Phaeoclavulina aurantilaeta P.T. Deng & P. Zhang, 2025

Phaeoclavulina aurantilaeta P.T. Deng & P. Zhang , sp. nov. ( Figs. 2–4 View FIGURE 2 View FIGURE 3 View FIGURE 4 )

MycoBank:856560

Diagnosis:—Differs from Phaeoclavulina cinnamomea by having orange with pale red tinge basidiomata, shorter basidiospores, and basidia.

Holotype:— CHINA, Hunan Province, Chenzhou County, 25°97′84″N, 113°71′78″E, elev. 1115m, 16 June 2024, P. Zhang ( MHHNU11750 , GenBank Accession number of ITS: PQ589930, GenBank Accession number of LSU: PQ579885 ).

Etymology:— aurantilatea , from the Latin aurantiacus and laetus, refers to the orange with a pale red tinge in the holotype.

Description:—Ramaroid, 40–65 mm tall, 35–55 mm broad, orange [5A7–8, zinc orange], pale red [6A7] with age. Stipe single or falsely fasciculate, 10–15 mm long, concolorous with branches, smooth, white mycelium at the base, not changing color on bruising. Branches dichotomous to polychotomous, divided two to four times, primary branches thick and in cross-section rounded; the diameter of terminal branches becoming short, dark reddish brown with age, bifurcation narrowly U-shaped. Apices acute, relatively short, dichotomous, concolorous with branches. Context whitish. Taste not recorded; odor not distinctive. Macro-chemical reactions: 10%FeCl 3: greenish; Melzer's reagent: negative; 10%KOH: leaches dull orange and pale red.

Basidiospores [60/3/2] (9.5–)10.0–11.5(12.0) × (4.8–)5.0–6.5(–6.8) μm [Q = 1.61–2.07(–2.16), Qm = 1.83 ± 0.13], elongate and sub-cylindrical, bend slightly at the end, thick-walled, pale yellow in 5%KOH, cyanophilic, with a distinct apiculus, surface coarse, echinulate, truncate (volcanic) spines 0.8–1.5 μm long, acute. Basidia 35–50 × 10–12 µm with four sterigmata 5–8 µm long, hyaline, clavate, clamp connections at base. Cystidia absent. Context hyphae in parallel arrangement, with clamp connections but not at every septum, thin-walled, tramal hyphae of branches 3.0–5.0 μm wide, sometimes flat to 7.0 μm wide.

Habit and distribution:—Solitary, growing on the soil in the mixed forest, basidiomata generally occur in early summer. Known only from the type region, Hunan Province, China.

Additional materials examined:— CHINA, Hunan Province, Chenzhou County, 25°91′65″N, 113°68′96″E, elev. 1050m, 21 September 2024, P. Zhang (MHHNU12213).