28 μm vs. 160–200 × 15–24 μm) in contrast to the melanised hyphae of the latter species at the outer layers ( Lv et al. 2019). The most morphologically similar species to our species is T. sichuanense , which is distinguished by the presence of angular cells in the inner layers of the covering stroma and basal stroma, a thinner internal matrix of the stroma (50–80 μm vs. 55–215 μm), thinner paraphyses (1 μm vs. 2.1–3.3 μm) and smaller asci (120–220 × 12–20 μm vs. 235–292 × 23–28 μm) ( Guo et al. 2024). Based on the molecular analyses, the ITS sequence of T. daliense exhibited a 3.3 % difference with no gaps (16 / 485) to T. yunnanense (isolate: HOU 1822 B ), while the LSU sequence showed a 2.9 % difference with six gaps (26 / 898) to T. yunnanense (isolate: HOU 875 A ) and the mtSSU sequence displayed a 0.72 % difference with no gaps (6 / 830) to T. hubeiense (isolate: HOU 1350 A ).