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

Figs 5 , 6 , 7

Etymology.

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

Diagnosis.

It is characterized by having ascomata, are clustered, disc-shaped, or margin irregular disc-shaped, and the outer surface of the apothecium is adorned with brown-orange to brownish-red particles; under scanning electron microscope (SEM) observation, the elliptical ascospores have a smooth surface, with a size of 17.3–21.4 (23.1) × 8.1–10.9 (11.7) μm, and 7 - or 8 - spored asci with a size of 363–388 (425.8) × 9.2–14.1 μm.

Holotype.

China • Guangxi Zhuang Autonomous Region, Guilin City, Huaping National Nature Reserve , 25°63'N, 109°92'E, ca 950 m alt., on buried wood on the ground mixed with evergreen broad-leaved trees and bamboo, 19 July 2024, J. R. Liu (HP 2024071903, IBK, holotype!) (ITS: PQ 691391 ; nrLSU: PQ 682445 ; rpb 2: PV 296007 ; tef 1 - α: PV 296000 ).

Description.

Apothecium clustered, sometimes single, disc-shaped or margin irregular disc-shaped, reaching a diameter of 18–26 mm, with a thickness of 1 mm, subsessile (Fig. 5 a ). Hymenium surface has wart-like protrusions, some of which are adorned with tiny tomentum, dark brown (Fig. 5 b, e ). External surface shares a similar color to the hymenium, being relatively rough and adorned with brownish-orange to brownish-red particles, which are typically confined to the cup margin but occasionally cover the entire outer surface, relatively tough in texture (Fig. 6 c, d ). Odor and taste not special.

External hairs are nearly cylindrical, septate, with a diameter ranging from (5.1) 6.0–7.2 (7.5) μm, slightly curved, and smooth. They originate from the outer cortical layer and appear brown due to epidermal pigmentation, with walls thickened up to 1 μm (Figs 6 f – h , 7 h ). Ectal excipulum consists of a textura angularis, thick-walled cells that are dark brown and measuring 115–135 μm, with slightly thick walls. Medullary excipulum composed of a textura intricata, measuring 480–550 μm in thickness, subhyaline to yellowish white, and consisting of hyphae 4.1–7.0 μm in diameter (Figs 6 c , 7 g ). Subhymenium is a dense textura intricata of closely septate hyphae, olive-colored (2 F 5), with a thickness of (46.6) 62.2–110 μm. Hymenium (329.5) 363.5–422.8 μm thick. Asci cylindrical, suboperculate, 8 - spored (occasionally with 7 spores), thick-walled, inamyloid, measuring 363–388 (425.8) × 9.2–14.1 μm (Figs 6 i, j , 7 a ). Paraphyses 1.9–3.4 μm in diameter, filiform, septate, branched, and slightly enlarged or narrowed near the apex (Figs 6 l – m , 7 f ). Ascospores uniseriate, ellipsoid, equilateral, hyaline, smooth, usually contain 1–2 guttules and measuring [37 / 6 / 2] 17.3–21.4 (23.1) × 8.1–10.9 (11.7) μm (Figs 6 d, e , 7 b ), with Q values = (1.5) 1.7–2.2 (2.4) and an average Q value of 2. Crystals few to abundant, present among the hairs and in the outer surface of the ectal excipulum. Hymenial hairs cylindrical, comparable in length with paraphyses, non-septate but with a single septum in the basal part, 2.2–3.3 μm wide, concolor with paraphyses due to the homogeneous pigments, tips rounded, straight to slightly curved, unbranched (Figs 6 k , 7 e ). Anamorph unknown.

Habitat.

Half-buried in the litter layer in moist forest mixed with evergreen broad-leaved trees and bamboo.

Geographic distribution.

By now, only known from Guangxi Zhuang Autonomous Region, China.

Other material examined.

China • Guangxi Zhuang Autonomous Region, Guilin City, Huaping National Nature Reserve , 25°63'N, 119°92'E, ca 850 m alt., 20 July 2024, J. R. Liu, HP 2024072014 (ITS: PQ 691390 , nrLSU: PQ 682444 ) .

Notes.

P. huapingensis and P. melastoma share macroscopic characteristics of apothecial external surfaces and margins covered with orange granules. However, upon comparing their microscopic features, it becomes evident that the asci of P. huapingensis [asci: 363–388 (425.8) × 9.2–14.1 μm] and its ascospores [17.3–21.4 (23.1) × 8.1–10.9 (11.7) μm] are smaller than those of P. melastoma (asci: 400–450 × 12–15 μm; ascospores: 21.8–25 × 10–12.4 μm) ( Agnello and Carbone 2012; Zeng et al. 2021). This difference serves as a distinguishing factor between the two species. Furthermore, with the distinctive feature of its apothecial external surface and margin being covered with orange granules, P. huapingensis can be clearly differentiated from other species within the genus Plectania .

P. huapingensis shares morphological similarities with Korfiella karnika D. C. Pant & V. P. Tewari in both macroscopic and microscopic characteristics. However, molecular sequence data from K. karnika and its allied species remain unavailable. Given that P. huapingensis aligns with the genus Plectania in molecular phylogeny and micromorphological features, P. huapingensis exhibits morphological distinctions from K. karnika , specifically the presence of hymenial hairs (absent in K. karnika ) and mature asci containing 7–8 ascospores (versus 2–4 ascospores per ascus in K. karnika ), and it should be classified as a member of Plectania s. lat clearly from phylogenetic evidence ( Pant and Tewari 1970).

Figures

Figure 5. Ascocarps of Plectania huapingensis (photos by J. R. Liu). a, d. Habitat of specimen HP 2024071903 (IBK!), found on senescing or dead bamboo rhizomes; b, c. Habitat of specimen HP 2024072014 (IBK!), growing on dead woody branches on the ground or dead bamboo rhizomes; e. Vertical section showing dark violet thin flesh; f. Details of the external surface. Scale bars: 10 mm (a – e); 1 mm (f).

Figure 6. Features of Plectania huapingensis (photos by J. R. Liu, from HP 2024071903, IBK!). a. Section of apothecium; b. External hairs; c. Medullary excipulum; d, e. Ascospores; f – h. External hairs; i, j. Asci; k. Hymenial hair; l, m. Paraphyses. Scale bars: 50 μm (a); 10 μm (b, c, i – m); 5 μm (d – h).

Figure 7. Microscopic structures of Plectania huapingensis (drawings by J. R. Liu). a, d. Asci; b. Ascospores; c. Apex of asci; e. Hymenial hair; f. Paraphyses; g. Medullary excipulum; h. External hairs. Scale bars: 10 μm (a, c, d); 5 μm (b, e – h).