Orbilia laevimarginata Baral, Y. Zhang & Z.F. Yu, 2015

Zhang, Ying, He, Xiaoxia, Baral, Hans-Otto, Qiao, Min, Wei, Michael, Liu, Bin, Zhang, Ke-Qin & Yu, Zefen, 2015, Orbilia laevimarginata sp. nov. and its asexual morph, Phytotaxa 203 (3), pp. 245-253 : 247-249

Orbilia laevimarginata Baral, Y. Zhang & Z.F. Yu , spec. nov. MycoBank MB 809733

Etymology: names after the smooth apothecial margin.

Type:— CHINA. Yunnan: Kunming City,—Qinglongxia (Yu’an mt.), Anning city, 1926 m, N 25°03’ E 102°22’, on bark and wood of Quercus , 3. XI. 2004, Z.F. Yu (qlx-1, H.B. 7667, without culture) holotype H.B. 7667, deposited in M (Botanische Staatssammlung München, Germany).

Apothecia sessile, gregarious, superficial, 0.3–1.2 mm in diam., smooth, plane, translucent, light coloured, pale pink to whitish when fresh, with an even margin or sometimes with prominent broad teeth 25–30 × 60–80 μm, 12–14 per apothecium, darker and irregularly undulating and concave when dry. Asci 8-spored, 23–28(–32) × 3.4–3.6 μm (living state), 20–27 × (2.5–)2.9–3.1(–3.2) μm (dead state), cylindric-clavate, usually tapered below and forked at the base, with a truncate to rounded apex. Ascospores hyaline, non-septate, symmetrically crossed in the ascus, distinctly helicoidally twisted, with a broad, acute upper and a tapered lower end, (6–)7–8(–9) × 0.7–1 μm, bearing a tear-shaped refractive spore body (SB) at the upper end, 1.8–2.2 × 0.3–0.5 μm, fully filling the apex of the ascospore. Paraphyses hyaline, not or only slightly enlarged at the apex (2–3.2 μm in diam.), the apex being immersed in a 0.2–0.5 μm thick exudate. Ectal excipulum composed of angular or subangular cells, with thin or only slightly thickened walls of 5–14 μm in diam. 13–22 × 11–17 μm, at the upper margin of elongated cells oriented at a low angle to the surface, sometimes terminated by 1.5–2.5 μm long glassy processes.

Colonies on CMA whitish, growing slowly, reaching 28 mm at 25 º after 10 days. Mycelium spreading, scanty, vegetative hyphae hyaline, septate, branched, 5.0–6.3 μm wide, often forming spirally coiled rings. Conidiophores hyaline, erect, more or less branched, septate, originating from both prostrate and aerial mycelium, 41–50 μm long, 3–4.3 μm wide at the base, tapering gradually upward to 1.3–1.6 μm at the tip, here bearing 1–10 denticles about 2–5 μm long and 1.3–1.6 μm wide, each with a single conidium to form capitate arrangements, occasionally proliferating to form additional clusters. Conidia cylindric-ellipsoid to oblong, broadly rounded at the distal end, tapered at the proximal end, partly with a definite pedicle, 10.2–13 × 3.0–4.0 μm (YMF1.01833), 7.6–12.5 × 3.0–4.0 μm (YMF1.01869) and 8.2–12.2 × 2.3–4.0 μm (YMF1.03013), (0–)1(–3)-septate, the proximal cell 5.4–7.8 μm long with a ratio of approximately 1:1 to the distal cell, occasionally constricted at the septum, containing several small LBs. Trapping devices were not observed when nematodes were added. Chlamydospores were not observed.

Included collections: China: Yunnan prov., Kunming City,— Qinglongxia (Yu’an mt.), Anning city, N 25°03’ E 102°22’, 1926 m, on bark and wood of Quercus , 3. XI. 2004, Z. F. Yu (qlx-1, H. B. 7667, without culture) ,— Bamboo temple ( Yu’an mt. ), 9 km WNW of Kunming, N 25°04’ E 102°37’, 2140 m, on wood of Quercus, VII. 2005 , Y. Zhang (ya-17, YMF / YMFT 1.01833 ) .— Yuxi City, Yimen county, 54 km NW of Yuxi, 3 km NW of Fangtunxiang, 1580 m, Dalongkou (Longquan) Forest Park, (24° 41’ N, 102° 8’ E, elevation 1750 m) on wood of Quercus, VIII. 2006 and VIII. 2007, Z. F. Yu & S. F. Li (ym-87, YMF / YMFT 1.01869 ; ym3-52, YMF / YMFT1.03013 ) .— Jinghong City, Xishuangbanna Autonomous Prefecture , altitude 1000 m, unidentified wood, 9.XI.2002, B. Liu et al. ( HMAS 139521 ) .