Dothiorella camelliae L.W. Li & Jian K. Liu, 2023

Li, Wen-Li, Liang, Rui-Ru, Dissanayake, Asha J. & Liu, Jian-Kui, 2023, Botryosphaerialean fungi associated with woody oil plants cultivated in Sichuan Province, China, MycoKeys 97, pp. 71-116 : 71

Dothiorella camelliae L.W. Li & Jian K. Liu sp. nov.

Fig. 12

Etymology.

The epithet ‘‘ camelliae ’’ refers to the host genus Camellia , on which the holotype was collected.

Holotype.

HKAS 125892.

Description.

Saprobic on decaying branches of Camellia oleifera . Sexual morph: Ascomata 199-222 × 237-269 μm (x̄ = 210.5 × 253 μm, n = 10), submerged in the substrate, partly erumpent at maturity, solitary or gregarious, dark brown to black, subglobose, multilocular or unilocular. Ostiole 17-37 μm diam., central. Peridium 35-43 μm wide, thick-walled, outer layers composed of 1-2 layers dark brown cells of textura angularis, becoming hyaline towards the inner region. Pseudoparaphyses 3-4 μm wide, hyaline, frequently aseptate. Asci 80-96 × 22-25 μm (x̄ = 88 × 23.5 μm, n = 30), stipitate, clavate, thick-walled, bitunicate, (6-)8-spored, irregularly biseriate. Ascospores 21-25 × 9.5-12 μm (x̄ = 23 × 10.5 μm, n = 30), L/W ratio = 2, oblong, ovate to sub-clavate, (0-)1-septate, slightly constricted at the septum, hyaline to dark brown, moderately thick-walled, straight or inequilateral, basal cell tapering towards the acute end. Asexual morph: Not observed.

Culture characteristics.

Ascospores germinate on PDA within 12 h. Colonies growing on PDA, reaching a diameter of 4 cm after five days at 25 °C, effuse, velvety, with entire to slightly undulate edge. Surface initially white and later turning dark olivaceous from the surrounding of the colony and dark gray in reverse.

Materials examined.

China, Sichuan Province, Leshan City, Wutongqiao District , 29°22'28"N, 103°45'49"E, elevation 383 m, on dead branches of Camellia oleifera ( Theaceae ), 23th July 2021, Z.P Liu, 351 (HKAS 125892, holotype), ex-type living culture UESTCC 22.0081 = CGMCC 3.24158 ; ibid., 347 (HUEST 22.0081), living culture UESTCC 22.0080 ; ibid., Shizhong District , 29°42'13"N, 103°52'25"E, elevation 356 m, on dead branches of Paeonia suffruticosa , 23th July 2021, W.L Li, A240 (HUEST 22.0080), living culture UESTCC 22.0079 ; ibid., A234 (HUEST 22.0079), living culture UESTCC 22.0078. Additional sequences: LSU: OQ164834 (CGMCC 3.24158), OQ164835 (UESTCC 22.0079), OQ164836 (UESTCC 22.0078) .

Notes.

Four strains isolated from Vernicia fordii and Camellia oleifera occupy a basal position in the Dothiorella phylogenetic tree by forming a well-supported subclade sister to Do. zanthoxyli (ML/BI 97%/1, Fig. 4 ). The BLASTn searches of the ITS sequence of Dothiorella zanthoxyli resulted in 97% matches with Neofusicoccum vitifusiforme BRIP64010, the tef1 showed 91.23% matches with Do. symphoricarposicola BL158, and the tub2 BLASTn results indicated 96.53% similarity with Do. uruguayensis CBS 124908 and Do. viticola B116-3. Dothiorella camelliae can be distinguished from Do. zanthoxyli in the size of ascomata, ascus and L/W ratio of ascospores (Table 3 ). Dothiorella camelliae resembles the sexual morph of Do. sarmentorum in producing immersed to sub-immersed ascomata, clavate asci and ovate to sub-clavate, hyaline to brown conidia with (0-)1-septate. However, Do. sarmentorum morphologically can be distinguished from Do. camelliae in having larger ascomata (350-400 μm vs. 237-269 μm), thicker peridium (50-75 μm vs. 35-43 μm), and longer asci (140-210 μm vs. 80-96 μm) (Table 3 ). Phylogenetically, these two species reside in two distinct clades.

Figures

Figure 4. Phylogram generated from RAxML analysis based on combined ITS, tef 1 and tub 2 sequence data of Dothiorella isolates. The tree was rooted to Neofusicoccum luteum (CBS 562.92 and CMW 41365). The ML (≥ 75 %) and BI (≥ 95 %) bootstrap supports are given near the nodes, respectively. Isolates from this study are marked in red and ex-type strains are marked in bold.

Figure 12. Dothiorella camelliae (HKAS 125892, holotype) a, b appearance of ascomata on natural substrate c vertical section of ascoma d section of peridium e-g asci h-m ascospores n germinated ascospore. Scale bars: 50 μm (c); 10 μm (d, h-n); 20 μm (e-g).