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

Fig. 5

Etymology.

The specific epithet refers to the hourglass shape apothecia.

Holotype.

HKAS 128275.

Description.

Saprobic on the decayed branches of oak tree. Sexual morph: Apothecia 1.3-3.5 mm wide (x̄ = 2.5 ± 0.7 mm, n = 13) when fresh, 0.9-1.3 mm wide × 0.6-0.9 mm high (x̄ = 1.1 ± 0.15 × 0.7 ± 0.12 mm, n = 13) when dry, gregarious, superficial, hourglass shape or cupulate, glabrous, with a wide stipe. Disc flat and circular, pale grey (5C1) when fresh, edge slightly curl inward towards the disc, melon yellow (5A6) to apricot yellow (5B6) or pale orange (5A2) near the center, darken to concolorous as receptacle near the edge when dry, or dark blue (20E7) when immature. Margins concolorous to the disc when fresh, white, smooth or dentate when dry. Receptacle slightly rough and dark yellowish brown (5D8) when fresh, slightly rough, light brown (6D8) to hazel brown (6E8) when mature and dry, sometimes edge with white narrow-band, smooth and dark blackish blue (20F8) when immature and dry. Stipe 360-596 μm wide × 463-571 μm long (x̄ = 470 ± 85 × 515 ± 47 μm, n = 13), short and broad, concolorous to the receptacle or pale yellow when fresh, concolorous to dried receptacle when mature, butter yellow (4A5) when immature, slightly rough on surface. Hymenium 122-155 μm (x̄ = 135 ± 12 μm, n = 30), hyaline. Subhymenium (24-)36-60(-65) μm (x̄ = 44 ± 8 μm, n = 37), dense golden brown (5D7) hyphae, forming textura intricata, hyphae 2.2-2.9 μm (x̄ = 2.6 ± 0.2 μm, n = 25) wide. Medullary excipulum 335-535 μm (x̄ = 415 ± 51 μm, n = 15) thick, well-developed, comprised of thin-walled, septate, branched, pale brown and slightly loose hyphae of textura intricata in center, hyphae 3.3-5.1 μm (x̄ = 4.2 ± 0.5 μm, n = 45) diam., hyaline, near the ectal excipulum becoming well-organized parallel, non-gelatinous. Ectal excipulum 29-80 μm (x̄ = 50 ± 14 μm, n = 48) thick, comprised of 3-5 layers, large cells inside and several outer layers of smaller cells of textura angularis, 4.9-15.3 μm (x̄ = 8.9 ± 2.4 μm, n = 64) diam., wall moderately thick, 0.5-1.1 μm (x̄ = 0.7 ± 0.1 μm, n = 52) thick, pale brown to pale yellow from the outer inward the inner layers; proliferous cells not observed; terminal cells at margin inconspicuous elongated. Paraphyses 2.1-3.4 μm (x̄ = 2.6 ± 0.3 μm, n = 45) wide, hyaline, straight and filiform, apically round, 1-3-septate, unbranched, no conspicuous contents, scarcely extending beyond the asci. Asci (104.0-)112.4-135.8 × 8.2-12.2 μm (x̄ = 121.5 ± 5.7 × 10.1 ± 0.9 μm, n = 40), unitunicate, 8-spored, cylindric or subclavate, apically rounded with an amyloid apical pore in Melzer’s reagent, apical wall incrassated, 5.0-8.5 μm wide × 2.0-3.7(-4.4) μm high (x̄ = 6.8 ± 0.7 × 3.1 ± 0.5 μm, n = 40), slightly constricted downward when immature, tapering to a cylindric and aporhynchous, subtruncated base, croziers present. Ascospore (12.9-)14.0-17.9 × 5.1-6.8 μm (x̄ = 15.2 ± 0.9 × 5.7 ± 0.4 μm, n = 65), Q = 2.1-3.2, Qm = 2.7 ± 0.1, overlapping uniseriate, ellipsoidal with a large guttule, obtusely rounded at both ends, slightly pointed at the base, hyaline, almost symmetrical, thin-walled, smooth and aseptate. Asexual morph: Undetermined.

Material examined.

China, Yunnan Province, Puer City , Jingdong County, altitude 2455 m, on the decayed oak tree twig, 23 August 2022, Cuijinyi Li, LCJY-1226 (HKAS 128275, holotype) ; ibid., Kunming City, Panlong District , altitude 1920 m, on the decayed oak tree twig with ant nests, 29 May 2022, Cuijinyi Li, LCJY-497 (HKAS 128266, paratype) ; ibid., Yeya Lake , altitude 1900 m, on the decayed oak tree twig with ant nests, 3 July 2021, Cuijinyi Li, LCJY-127 (HKAS 128264, paratype) ; ibid., Sanjian Mountain , altitude 1950 m, on decayed wood, 18 December 2021, Cuijinyi Li, LCJY-392 (HKAS 128267, paratype) .

Notes.

The distinctive characteristics of T. clepsydriformis are moderate-sized apothecia (2.5 mm wide when fresh), with fresh brown receptacles and stipes, light brown to hazel brown at dry condition, stipes concolorous to receptacles, pale yellow, proliferous cells of ectal excipulum not observed, aporhynchous asci and small, ellipsoidal ascospores without septa.

Phylogenetically, our collections clustered with T. griseoturcoisina with 85% ML bootstrap support and 0.96 Bayesian probability in the combined LSU and ITS phylogeny (Fig. 2 ). Morphologically, both species have small ascospores shown in Suppl. material 1 (shorter than 23 μm). Tatraea clepsydriformis are distinguished from other species by their shorter asci and smaller ascospores except for T. griseoturcoisina (Suppl. material 1). Tatraea clepsydriformis differs from T. griseoturcoisina by having brown receptacles, a broader medullary excipulum (335-535 μm vs. 164-308 μm) and shorter ascospores (15.2 × 5.7 μm vs. 17.1 × 5.4 μm).

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 5. Tatraea clepsydriformis (HKAS 128275, holotype) a-b fresh ascomata on the wood c-f dried ascomata on the wood g vertical section of an ascoma h-j excipulum k paraphyses l-p asci (o-p asci in Meltzer's reagent) q-r ascospores. Scale bars: 2 mm (c); 600 μm (d); 700 μm (e); 250 μm (f); 800 μm (g); 150 μm (h, j); 100 μm (i); 60 μm (k-p); 40 μm (q-r).