Vustinia terrae A.V. Kachalkin, Turchetti & Yurkov, in Kachalkin et al., Mycological Progress 18 (7): 956 (2019)
Etymology: The species epithet terrae is derived from terra (L. gen. sing. f., n., of the earth) and refers to the original substrate of isolation, namely soil.
Diagnosis: After 1 week at 20 °C on PD, GPY, and 2% glucose YNB agars, streak is orange, butyrous with a smooth glistening surface. Margins are smooth and entire. Cells are ellipsoidal to cylindrical 6–10 × 2–3 μm in size, occurring singly or in pairs, and proliferating by polar budding (Fig. 6). Lipid-like bodies can be present in cells. Pseudohyphae and true hyphae were not observed. Ballistoconidia were not observed. Teleomorph was not observed.
Glucose is not fermented. Positive growth on D-glucose, D-galactose, L-sorbose, D-ribose (weak), D-xylose, L-arabinose, D-arabinose (weak and delayed), L-rhamnose, sucrose, maltose (weak), trehalose, cellobiose, salicin (weak), arbutin (delay for some strains), melibiose (variable, delayed), lactose, raffinose (variable), melezitose (variable), soluble starch (variable, delayed), glycerol, erythritol, ribitol, xylitol (delay), D-mannitol, D-glucitol, 2-keto-D-gluconate, 5-keto-D-gluconate, D-gluconate, D-glucuronate (variable), succinate (delayed), and citrate (variable). No growth on D-glucosamine, methyl-alpha-D-glucoside, inulin, inositol, methanol, ethanol, galactitol, DL-lactate, L-malate, and ethyl acetate. Utilization of nitrogen sources: positive growth on potassium nitrate, sodium nitrite, lysine, and cadaverine. No growth in the presence of 10% sodium chloride, 50% D-glucose, and 0.01% cycloheximide. Growth on vitamin-free medium is weak. Urea hydrolysis and Diazonium Blue B reaction are positive. Starch-like compounds are produced. Maximum growth temperature: 25 °C.
Index Fungorum number: IF829116
Notes: New species of the genus Vustinia can be distinguished from known Krasilnikovozyma species by orange-colored pigmentation, positive growth on glycerol and erythritol and inability to grow on D-glucosamine.
Figure 1. Phylogenetic relationships of yeasts and related taxa from the order Cystofilobasidiales in Tremellomycetes obtained by maximum likelihood analysis of a concatenated alignment of the a ITS region and LSU (D1/D2 domains) rRNA gene and b ITS region, LSU rRNA gene, and TEF1. The numbers provided on branches are frequencies (> 50%) with which a given branch appeared in 100 bootstrap replications. The scale bars indicate the numbers of expected substitutions accumulated per site
Figure 2. Micrograph showing morphology of new species: Vustinia terrae (a), vegetative cells on PDA after 7 days at 20 °C. Scale bars = 10 μm.
Kachalkin, AV; Turchetti, B; Inacio, J; Carvalho, C; Mašínová, T; Pontes, A; Röhl, O; Akulov, A; Baldrian, P; Begerow, D; Buzzini, P; Sampaio, JP; Yurkov, AM. 2019. Rare and undersampled dimorphic basidiomycetes. Mycological Progress. 18(7):945-971