Sugiyamaella casensis M. Kolarik & R. Vadkertiova 2026, sp. nov.

Sugiyamaella casensis M. Kolařík & R. Vadkertiová sp. nov. Fig. 8 Etymology. The epithet casensis is derived from the acronym CAS (Czech Academy of Sciences) combined with the Latin suffix - ensis (i. e., originating from). The name honours the institution’s role in advancing scientific research in the Czech Republic. Diagnosis. Sugiyamaella casensis differs from the closely related species Sugiyamaella mastotermitis in its inability to ferment saccharides and to grow at 40 ° C. Moreover, unlike S. mastotermitis, it assimilates d-ribose, ribitol and glycerol (Suppl. material 13). The strain of S. mastotermitis was isolated from the gut contents of the termite Mastotermes darwiniensis (laboratory culture) in Germany (Handel et al. 2016), whereas S. casensis was isolated from the larvae of Treptoplatypus oxyurus in Slovakia. Type. SLOVAKIA • Zvolen region, Tŕnie, 48.627397°N, 19.029675°E; alt. 665 m.; from thorax of Treptoplatypus oxyurus feeding in the base (40 cm diam) of a decaying Abies alba; 10. June 2024; leg. M. Knížek, J. Vakula, M. Zúbrik, isol. M. Kolařík Tox- 17 (holotype CCY 101-1-1, culture preserved in a metabolically inactive state in the Culture Collection of Yeasts, Bratislava, Slovakia, ex-type culture CCF 6842). Sequence accessions: ITS – PX 523828, LSU - PX 591254, WGS - ERZ 28669458. Description. On YMA, after 7 days of incubation at 28 ° C, the culture is white, soft and slightly wrinkled. On MEA, under the same incubation conditions, the culture is white, dry and powdery. On YMA, after 21 days of cultivation, the colony is soft, with a flat undulate margin and a raised, rugose centre, cream in colour. On MEA, after 21 days of cultivation, the colony is cream-coloured, raised, with a flat, undulate margin and an elevated centre, slightly wrinkled, with a filamentous growth in the upper layer (Fig. 8 K). In both ME and YM media, after 7 days of incubation at 28 ° C, the cells are globose, oval to ovoidal (1.1–4.2 × 2.7–12 µm), some of them with a blunt end, and occur singly or in pairs. Short hyphae with blastoconidia occur (Figs 8 G, 8 H). Sediment and slight cloudiness are formed in both media. True hyphae with blastoconidia, arising from denticles, are formed on MEA after 7 days at 28 ° C (Fig. 6 I). Lipid particles of various shapes and sizes are formed after 21 days at 25 ° C (Fig. 6 J). No sexual reproduction is observed. Physiological and biochemical characteristics. Fermentation of glucose and d-xylose is absent. The following carbon compounds are assimilated: glucose, fructose, mannose, galactose, maltose, saccharose, raffinose, melezitose, d - xylose, l - arabinose, cellobiose, trehalose, soluble starch, melibiose, l-rhamnose, d - sorbose, d - ribose, salicin, xylitol, ribitol, d - mannitol, d - glucitol, erythritol, myo - inositol, ethanol, glycerol, n-acetyl- d - glucosamine, succinic acid, and citrate. The other carbon compounds - lactose, inulin, d - arabinose, methanol and dl-lactate- are not assimilated. The nitrogen compounds: ethylamine and n-acetyl- d - glucosamine are assimilated, whereas nitrate, nitrite, l-lysine, cadaverine, and creatinine are not assimilated. The urease reaction is negative. Starch-like polysaccharides are not produced. Growth in a vitamin-free medium, 10 % NaCl + 5 % glucose (w) and 50 % glucose is positive. Growth at 5 and 10 ° C is weak. Growth at a range from 20 ° C to 30 ° C is positive. Growth at 35 ° C is negative. Distribution. It is currently documented solely from the type locality in Slovakia. Further investigations are required to determine whether its distribution corresponds to the range of its insect vector, T. oxyurus. No identical or similar (≥ 90 %) sequences were found in the GlobalFungi database. Notes. Based on the phylogenomic and ITS- LSU rDNA analyses, it forms a lineage sister to S. mastotermitis (Fig. 4, 6).