Neostagonosporella sichuanensis C.L. Yang, X.L. Xu & K.D. Hyde

Yang, Chun-Lin, Xu, Xiu-Lan, Wanasinghe, Dhanushka N., Jeewon, Rajesh, Phookamsak, Rungtiwa, Liu, Ying-Gao, Liu, Li-Juan & Hyde, Kevin D., 2019, Neostagonosporellasichuanensis gen. et sp. nov. (Phaeosphaeriaceae, Pleosporales) on Phyllostachysheteroclada (Poaceae) from Sichuan Province, China, MycoKeys 46, pp. 119-150 : 126-127

Neostagonosporella sichuanensis C.L. Yang, X.L. Xu & K.D. Hyde sp. nov. Figs 2, 3

Type.

CHINA, Sichuan Province, Ya’an City, Yucheng District, Kongping Township, Alt. 1133 m, 29°50.14'N 103°03'E, on living to nearly dead branches of Phyllostachys heteroclada Oliv. ( Poaceae ), 8 April 2016, C.L. Yang and X.L. Xu, YCL201604001 (MFLU 18-1212/ SICAU 16-0001, holotype), ex-type living culture, MFLUCC 18-1228/ SICAUCC 16-0001; Sichuan Province, Ya’an City, Yucheng District, Yanchang Township, Alt. 951 m, 29°43.57'N 103°04.74'E, on nearly dead stems of Phyllostachys heteroclada Oliv. ( Poaceae ), 9 April 2017, C.L. Yang and X.L. Xu, YCL201704001 (MFLU 18-1220/ SICAU 17-0001, paratype), ex-type living culture, MFLUCC 18-1231/ SICAUCC 17-0001; Sichuan Province, Ya’an City, Lushan County, Longmen Township, Alt. 949 m, 30°15.74'N 102°59.27'E, on nearly dead branches of Phyllostachys heteroclada Oliv. ( Poaceae ), 12 September 2017, C.L. Yang and X.L. Xu, YCL201709002 (MFLU 18-1223, paratype).

Etymology.

in reference to Sichuan Province where the specimens were collected.

Description.

Associated with stem spot disease on living to nearly dead stems and branches of Phyllostachys heteroclada ( Poaceae ). Sexual morph: Ascostromata (0.5-) 1-2 (-4.5) × 0.8-1.3 mm long (x¯ = 1.9 × 1 mm, n = 50), 230-340 μm high (x¯ = 290 μm, n = 20), ellipsoidal, globose to subglobose or irregular in shape, immersed in host epidermis, becoming raised to superficial, coriaceous, solitary to gregarious, multi-loculate, erumpent through host tissue, with dark brown to black, glabrous, ostiole, usually generating subrhombic to rhombic pale yellow stripes at ascostromatal fringe. Locules 230-300 μm high (x¯ = 264 μm, n = 20), 330-460 μm diam. (x¯ = 393 μm, n = 20), clustered, gregarious, globose to subglobose, with a centrally located ostiole, lacking periphyses. Peridium 18-35 μm wide (x¯ = 27 μm, n = 20), composed of several layers of small, brown to dark brown pseudoparenchymatous cells of textura angularis, with inner hyaline layer, slightly thin at base, thick at sides towards apex, upper part fused with host tissue. Hamathecium composed of 1-2 μm (x¯ = 1.59 μm, n = 50) wide, filiform, septate, trabeculate, anastomosed pseudoparaphyses, embedded in a hyaline gelatinous matrix. Asci 90-125 × 12.5-14 μm (x¯ = 108.1 × 13.3 μm, n = 40), 8-spored, bitunicate, fissitunicate, cylindrical to cylindric-clavate, short pedicellate, 7.8-14 μm long (x¯ = 11 μm, n=20), apically rounded with an ocular chamber. Ascospores 30-35 × 6-7 μm (x¯ = 31.9 × 6.6 μm, n = 50), overlapping bi-seriate, hyaline, cylindrical to fusiform or subcylindric-clavate, with rounded to acute ends, narrower towards end cells, sometimes narrower at lower end cell, straight or slightly curved, 5-8 transversely septa, mostly 7-septate, slightly constricted at septa, nearly equidistant between septa, guttulate, smooth-walled, surrounded by a mucilaginous sheath, 5-9 μm thick (x¯ = 6.9 μm, n = 30). Asexual morph: Coelomycetous. Conidiostromata 9-13 × 1-2 mm long (x¯ = 11.2 × 1.6 mm, n = 10), 320-350 μm high (x¯ = 332 μm, n=10), fusiform to long fusiform or rhomboid, coriaceous, superficial, dark brown to black, multi-loculate, solitary, scattered, glabrous. Pycnidia 180-240 μm high (x¯ = 209 μm, n = 20), 170 -240 μm diam. (x¯ = 210 μm, n = 20), globose to subglobose, ostiolate. Pycnidial wall 12-18 (-23) μm wide (x¯ = 15 μm, n = 20), comprising multi-layered, brown to dark brown pseudoparenchymatous cells, of textura angularis, paler towards inner layers, slightly thin at base, thick at sides towards apex, upper part fused with host tissue. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 3-5.5 (-7) × 3-4 μm (x¯ = 4.17 × 3.29 μm, n = 20), ampulliform to subcylindrical, smooth, hyaline, enteroblastic, phialidic, formed from inner layer of pycnidial wall. Macroconidia (32.5-) 33.5-40 (-44) × (5-) 5.5-7 (-7.5) μm (x¯ = 37.5 × 6.2 μm, n = 40), subcylindrical to cylindrical, narrowly rounded at both ends, sometimes curved, 7-13 transversely septa, nearly equidistant between septa, hyaline, smooth-walled, guttulate, sometimes surrounded by a mucilaginous sheath when immature. Microconidia (3-) 3.5-4 (-5) × (1-) 1.5-2 (-3) μm (x¯ = 3.9 × 1.9 μm, n = 50), oval, ellipsoidal or elongate-ellipsoidal, aseptate, rounded at both ends, hyaline, smooth-walled, with small guttulate.

Culture characteristics. Ascospores germinating in sterilised water within 24 hours at 25°C, with germ tubes developed from each cell of ascospores, mostly from middle and end of spores. Colonies on PDA circular, with concentric circles, grey white in outer side, fawn in reverse side, grey in inner side, dark brown on back side. Conidial germination similar to ascospores. Conidiomata formed on PDA at 25°C after 75 days, pycnidial, solitary to gregarious, raised on agar, black dots, pyriform, globose to subglobose, or irregular, uniloculate, covered by white or grey hyphae. Conidia two types, macroconidia and microconidia and both longer than ones on host. Macroconidia (30 –)40–48(– 60.5) × (4 –)5– 6 μm (x¯ = 43.8 × 5.2 μm, n = 50), hyaline, 4-7-septate, occasionally 3-septate, hyaline. Microconidia (3.5 –)4–6(– 12) × (1 –)1.5–2(– 3) μm (x¯ = 5.3 × 1.9 μm, n = 50), aseptate, hyaline.