Cortinarius orientiprivignipallens Y. W. Yang, Y. Zhang & Q. Zhao 2025, sp. nov.

Cortinarius orientiprivignipallens Y.W. Yang, Y. Zhang & Q. Zhao, sp. nov. FIGURE 2 Chinese name: 东Ẇ小n丝DZā (dong fang xiao bai si mo jun) Index Fungorum number: IF904625 Etymology: orientiprivignipallens refers to the similarity of the new species to the European species C. privignipallens, which was collected from Orient. Diagnosis: This species morphologically resembles C. privignipallens, particularly evident in the presence of a light grey fibrillose texture on the pileus; however, it can be distinguished by the distinct brown remnants of the universal veil, larger basidiospores (8.5–10.0×6.0–7.5μm), and a higher Q value (1.40 ± 0.09). Holotype: CHINA, Yunnan Province, Lijiang City, details, XXXX, 26°37'54.32"N, 99°43'6.60"E, elev. 3,956 m, in Abies forest, 10 Aug. 2023, Ying Zhang 18 (KUN-HKAS 148598; GenBank: ITS PV682775; LSU PV682780). Description: Basidiomata medium to large-sized. Pileus 2–7 cm diam, conical to slightly hemispherical, expanding to plano-conical to nearly fully expanded and umbonate with age; surface initially covered with greyish white fibrillose, becoming glabrous with age, burnt sienna (7D8) to greyish ruby (12C3); hygrophanous; margin white, slightly radially striate; context 1–3 mm thick, greyish magenta (13D3). Lamellae emarginate, 3–5 mm broad, moderately crowded, first greyish red (9C4), later titian red (7D6); edges initially covered with greyish white (1B1) fibrillose, becoming very soft red with age. Stipe 5–10 × 0.5–0.8 cm (at the apex), cylindrical, usually tapering upwards, solid; surface initially covered with greyish white fibrillose; greyish violet (18B4) at the apex, transitioning to greyish white (1B1) below; becoming hollow or developing a spongy interior with maturity; base clavate to bulbous (bulb up to 1.5–2 cm); context violaceous (16C5) at the apex, transitioning to greyish red (11D4) below. Universal veil remnants brown (7D7), present at the pileus margin. Basal mycelium white. Odor not distinctive. Basidiospores [100/2/2] (8–)8.5–10(–10.5) × (5.5–)6–7.5(–8) μm [Q = (1.13–) 1.27–1.55 (–1.64), Q = 1.40 ± 0.09], broadly ellipsoid to ellipsoid, containing a single medium-sized oil droplet, light brown (5D4) to yellowish brown (5D8) in 10% KOH, finely verrucose, moderately dextrinoid in Melzer's reagent. Basidia 28–38.5×7.5–9 μm, clavate, colorless or greyish brown (5D3) with small granules, 4-spored. Lamellar trama hyphae 3–6 μm diam., smooth, colorless to greyish brown (5D3) in 10% KOH. Marginal elements somewhat inflated, (n=15) 18.5–25×7.5–11.5 μm, densely arranged. Pileipellis duplex: epicutis 40–55 μm thick, composed of tightly packed, pale yellow, elongated hyphae 4–6 μm diam.; hypocutis 180–230 μm thick, consisting of interwoven, cylindrical to elliptical, pale-yellow hyphae 18–32 μm diam. Stipe hyphae 8–12 μm diam, colorless, smooth. Clamp connections present. Habitat: — Scattered or gregarious on the ground in the Abies forest. Material examined:— CHINA, Yunnan Province, Lijiang City, 26°37'52.58"N, 99°43'25.49"E, elev. 3,857 m, in Abies forest, 9 Aug. 2023, Wang sa 8 (KUN-HKAS 148599; GenBank: ITS PV682774; LSU PV682779). Notes:— Cortinarius orientiprivignipallens is distinguished by its initially fibrillose pileus surface, exhibiting a greyish-white coloration that becomes glabrous as it matures; the stipe displays a greyish-violet hue at the apex, while remnants of the universal veil appear brown. Phylogenetic analyses indicate that C. orientiprivignipallens is classified within section Privignati, forming a sister lineage to C. privignipallens (Fig. 1). The Canadian and European lineages of C. privignipallens form a strongly supported yet short clade. Landry et al. (2021) documented a mere single base pair (bp) divergence between these two lineages. In contrast, sequence alignment of C. orientiprivignipallens with the aforementioned lineages revealed a substantial divergence of 12–13 bp, providing compelling evidence for recognizing C. orientiprivignipallens as a distinct new species. Morphologically, C. orientiprivignipallens may be confused with C. privignipallens. Both species exhibit a pileus and stipe that are initially adorned with a grayish-white fibrillose (Schmidt-Stohn et al. 2017). However, the context at the apex of the stipe in C. orientiprivignipallens is characterized by a slightly desaturated violet hue, which is absent in C. privignipallens. Additionally, the remnants of the universal veil exhibit contrasting colors, appearing brown in C. orientiprivignipallens and white in C. privignipallens; the basidiospores of C. orientiprivignipallens are larger, 8.5–10 × 6–7.5 μm, compared to 6.6–8.5 × 5.3–6.3 μm in C. privignipallens (Schmidt-Stohn et al. 2017).

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.