Vishniacozyma guiyangensis C. Y. Chai & F. L. Hui, 2025

Vishniacozyma guiyangensis C. Y. Chai & F. L. Hui sp. nov.

Fig. 2 B View Figure 2

Etymology.

The specific epithet guiyangensis refers to the geographic origin of the type strain, Guiyang city, Guizhou Province.

Typus.

China. • Guizhou Prov.: Guiyang City, Guiyang Medicinal Botanical Garden (26°34'51"N, 106°42'36"E), Aug 2022, in the phylloplane of Distylium racemosum , L. Zhang & F. L. Hui, NYNU 22831 (holotype CICC 33569 View Materials T, GenBank: OP 566869 , OP 566870 ); culture ex-type PYCC 9934 View Materials GoogleMaps .

Description.

On YM agar after seven days at 20 ° C, the streak culture is white-cream, mucoid, glistening, and smooth, with an entire margin. After three days in YM broth at 20 ° C, cells are ovoid to ellipsoidal, 2.5–3.9 × 4.1–7.4 μm, and single; budding is polar. After one month at 20 ° C, sediment is present. In Dalmau plate culture on CMA, pseudohyphae and hyphae are not formed. Sexual structures are not observed on PDA, CMA or V 8 agar. On corn meal agar, ballistoconidia are not produced. Glucose fermentation is absent. Glucose, sucrose, raffinose, melibiose, galactose, lactose, trehalose, maltose, melezitose, methyl-α-D-glucoside, cellobiose, L-sorbose (delayed and weak), L-rhamnose, D-xylose, L-arabinose, D-ribose, glycerol, erythritol, galactitol (delayed), D-mannitol, D-glucitol, myo-inositol, DL-lactate, D-gluconate, D-glucosamine, N-acetyl-D-glucosamine, 2 - keto-D-gluconate, and D-glucuronate are assimilated as sole carbon sources. Inulin, salicin, D-arabinose, 5 - keto-D-gluconate, methanol, ethanol, ribitol, succinate, and glucono- 1, 5 - lactone are not assimilated. Nitrate, nitrite, ethylamine, L-lysine, and cadaverine are not assimilated as sole nitrogen sources. Maximum growth temperature is 25 ° C. Growth in vitamin-free medium is negative. Growth on 50 % (w / w) glucose-yeast extract agar is positive. Starch-like substances are not produced. Urease activity is positive. Diazonium Blue B reaction is positive.

Additional strain examined.

China. • Henan Prov.: Songxian Co., Tianchi mountain (34°32'27"N, 112°16'39"E), Jun 2023, in the phylloplane of Morus alba , J. Z. Li, NYNU 236231 (GenBank: PP 580372 , PP 580370 ), NYUN 236232 (GenBank: PP 580374 , PP 580373 ) GoogleMaps .

Note.

In the phylogenetic analyses, three strains of V. guiyangensis clustered in a single clade with full support values (BS / 100, BPP / 1.0; Fig. 1 View Figure 1 ), and V. guiyangensis was close to a clade formed by V. pingtangensis and V. eriobotryae , described in this study with significant support (BS / 97, BPP / 1.0; Fig. 1 View Figure 1 ). V. guiyangensis differs from V. pingtangensis by 92 nucleotides (65 / 501 in ITS and 27 / 600 in LSU) and from V. eriobotryae by 64 nucleotides (17 / 596 in ITS and 47 / 596 in LSU). Physiologically, V. guiyangensis can be differentiated from these species by its inability to assimilate salicin, D-arabinose, 5 - keto-D-gluconate, ribitol, succinate, and glucono- 1, 5 - lactone. In addition, V. guiyangensis can grow on 50 % (w / w) glucose-yeast extract agar, while the other two species cannot.