Derxomyces henanensis C. Y. Chai & F. L. Hui sp. nov.

Fig. 3

Etymology.

The specific epithet henanensis refers to the geographic origin of the type strain, Baotianman Nature Reserve, Nanyang City, Henan Province.

Typus.

China • Henan Prov.: Nanyang City, Baotianman Nature Reserve, on the phylloplane of Corydalis balansae, August 2022, J. Z. Li, NYNU 2211270 (holotype GDMCC 2.336 T preserved as a metabolically inactive state, culture ex-type PYCC 9941).

Description.

On YM agar after 7 days at 20 ° C, the streak culture is pale-yellow, butyrous and smooth, with an entire margin. After 3 days in YM broth at 20 ° C, cells are ovoid and ellipsoidal, 3.2–3.8 × 6.3–8.5 μm and single, budding is polar. After 1 month at 20 ° C, a ring and sediment are present. In Dalmau plate culture on CMA, pseudohyphae and hyphae are not formed. Ballistoconidia are produced on corn meal agar and are ovoid, 2.2–3.5 × 3.5–5.5 μm. Sexual structures are not observed on PDA, CMA or V 8 agar. Glucose fermentation is absent. Glucose, sucrose (weak and delayed), raffinose (delayed), melibiose (weak and delayed), galactose (delayed), maltose (weak and delayed), melezitose (weak and delayed), methyl-α-D-glucoside (delayed), salicin (delayed), L-rhamnose (delayed), D-xylose, L-arabinose, D-arabinose, 5 - keto-D-gluconate, D-ribose, ribitol, galactitol, D-glucitol (delayed), DL-lactate (delayed), succinate, citrate (weak and delayed), D-glucosamine (weak), N-acetyl-D-glucosamine (delayed), D-glucuronate (weak and delayed) and glucono- 1, 5 - lactone (weak) are assimilated as sole carbon sources. Inulin, lactose, trehalose, cellobiose, L-sorbose, methanol, ethanol, glycerol, erythritol, D-mannitol, myo-inositol, D-gluconate and 2 - keto-D-gluconate are not assimilated. L-Lysine is assimilated as the sole nitrogen source. Nitrate, nitrite, ethylamine and cadaverine are not assimilated. Growth is observed on YM agar at 25 ° C, but not at 30 ° C. Growth on 50 % (w / w) glucose-yeast extract agar is negative. Growth in vitamin-free medium is positive. Starch-like substances are not produced. Urease activity is positive. Diazonium Blue B reaction is positive.

Additional strain examined.

China • Nanyang City, Baotianman Nature Reserve, on the phylloplane of Corydalis balansae, August 202, J. Z. Li, NYNU 2211270 and NYNU 2211264.

GenBank accession numbers.

Holotype GDMCC 2.336 T (ITS: OP 954741, D 1 / D 2: OP 954742); additional strains NYNU 2210175 (ITS: OP 954655, D 1 / D 2: OP 954654) and NYNU 2211264 (ITS: PV 404187, D 1 / D 2: PV 404186).

Note.

Physiologically, D. henanensis can be distinguished from the closely-related species D. pseudoschimicola, D. melastomatis and D. komagatae in its inability to assimilate trehalose, cellobiose, D-mannitol and myo-Inositol, while being able to grow in vitamin-free medium (Table 2).