Plectania damingshanensis G. F. Mou & J. R. Liu, 2025

Liu, Jin Rong, Li, Deng, Chen, Si Ang, Zhang, Yan Cheng, Mou, Guang Fu, Liu, Yan, Zhou, Guang Rong, Tan, Zhou Rong & Zhang, Jian Hua, 2025, Species diversity and systematic taxonomy of Sarcosomataceae (Ascomycota, Pezizales), with an emphasis on subtropical regions of China, MycoKeys 121, pp. 21-65 : 21-65

Plectania damingshanensis G. F. Mou & J. R. Liu sp. nov.

Figs 2 , 3 , 4

Etymology.

The specific epithet refers to the type locality, Damingshan National Nature Reserve, in China.

Diagnosis.

It is characterized by the cupulate ascomata, the surface of hymenium with brownish orange to light brown color, external surface and stipe (when present) densely covered with grey tomentum and tree-like ridges, the elliptical ascospore is warty under SEM, (21.7) 22.5–32.0 (34.6) × (11.0) 12.1–14.7 (16.5) μm.

Holotype.

China • Guangxi Zhuang Autonomous Region, Nanning City, Damingshan National Nature Reserve , 23°49'N, 108°43'E, ca 1230 m alt., on rotten fallen sticks or wood surrounded by moss in the evergreen broad-leaved forest, 19 Feb. 2024, Guang R. Zhou (DMS 2024022001, IBK, holotype!) (ITS: PP 864720 ; nrLSU: PP 859016 ; rpb 1: PV 247118 ).

Description.

Apothecium cupulate, up to 19–27 mm in diameter, 20–30 mm high, subsessile to stipitate (Fig. 2 a, b ). Hymenium surface glabrous, without ornamentation or wrinkled, brownish orange (6 C 6) to light brown (6 D 7), brown-dark, brown (6 E 8–6 F 8) after drying, margin with light brown (6 D 5) tomentum. External surface reddish brown-dark brown (7 D 8–7 F 8), brownish grey (8 F 2) after drying. Stipe (when present) up to 2–20 mm long, 7.5–9 mm in width, densely covered with grey (8 D 1–8 F 1) tomentum and tree-like ridges extending all the way to the margin of the cup (Fig. 2 b, d ). Flesh solid, wet, gelatinous at a high level, semitransparent, slight grey (8 B 1). Odor and taste not special.

External hairs curved and flexuous, septate, glabrous, brown (6 E 7) with an olive tint (1 E 8), 5–8.5 μm in diameter, with obtuse end (Fig. 3 g, h ). Ectal excipulum of textura angularis made up of thick-walled cells, brownish to dark brown, 13–91 μm thick (Fig. 3 g ), near the margin arranged in separable moniliform hair-like cells, 6.2–10.6 μm diam (Figs 3 f , 4 g ). Medullary excipulum of loose textura intricata immersed in a highly gelatinous matrix, approximately 380–1000 μm, subhyaline to yellowish white (2 A 2), composed of 2–4.2 μm broad hyphae (Figs 3 c , 4 f ). Subhymenium of a dense textura intricata of closely septate hyphae, olive brown (4 D 7–4 D 6), 50–80 μm thick. Asci cylindrical, suboperculate, 8 - spored, rarely with 7 spores, thick-walled, inamyloid, 322–401 (426) × 11.0–15.6 (Fig. 3 j – m , 4 a ). Paraphyses 1.5–3 μm diam, filiform, septate, branched, slightly enlarged or narrowed near apex (Figs 3 d , 4 d ). Ascospores uniseriate, ellipsoid, equilateral, hyaline, very finely warty under light microscope (× 1000, Fig. 3 i ), verrucose to vermicular under scanning electron microscope (Fig. 16 b ), with 1–2 guttules, [40 / 5 / 2] (21.7) 22.5–32.0 (34.6) × (11.0) 12.1–14.7 (16.5) μm, Q = (1.7) 1.8–2.3 (2.6), Q av = 2.0. Hymenial hairs cylindrical, comparable in length to the paraphyses, non-septate, 2.1–4.4 μm in diameter, concolor with paraphyses due to the homogeneous pigments, agglutinating or intermingle with paraphyses to bundles, tips rounded to slightly subcapitate, straight or curved, unbranched (Figs 3 e , 4 c ). Anamorph unknown.

Habitat.

Growing in scattered to gregarious groups on moss-covered decaying wood in broadleaf forests.

Geographic distribution.

So far, only known from Guangxi Zhuang Autonomous Region, China.

Other specimens examined.

China • Damingshan National Nature Reserve , 23°49'N, 108°43'E, alt. 1225 m, on wood surrounded by moss in the evergreen broad-leaved forest, 19 Feb. 2024, Guang R. Zhou, DMS 2024022002 ( IBK!) (ITS: PP 864721 ; nrLSU: PP 859017 ; tef 1 - α: PV 295998 ); DMS 2024022003 ( IBK!) (ITS: PP 864722 ; nrLSU: PP 859018 ) . Mao’ershan National Nature Reserve , 25°88'N, 110°37'E, ca 720 m alt., on rotten fallen sticks, 6 April 2024, Yan C. Zhang, MES 024040606 ( IBK!) (ITS: PQ 691392 ; nrLSU: PQ 682446 ; rpb 1: PV 247119 ; tef 1 - α: PV 295999 ) .

Notes.

