Phaeoclavulina bicolor P. Zhang & W. H. Liu 2024, sp. nov.

Phaeoclavulina bicolor P. Zhang & W. H. Liu sp. nov. Fig. 2 Diagnosis. Differs from other Phaeoclavulina species by the yellowish white apex. Type. China • Hainan Province, Jianfengling National Forest Park, 18 ° 74 ' 21 " N, 108 ° 84 ' 81 " E, 986 m asl., 30 July 2021, leg. P. Zhang (holotype MHHNU 10702). Etymology. bicolor (Latin), referring to the different color of the branches and branch tips. Basidiomata. Coralloid, 60–90 mm tall, 30–45 mm broad, light grayish brown when young [6 D 3–4], dark brown in age [6 E 5–7]. Stipe single, 10–20 mm long, white mycelia at the base. Branches sparse, branching from the base, dichotomous to polychotomous, divided two to three times, internodes becoming gradually shorter, terminal branches short and not flat, in cross-section rounded, axils V-shaped. Tips short and blunt, yellowish white [2 A 2–4] or pale white [1 A 1–2]. Context white, fleshy. Taste and odor, and macrochemical reactions not recorded. Micromorphology. Context hyphae in parallel arrangement, 3–4 µm wide, cylindric, inflated, with clamp connections but not at every septum, thin-walled, smooth, hyaline. Basidia approximately 40–50 × 5–8 µm with two sterigmata 5–6 µm long, hyaline, clavate, with clamp connection at base. Cystidia absent. Basidiospores [60 / 3 / 3] (7.6) 8–10 (10.5) × (3.8) 4–6 (6.5) µm [Q = 1.70–2.20, Q m = 1.97 ± 0.18], long-ellipsoid or cylindrical, slightly thick-walled, pale yellow in KOH, cyanophilic, surface coarse, echinulate, spines 0.6–1.0 μm long, acute; hilar appendage acuminate. Additional materials examined. • Hainan Province, Jianfengling National Forest Park, 18 ° 74 ' 32 " N, 108 ° 84 ' 76 " E, 978 m asl., 30 July 2021, MHHNU 10703. Habit and distribution. Solitary, growing on the soil of broad-leaved forest in tropical rain forest; basidiomata occur in summer. Known only from the type locality in China. Comments. Phaeoclavulina bicolor is distinguished from other species of Phaeoclavulina by the yellowish white branch tips, and the mainly grayish brown to dark brown basidiomata. Phaeoclavulina subdecurrens (Coker) Franchi & M. Marchetti also has basidiomata with a different color at the tips, but in P. subdecurrens the branch tips are pale violet to off white. Phaeoclavulina aeruginea has unique copper-green branch tips and has relatively larger spores than P. bicolor (13–16 × 8–9 μm vs. 8–10 × 4–6 μm). In the field, P. cyanocephala has relatively larger basidiomata (8–18 × 2–7 cm) and is distributed worldwide, whereas in P. bicolor the basidiomata is 6–9 cm tall, 3–4.5 cm broad, and the species is presently known only from Hainan Province in China.