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

Phaeoclavulina jilinensis P. Zhang & W. H. Liu sp. nov. Fig. 4 Diagnosis. Differs from other Phaeoclavulina species by the citrine fruiting body and only known from Jilin Province, China. Type. China • Jilin Province, Fusong County, 42 ° 57 ' 66 " N, 127 ° 97 ' 68 " E, 665 m asl., 26 August 2020, leg. P. Zhang (holotype MHHNU 10504). Etymology. jilinensis (Latin), referring to the currently known distribution of the species in Jilin Province, China. Basidiomata. Ramaroid, 35–90 mm tall, 15–50 mm broad, pinecone yellow [2 A 3–5], pale lemon-yellow [4 A 5–6] with age. Stipe single or falsely fasciculate, 25–35 mm long, concolorous with branches when young, ochraceous with age, smooth, many mycelia at base, not changing color on bruising. Branches dichotomous to polychotomous, divided three to five times, primary branches thick and in cross-section rounded; terminal branches short and becoming flat, bifurcation narrowly V-shaped. Apices acute, rather short, dichotomous, concolorous with branches. Context whitish, fleshy. Taste and odor, and macrochemical reactions not recorded. Micromorphology. Context hyphae compact, 3–7 μm wide, cylindric, inflated to 11 μm wide, clamp connections present, thin-walled, smooth, hyaline. Basidia approximately 20–36 × 5–7 µm with four sterigmata 3–5 µm long, hyaline, clavate or subclavate, with clamp connection at base. Cystidia absent. Basidiospores [60 / 3 / 3] (5.5) 6.0–8.0 (8.5) × (2.8) 3.0–5.0 (5.5) μm [Q = 1.67–2.40, Q m = 1.96 ± 0.16], elongate-ellipsoid, thick-walled, pale yellow in KOH, cyanophilic, surface coarse, with short but distinct spines, spines 0.8–1.5 μm long, strongly cyanophilous, hilar appendage distinct. Habit and distribution. Solitary on the humus layer under mixed forest; basidiomata generally occur in summer. Known only from the type locality in China. Additional materials examined. • Jilin Province, Yanbian Korean Autonomous Prefecture, Changbai Mountain Academy of Sciences, 42 ° 40 ' 51 " N, 128 ° 11 ' 48 " E, 896 m asl., 6 August 2017, MHHNU 9149 • Jilin Province, Yanbian Korean Autonomous Prefecture, Changbai Mountain, 42 ° 22 ' 61 " N, 128 ° 19 ' 42 " E, 950 m asl., 7 August 2017, MHHNU 9164. Comments. In the present phylogenetic analysis, P. jilinensis was closely related to accessions of P. flaccida and P. roellinii. Phaeoclavulina roellinii has an ochraceous to watery ochre-brown fruiting body and P. flaccida has a beige fruiting body. Thus, these species cannot be distinguished by color alone, but by other characters. Phaeoclavulina roellinii has long and narrowly clavate basidia (38–70 × 5–7 (8) μm), whereas P. jilinensis has relatively short basidia (20–36 × 5–7 µm). In addition, P. roellinii has abundant stellate crystals adhering to the hyphae, but we have not observed this character in P. jilinensis. The color of the fruiting body, sparse branches, and relatively longer basidia (38–45 × 5.5–6.5 vs. 20–36 × 5–7 μm) distinguish P. flaccida from P. jilinensis.