Cudonia cangshanensis K.Y. Niu, Z.L. Luo & S.M. Tang, 2025

Cudonia cangshanensis K.Y. Niu, Z.L. Luo & S.M. Tang , sp. nov. (Fig. 3)

Fungal Names:—FN 572684

Diagnosis: — Cudonia cangshanensis differs from other species by its stipe long clavate, slightly swollen at the base, clearly striated longitudinally at the upper part, hymenium is relatively thick ( x = 162 μm), gradually fading downward, ascospores are relatively large ( x = 67 × 3.0 μm).

Etymology: —The epithet “ cangshanensis ” refers to the fungus was collected from Cangshan Mountain in Dali Bai Autonomous Prefecture.

Holotype: — CHINA, Yunnan Province, Dali Bai Autonomous Prefecture, Cangshan mountain, surface of the coniferous forest soil, 2,049 m, Song-Ming Tang and Kai-Yang Niu , 27 October 2024 ( HKAS 147014 View Materials , holotype!).

Description: —Ascomata gregarious, Apothecia 2–5 cm in height, up to about 1 cm diameter. Pileus faint yellow (#e6dea9), long saddle shape, smooth, up to 0.5–1 cm diameter, with a slightly depressed center and strong inward curl margin, crisp when dry. Stipe color yellowish brown to brown (#A2866F), long clavate, with clearly striated longitudinally at the upper part, gradually becoming thicker from top to bottom, up to 3–5 cm long.

Hymenium 136–183 μm ( x = 162 μm, n = 9) thick, surface smooth, hyaline. Medullary excipulum 311–521 μm ( x = 440 μm, n = 6), thick, hyaline, thin-walled, textura porrecta hyphae 3.4–8.6 μm ( x = 6.1 μm, n = 23) diameter. Ectal excipulum 51–105 μm ( x = 69 μm, n = 5) thick, hyaline, thick-walled, with textura angularis, 14.1–38.8 × 7.5– 21.7 μm ( x = 26.2 × 13.9 μm, n = 16), irregular arrangement, irregular strip-like to spherical. Stipitipellis 30–87 μm ( x = 50 μm, n = 17) thick, uneven thickness, with thin-walled cells of textura epidermoidea, 7.8–23.6 × 2.2–6.0 μm ( x = 14.0 × 3.6 μm, n = 16). Paraphyses 1.6–3.7 μm ( x = 2.3 μm, n = 13) in diameter, hyaline, long and narrow strips, unbranched, aseptate, rounded ends. Asci 77–148 × 8.2–15.8 μm ( x = 120 × 12.3 μm, n = 50), 8-spored, hyaline, inamyloid, inoperculate, clavate to narrowly clavate, pleurorhynchous, prototunicate, gradually narrows towards the base. Ascospores 52–82 × 2.1–4.3 μm ( x = 67 × 3.0 μm, n = 45), hyaline, uniseriate, clavate, thin-walled, drop-shaped contents, aseptate, with an overall gelatinous layer and prominent gelatinous caps. Ascoconidia 2.7–4.1 × 1.9–2.3 μm ( x = 3.3 × 2.3 μm, n = 26), hyaline, broadly ellipsoid to lacrymoid, sometimes replacing the ascospores and filling the asci.

Additional specimen examined:— CHINA, Yunnan Province, Dali Bai Autonomous Prefecture, Cangshan mountain, surface of the coniferous forest soil, 2,122 m, Song-Ming Tang and Kai-Yang Niu, 27 October 2024 (HKAS 147015).

Notes: —In the phylogenetic analysis, Cudonia cangshanensis and C.lutea form sister clades.Sequence comparison for the ITS region between C. cangshanensis (HKAS 147014 holotype) and C. lutea (Z.W. Ge 608) showed a 3.77% (16/424 bp, excluding gaps) base pair difference. Cudonia lutea differs from C. cangshanensis by pileus pileate, fleshcolor to orange-buff, narrow ascospores (2 μm), without ascoconidia.

In morphology, Cudonia cangshanensis and C. yunnanensis share similar characteristics in the pileus are both saddle-shaped, with brown stipes that slightly swollen at the base. However, there are distinct differences in microscopic morphology, the hymenium ( x = 154 µm), asci ( x = 112 × 10.8 µm), ascospores ( x = 55 × 2.2 µm), and paraphyses ( x = 2.1 µm) of C. yunnanensi s are smaller than those of C. cangshanensis ( TABLE 2).