FungiDiaporthalesDiaporthaceaeYangQinFanXin-LeiGuarnacciaVladimiroTianCheng-MingHigh diversity of Diaporthe species associated with dieback diseases in China, with twelve new species describedMycoKeys17920182018399714910.3897/mycokeys.39.26914 Diaporthe ukurunduensis MB824715 C.M. Tian & Q. Yangsp. nov.Figure 16Diagnosis.

Diaportheukurunduensis can be distinguished from the phylogenetically closely related species D.citrichinensis in longer conidiophores and shorter alpha conidia.

Holotype.

CHINA. Shaanxi Province: Qinling Mountain, on symptomatic twigs of Acerukurunduense, 27 June 2017, Q. Yang (holotype: BJFC-S1503; ex-type culture: CFCC 52592).

Etymology.

Named after the host species on which it was collected, Acerukurunduense.

Description.

Conidiomata pycnidial, immersed in bark, serried, slightly erumpent through the bark surface, nearly flat, discoid, with a single locule. Ectostromatic disc dark brown to black, one ostiole per disc. Locule circular, undivided, 165–215 μm diam. Conidiophores 11.5–18 × 1.5 μm, hyaline, branched, cylindrical, straight or curved. Alpha conidia hyaline, aseptate, ellipsoidal to oval, biguttulate, 5–6 × 2.1–2.9 μm (av. = 5.5 × 2.5 μm, n = 30). Beta conidia not observed.

Diaportheukurunduensis (CFCC 52592) A Habit of conidiomata on branches B Transverse section of conidioma C–D Alpha conidia E Conidiophores F Culture on PDA. Scale bars: 200 μm (B), 10 μm (C–E).

Culture characters.

Cultures incubated on PDA at 25 °C in darkness. Colony originally flat with white aerial mycelium, becoming brown to pale black in the centre, dense, felted, conidiomata not observed.

Additional specimens examined.

CHINA. Shaanxi Province: Qinling Mountain, on symptomatic twigs of Acerukurunduense, 27 June 2017, Q. Yang, living culture CFCC 52593 (BJFC-S1503).

Notes.

Diaportheukurunduensis comprises strains CFCC 52592 and CFCC 52593 closely related to D.citrichinensis in the combined phylogenetic tree (Fig. 1). Diaportheukurunduensis can be distinguished from D.citrichinensis based on ITS and tef1 loci (10/470 in ITS and 4/336 in tef1).

Phylogram of Diaporthe from a maximum likelihood analysis based on combined ITS, cal, his3, tef1 and tub2. Values above the branches indicate maximum likelihood bootstrap (left, ML BP ≥ 50%) and bayesian probabilities (right, BI PP ≥ 0.70). The tree is rooted with Diaporthellacorylina. Strains in the current study are in blue.