In the phylogenetic tree (Fig. 1 ), P. damingshanensis and P. lutea were grouped together with strong support (MLB = 100 %, BPP = 1). Both species share ellipsoid and verrucose ascospores with similar dimensions: P. damingshanensis measures (21.7) 22.5–32.0 (34.6) × (11.0) 12.1–14.7 (16.5) μm, while P. lutea measures (24.5) 27.0–30.0 (32.0) × (12.2) 13.0–15.0 (16.0) μm ( Mou and Bau 2021). However, the external surface of P. damingshanensis is densely covered with grey tomentum and tree-like ridges that extend to the margin, and its apothecium is larger with a longer and thicker stipe. While the external surface of P. lutea has fewer brown hairs and irregular, vascular ridge-like protrusions, with ascomata measuring only 11.0–18.0 mm in diameter. P. sichuanensis is distinguished from P. damingshanensis by its hymenium, which is ochre in color and lacks a noticeable covering of black hairs, and its smaller, smooth ascospores (22–26 × 11–13 μm) ( Zeng et al. 2021).

From a microscopic perspective, the ascospores of P. damingshanensis , as well as those of P. zugazae Calonge & Alb. García , P. melastoma described in older mycological literature, and P. harnischii M. Carbone, Agnello, A. D. Parker & P. Alvarado , are all elliptical and verrucose ( Carbone et al. 2015 a, 2021). However, there are significant differences in ascospore size among the four species, P. damingshanensis having larger ascospores [(21.7) 22.5–32.0 (34.6) × (11.0) 12.1–14.7 (16.5) μm], while ascospores of P. zugazae [18–22 × 12–14 μm] and P. melastoma [21.8–25 × 10–12.4 μm] are notably smaller. As for P. harnischii , it exhibits the narrower ascospores with a size of 20.2–24.8 × 8.1–11.2 µm.

Plectania damingshanensis exhibits numerous similarities to species within the Galiella genus, featuring brightly colored ascocarps, highly gelatinized fleshy tissue, and ascospore surfaces adorned with wart-like ornamentation. However, on the phylogenetic tree, P. damingshanensis does not cluster with G. amurensis and G. rufa . Additionally, it is noteworthy that the ascospores of G. amurensis lack oil droplets, and its asci (measuring 400–450 × 12–17 μm) and ascospores [measuring (26) 28–37.5 (40) × 11.5–17.5 (18) μm] are larger compared to those of P. damingshanensis . Conversely, the asci (measuring 270 × 12 μm) and ascospores [measuring (17) 18–21 (23) × 8–10 μm] of G. rufa are smaller ( Carbone et al. 2015 b).

Figures

Figure 1. Phylogenetic tree of Sarcosomataceae inferred from the dataset with the aligned ITS + nrLSU + rpb 1 + rpb 2 + tef 1 - α contig. Nodes are separated by ‘ - / - ’ (MLB / BPP) and indicated if bootstrap support values for ML ≥ 50 % and / or posterior probability for BI ≥ 0.90. Specimens of new taxa of the current study are highlighted in red. The letters HT, ET, IT, and NT, and the country highlighted in blue after the specimens stand for holotype, epitype, isotype, neotype, and the original country, respectively. Icons depicting the shape and ornamentation of spores and the presence and position of a gelatinous sheath are indicated after the specimens and correspond to abbreviations. VE indicates verrucose or vermicular ellipsoid spores without a gelatinous sheath. VES indicates verrucose or vermicular ellipsoid spores with a gelatinous sheath. SA indicates a smooth allantoid spore without a gelatinous sheath. GE indicates grooved ellipsoid spores without a gelatinous sheath. SE indicates smooth ellipsoid spores without a gelatinous sheath. SES indicates smooth ellipsoid spores with a gelatinous sheath. SG indicates smooth, globose to subglobose spores without a gelatinous sheath. SGC indicates smooth globose to subglobose spores with a centrally arranged gelatinous sheath. SGE indicates smooth globose to subglobose spores with an eccentrically arranged gelatinous sheath.

Figure 2. Ascocarps of Plectania damingshanensis. Photos by Guang R. Zhou and G. F. Mou. Scale bars: 10 mm (a – d).

Figure 3. Features of Plectania damingshanensis. (photos by J. R. Liu, from holotype: DMS 2024022001, IBK!). a. Section of apothecium; b. Hymenium; c. Medullary excipulum; d. Paraphyses and a hymenial hair; e. Hymenial hair; f. Moniliform hair-like cells; g, h. External hairs; i. Ascospores; j – m, o. Asci; n. Apex of asci. Scale bars: 100 μm (a); 20 μm (b, j – m); 10 μm (c – i, n – o). c, e, m in 1 % Congo Red solution.

Figure 4. Microscopic structures of Plectania damingshanensis (drawings by J. R. Liu, from holotype DMS 2024022001, IBK!). a. b. Asci; c. Hymenial hair; d. Paraphyses; e. Ascospores; f. Medullary excipulum; g. External hairs and ectal excipulum; h. Moniliform hair-like cells. Scale bars: 20 μm (a, b); 10 μm (c, d, f – h); 5 μm (e).

Figure 16. Scanning electron micrograph of basidiospores of the four new species of Sarcosomataceae from China (photos by J. R. Liu). a. Plectania huapingensis; b. Plectania damingshanensis; c. Pseudoplectania aureonigrescens; d. Urnula auricularioides. Scale bars: 2 µm (a – d).