Stylonectria qilianshanensis Z.Q. Zeng & W.Y. Zhuang, 2020

Zeng, Zhao-Qing, Zheng, Huan-Di, Wang, Xin-Cun, Wei, Sheng-Long & Zhuang, Wen-Ying, 2020, Ascomycetes from the Qilian Mountains, China - Hypocreales, MycoKeys 71, pp. 119-137 : 119

Stylonectria qilianshanensis Z.Q. Zeng & W.Y. Zhuang sp. nov. Figure 3

Holotype.

China. Gansu Province, Wuwei, Chashugou, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 26 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12155 (HMAS 255803).

Paratypes.

China. Zhangye, Longchanghe, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 24 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12016, 12017 (HMAS 255804, 255805); Kangle, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 24 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12035, 12036, 12037, 12038 (HMAS 255806, 255807, 255808, 255809); Shandan, Yanzhishan, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 25 August 2018, H.D. Zheng, X.C. Wang & Z.Q. Zeng 12082 (HMAS 255810); Yanzhishan, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 25 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12086, 12087, 12088, 12089, 12090 (HMAS 255811, 255812, 255813, 255814, 255815); Wuwei, Chashugou, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 26 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12148, 12153, 12156, 12158 (HMAS 255816, 255817, 255818, 279708); Tianzhu, Kelacun, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 27 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12229 (HMAS 279709); Haxi, on decayed fruitbodies of an ascomycete on bark of Picea asperata , 28 August 2018, Z.Q. Zeng, X.C. Wang & H.D. Zheng 12276, 12278 (HMAS 255819, 255820).

Etymology.

The specific epithet refers to the type locality.

Description.

Perithecia gregarious, up to 30 in a group, parasitic on decayed fruitbodies of an ascomycete, deep red to dark red, turning black red in 3% KOH and light yellow in 100% LA, subglobose to globose, not becoming cupulate upon drying, (216-)255-344 × (186-)206-304 μm (n = 12), apex broadly discoid, flattened, 50-70 μm high, 160-220 μm in diameter, slightly constricted below, with a tiny papilla. Perithecial wall of two layers, 25-38 μm thick, outer layer 20-31 μm, of textura angularis, cells 5-8 × 2-4 μm, walls 0.8-1.0 μm thick; inner layer 5-7 μm, of textura prismatica, cells 8-12.5 × 3-5 μm, walls 0.5-0.8 μm thick. Asci clavate, with an apical ring, 8-spored, 55-88 × 5-8(-10) μm. Ascospores ellipsoidal, ends rounded, 1-septate, light brown, smooth, uniseriate, 10-13 × 5-5.5 μm. Asexual state unknown.

Distribution.

China.

Notes.

Stylonectria qilianshanensis is morphologically similar to S. wegeliniana in having the perithecia with a broad, discoid apex, clavate asci with an apical ring, and ellipsoidal ascospores with rounded ends ( Petch 1938). However, S. qilianshanensis differs in having smaller asci [55-88 × 5-8(-10) μm vs 90-100 × 9-10 μm] and ascospores (10-13 × 5-5.5 μm vs 10-18 × 6-9 μm) ( Petch 1938). Sequence comparisons indicate that ITS of S. qilianshanensis differs from that of S. wegeliniana by 20 bp in a total length of 576 bp; ACL1 and RPB2 of the former differ from those of the latter by 84 bp and 38 bp, respectively among 722 bp and of 869 bp in length. The asexual state of the fungus remains unknown until culture is available.

Figures

Figure 3. Stylonectria qilianshanensis a-c ascomata on natural substrate d-f median section through perithecium g-l ascus with ascospores m-q ascospores. From HMAS 255803. Scale bars: 1 mm (a-c); 50 μm (d-f); 10 μm (g-q).