Dendrostoma dispersum C.M. Tian & N. Jiang sp. nov. Figure 7

Diagnosis.

Dendrostoma dispersum can be distinguished from the phylogenetically closely related D. mali and D. quercinum based on its conidial dimensions.

Holotype .

CHINA. Shaanxi Province: Beijing City: Mentougou District, Xiaolongmen Forest Park, 39°55'52"N, 115°45'15"E, 1670 m a.s.l., on branches of Quercus sp., 15 Aug. 2017, N. Jiang & X.L. Fan (holotype: BJFC-S1537; ex-type culture: CFCC 52730).

Etymology.

Dispersum, referring to the conidiomata scattered on the bark surface.

Description.

Sexual morph not observed. Asexual morph: Conidiomata pycnidial, conical to spherical, occurring separately, bright yellow, semi-immersed in bark, 500-800 μm high, 900-1500 μm diam.; wall of several layers of bright yellow textura angularis; central column beneath the disc conical, bright yellow. Conidiophores reduced to conidiogenous cells. Conidiogenous cells lining the inner walls of the cavity, hyaline, smooth, subcylindrical to ampulliform, 6-15 × 2.5-5 μm . Conidia hyaline, aseptate, smooth, multiguttulate, thin-walled, ellipsoid to fusoid, straight to curved, (10.9 –)11.1–12.2(– 12.8) × (1.9 –)2–2.3(– 2.4) μm, l/w = (4.8 –)4.9–5.9(– 6.3) (n = 50).

Culture characters.

On PDA, cultures are initially white, becoming faint yellow after 2 weeks. The colonies are flat with regular edge; texture uniform, producing concentric circles within 1 month at 25 °C in the dark.

Additional specimen examined.

CHINA. Beijing City: Yanqing District, Yudu Mountain, 40°53'48"N, 115°54'48"E, 840 m a.s.l., on branches of Quercus sp., 12 Mar. 2018, N. Jiang, X.L. Fan, Y.M. Liang & C.M. Tian, living culture CFCC 52731 (BJFC-S1538).

Notes.

Dendrostoma dispersum is phylogenetically close to D. mali and D. quercinum (Fig. 2). Conidial dimensions of Dendrostoma mali and D. quercinum were described from PDA plates (Fan et al. 2018) and D. dispersum can be differentiated from D. mali by having much longer conidia (11.1-12.2 μm in D. dispersum vs. 3-4.5 μm in D. mali) and from D. quercinum by narrower conidia (2-2.3 μm in D. dispersum vs. 2.5-3 μm in D. quercinum).