Microsporomyces pseudomagnisporus Q.M. Wang, F.Y. Bai & A.H. Li, 2020

Li, A. - H., Yuan, F. - X., Groenewald, M., Bensch, K., Yurkov, A. M., Li, K., Han, P. - J., Guo, L. - D., Aime, M. C., Sampaio, J. P., Jindamorakot, S., Turchetti, B., Inacio, J., Fungsin, B., Wang, Q. - M. & Bai, F. - Y., 2020, Diversity and phylogeny of basidiomycetous yeasts from plant leaves and soil: Proposal of two new orders, three new families, eight new genera and one hundred and seven new species, Studies In Mycology 96, pp. 17-140 : 115

Microsporomyces pseudomagnisporus Q.M. Wang, F.Y. Bai & A.H. Li sp. nov. MycoBank MB828820. Fig. 15I, J .

Etymology: the specific epithet pseudomagnisporus refers to the similar colony morphology to that of Microsporomyces magnisporus .

Culture characteristics: In YM broth, after 7 d at 17 °C, cells are cylindrical, 2.0– 3.0 × 4.0–8.0 μm and single, budding is polar ( Fig. 15I ), a sediment is formed. After 1 mo at 17 °C, a part ring and sediment are present. On YM agar, after 1 mo at 17 °C, the streak culture is orange, butyrous, wrinkled and semi-glossy. The margin is entire. In Dalmau plate culture on corn meal agar, pseudohyphae are not formed. Sexual structures are not observed on YM, PDA, V8 and CM agar. Ballistoconidia are allantoid or reniform, 2.5– 3.3 × 5.8– 8.3 μm ( Fig. 15J ).

Physiological and biochemical characteristics: Glucose fermentation is absent. Glucose, galactose, L-sorbose, sucrose, trehalose (weak), melibiose (weak), raffinose (weak), melezitose (weak), inulin (delayed), D-arabinose (weak), ethanol, ribitol (weak), D-mannitol (weak), D-glucitol (weak), Methyl-α- Dglucoside (weak) and succinate (weak) are assimilated as sole carbon sources. Maltose, cellobiose, lactose, soluble starch, Dxylose, L-arabinose, D-ribose, L-rhamnose, D-glucosamine, N- Acetyl-D-glucosamine, methanol, glycerol, erythritol, galactitol, salicin, DL-lactate, citrate, myo-inositol and hexadecane are not assimilated. Ammonium sulfate, potassium nitrate, L-lysine, ethylamine hydrochloride and cadaverine dihydrochloride are assimilated as sole nitrogen sources. Sodium nitrite is not assimilated. Maximum growth temperature is 19 °C. Growth in vitamin-free medium is postive. Starch-like substances are not produced. Growth on 50 % (w/w) glucose-yeast extract agar is negative. Urease activity is positive. Diazonium Blue B reaction is positive.

Physiologically, Mi. pseudomagnisporus differs from its closely related species Mi. magnisporus in its inability to assimilate maltose, soluble starch, N-Acetyl-D-glucosamine, DL-lactate, citrate and sodium nitrite and its ability to assimilate inulin, ethanol, L-lysine, ethylamine and cadaverine ( Table S1.24 ).

Typus: China, Fanjingshan Mountain , Guizhou province, obtained from a leaf of an unidentified plant, Oct. 2011, Q.-M. Wang (holotype CGMCC 2.4538 T preserved in a metabolically inactive state, ex-type CBS 15746 = FJS25C3).

Figures

Fig. 15. Vegetative cells grown in YM broth for 5 d at 17 °C and ballistoconidia produced on corn meal agar after 7 d at 17 °C. (A, B) Phy. aceris CGMCC 2.2662T; (C) Phy. jiayinensis CGMCC 2.5669T; (D) Me. layueensis CGMCC 2.5818T; (E) Sa. melibiophila CBS 5143T; (F) Mi. ellipsoideus CGMCC 2.5664T; (G, H) Mi. rubellus CGMCC 2.4444T; (I, J) Mi. pseudomagnisporus CGMCC 2.4538T; (K, L) Sy. rhododendri CGMCC 2.2613T; (M) Cy. raffinophilum CGMCC 2.3822T; (N) Cy. terricola CGMCC 2.3823T, (O) Do. ningxiaensis CGMCC 2.4451T; (P) Beg. foliicola CGMCC 2.3164T. Bars = 10 μm.