Tatraea yunnanensis C.J.Y. Li & Q. Zhao, 2024

Li, Cui-Jin-Yi, Thilini Chethana, Kandawatte Wedaralalage, Eungwanichayapant, Prapassorn Damrongkool, Zhou, De-Qun & Zhao, Qi, 2024, Additional four species of Tatraea (Leotiomycetes, Helotiales) in Yunnan Province, China, MycoKeys 102, pp. 127-154 : 127

Tatraea yunnanensis C.J.Y. Li & Q. Zhao sp. nov.

Fig. 7

Etymology.

The specific epithet refers to the locality from where the type species was collected.

Holotype.

HKAS 128273.

Description.

Saprobic on the decayed wood. Sexual morph: Apothecia 3.8-5.0 mm wide × 2.5-4.1 mm high (x̄ = 4.8 ± 0.8 × 3.7 ± 0.8 mm, n = 10) when dry, scattered, superficial when fresh, short stipitate, glabrous. Disc circular, flat or slightly concave when fresh, yellowish white (4A2) to orange white (5A2), edge strongly curl inward towards the disc when dry, pastel green (29A4-30A4) to light green (29A5), dull green (29E4) near the edge. Margins concolorous to the disc when fresh, white or concolorous to the disc when dry. Receptacle rough and pale greyish orange (5B3) with loose, finely yellowish brown (5E8) pustules when fresh, rough and light brown (5E4) with finely dark pustules and irregular patches when dry, center of vertical section appears white powder, outwardly yellowish waxy materials. Stipe 0.5 mm wide × 1.1 mm long, concolorous to the receptacle, dense finely granular pustules. Hymenium 173-213 μm (x̄ = 192 ± 10 μm, n = 20) thick, hyaline. Subhymenium 51.5-68.5 μm (x̄ = 60.5 ± 5.0 μm, n = 27) thick, slightly indistinguishable from the medullary excipulum, comprised of dense and unordered brown (5D4) hyphae of textura intricata, hyphae 2.2-5.4 μm (x̄ = 3.9 ± 0.9 μm, n = 20) diam., with excipulum at the margin. Medullary excipulum 435-560 μm (x̄ = 518 ± 48 μm, n = 10) thick, well-developed, comprised of thin-walled, septate, branched, hyaline and lose hyphae of textura intricata in the center, partially cells of hyphae becoming swollen, hyphae 3.6-7.8(-8.9) μm (x̄ = 5.3 ± 0.9 μm, n = 77) diam., becoming well-organized, parallel near to the ectal excipulum, hyphae narrower, non-gelatinous. Ectal excipulum of the inner layers usually comprised of 3-5 layers of textura angularis to textura prismatica cells oriented vertically to the receptacle, brown to hyaline from the outside to inside, 37-65 μm (x̄ = 49.5 ± 8.8 μm, n = 70) thick, cells 8.4-16.5 μm (x̄ = 13.0 ± 1.1 μm, n = 50) diam., wall moderately thick 0.56-0.9 μm (x̄ = 0.72 ± 0.11 μm, n = 84) thick; the outer layers uneven dense proliferous 2-10 layers of textura angularis to textura prismatica cells, 20-74 μm (x̄ = 49 ± 12 μm, n = 43) thick (out of the inner layers), usually parallel to receptacle, forming an inverted arched or irregular shaped, not obvious change in textura angularis cells on diameter, slightly larger on textura prismatica cells, brown; terminal cells at the margin, indistinctively elongated. Paraphyses 1.5-2.8 μm (x̄ = 2.1 ± 0.4 μm, n = 80) wide, hyaline, filiform, rounded apex, 3-4-septate, sometimes branched at mid and base, with conspicuous contents and fine oil drops, scarcely extending beyond the asci. Asci (163.8-)170.9-197.4 × 10.1-15.5 μm (x̄ = 180.5 ± 7.2 × 12.6 ± 1.4 μm, n = 50), unitunicate, 8-spored, almost filling in some short asci, cylindric or subclavate, rounded apex with an amyloid apical pore in Melzer’s reagent, apical wall incrassated, 6.4-9.3(-10.3) × 2.7-5.1(-6.0) (x̄ = 7.8 ± 0.8 × 3.8 ± 0.7 μm, n = 40), thicken when immature, tapering to subtruncated base, croziers present. Ascospore 32.5-42.4 × 4.8-7.1 μm (x̄ = 36.3 ± 2.6 × 6.5 ± 0.4 μm, n = 50), Q = 4.4-6.5(-7.2), Qm = 5.6 ± 0.4, uniseriate or overlapping uniseriate, elongated to narrow fusiform with 1-2 guttules to multiple granules, hyaline, slightly curved, bluntly rounded at the base, slightly pointed at the apex, thin-walled, smooth and aseptate. Asexual morph: Undetermined.

Material examined.

China, Yunnan Province, Puer City, Jingdong County, altitude 1455 m, on the decayed wood, 23 August 2022, Cuijinyi Li , LCJY-1218 (HKAS 128273, holotype); ibid., Tengchong City, altitude 1714 m, on decayed wood, 16 August 2022, Cuijinyi Li, LCJY-1119-2 (HKAS 128272, paratype) .

Notes.

The distinctive characteristics of T. yunnanensis are large (4.8 mm wide), brown apothecia with pastel green to light green discs and short stipes, thick medullary excipulum comprising 2-10 layers of inverted proliferous cells, arched or irregular shaped, pleurorhynchous asci with J+ pores, filiform, 3-septate paraphyses and elongated fusiform ascospores without septa.

Phylogenetically, our collections clustered sister to T. macrospora with 98% ML bootstrap support and 1.0 Bayesian probability in the combined LSU and ITS phylogeny (Fig. 2 ). It was shown that the two species do not have any genetic recombination (Φw = 1.0) based on the pairwise homoplasy index (PHI) value (Fig. 3 ). Tatraea yunnanensis resembles T. macrospora in having cupulate apothecia, yellowish-white to orange-white discs when fresh and large ascospores. In contrast, our species differ from T. macrospora by having longer ascospores (32.5-42.4 μm vs. 22-40 μm) with 3-8-septate ascospores ( Baral et al. 1999). For T. macrospora , the morphological descriptions provided in previous studies are incomplete and lack details on the apothecial size and color, stalk and spores.

Figures

Figure 2. Maximum likelihood tree based on a combined dataset of LSU and ITS sequences for the genus Tatraea. The ML bootstrap proportions (ML-BP) equal to or higher than 70 % and Bayesian posterior proportions (BI-PP) equal to or higher than 0.90 are shown near the branches on the phylogenetic tree. Newly generated isolates of the current study are shown in blue and ex-types are shown in bold.

Figure 3. The results of the pairwise homoplasy index (PHI) test for the closely related species in Tatraea using LogDet transformation. A. PHI test for Tatraea yunnanensis vs. Tatraea macrospora. B. PHI test for Tatraea yuxiensis vs. Tatraea aseptata. C. PHI test for T atraea Tatraea clepsydriformis vs. Tatraea griseoturcoisina. PHI test results (Φw <0.05) indicate significant recombination within the dataset.

Figure 7. Tatraea yunnanensis (HKAS 128273, holotype) a-b fresh ascomata on the wood c dried ascomata on the wood d vertical section of an ascoma e-g excipulum h paraphyses i-m asci (m asci in Meltzer's reagent) n-s ascospores. Scale bars: 3.5 mm (c); 1200 μm (d); 300 μm (e); 50 μm (f); 100 μm (g); 80 μm (h-m); 20 μm (n-s).