Dioszegia aurantia Y.Z. Qiao & F.L. Hui, 2024

Qiao, Ya-Zhuo, Liu, Shan, Niu, Qiu-Hong & Hui, Feng-Li, 2024, Three new Dioszegia species (Bulleribasidiaceae, Tremellales) discovered in the phylloplane in China, MycoKeys 101, pp. 313-328 : 313

Dioszegia aurantia Y.Z. Qiao & F.L. Hui sp. nov.

Fig. 2C

Etymology.

The specific epithet aurantia refers to the aurantiaca colony morphology.

Typus.

China, Guizhou Province, Guiyang City, Guiyang Botanical Garden, in the phylloplane of Cornus officinalis , September 2022, L. Zhang and F.L. Hui, NYUN 229189 (holotype GDMCC 2.335T preserved as a metabolically inactive state, culture ex-type PYCC 9937 and CICC 33572).

Description.

On YM agar, after 7 days at 20 °C, the streak culture is orange, butyrous, smooth. The margin is entire. On YM agar, after 7 days at 20 °C, cells are ovoid and ellipsoidal, 4.6-5.0 × 5.0-8.2 μm and single, budding is polar. After 1 month at 20 °C, a ring and sediment are present. In Dalmau plate culture on corn meal agar, hyphae and pseudohyphae are not formed. Sexual structures are not observed for individual strains and strain pairs on PDA, CM agar, and YCBS agar for two months. Ballistoconidia are not produced on CM agar after two weeks at 20 °C. Glucose fermentation is absent. Glucose, inulin, sucrose, raffinose, melibiose, galactose, trehalose, maltose, melezitose, methyl-α-D-glucoside (delayed), cellobiose, salicin (weak), L-sorbose (delayed), L-rhamnose (delayed and weak), D-xylose, L-arabinose, D-arabinose (weak), 5-keto-D-gluconate, D-ribose, galactitol, D-mannitol, D-glucitol, succinate (weak), N-acetyl-D-glucosamine, 2-keto-D-gluconate (delayed and weak), and D-glucuronate are assimilated as carbon sources. Lactose, methanol, ethanol, glycerol, erythritol, ribitol, myo-inositol, DL-lactate, citrate, D-gluconate, D-glucosamine, and glucono-1,5-lactone are not assimilated. Nitrite (delayed) and L-lysine (delayed and weak) are assimilated as nitrogen sources. Nitrate, ethylamine, and cadaverine are not assimilated. Maximum growth temperature is 25 °C. Growth in vitamin-free medium is negative. Starch-like substances are produced. Urease activity is positive. Diazonium Blue B reaction is positive.

GenBank accession numbers.

Holotype GDMCC 2.335T (ITS: OP566892, D1/D2: OP566893).

Note.

Dioszegia aurantia sp. nov. can be physiologically differentiated from its closest known species D. maotaiensis ( Li et al. 2020) by its inability to assimilate citrate, its ability to assimilate methyl-α-D-glucoside, salicin, L-sorbose, D-ribose, D-mannitol, D-glucitol, and N-acetyl-D-glucosamine, and its capacity to grow in vitamin-free medium and at 30 °C.

Figures

Figure 2. Vegetative cells of Dioszegia guizhouensis sp. nov. NYNU 22985 T (A), Dioszegia foliicola sp. nov. NYUN 229182 T (B), and Dioszegia aurantia sp. nov. NYNU 229189 T (C) following growth in YM broth for 7 days at 20 ° C. Scale bars: 10 μm.