Fulvoderma microporum Xue W. Wang & L.W. Zhou, sp. nov.
Index Fungorum number: IF 900291; Mycobank number: MB 900291; Facesoffungi number: FoF 14054; Figs. 1, 2
Etymology – microporum (Lat.) referring to the small pores.
Holotype – LWZ 20210626-12b (HMAS).
Diagnosis – Characterized by fulvous to snuff brown pileal surface, umber pore surface, small, circular pores, the absence of cystidia and cystidioles, and small, broadly ellipsoid to globose basidiospores.
Basidiomes annual, laterally stipitate, solitary or imbricate, without odor or taste when fresh, hard corky. Pilei projecting up to 7 cm long, 8 cm wide and 1 cm thick at base. Pileal surface fulvous to snuff brown, distinctly concentrically zonate, tuberculate and warty; margin acute, colour consistent with pileal surface, wavy. Pore surface umber, glancing; sterile margin cinnamon-buff, up to 5 mm wide; pores mostly circular, 7–8 per mm; dissepiments thin, entire. Context honey-yellow, hard corky, up to 7 mm thick. Tubes clay-buff, hard corky, up to 3 mm long. Stipe up to 3 cm long and 2.5 cm in diam.
Hyphal system monomitic; generative hyphae simple septate; tissue xanthochroic. Contextual hyphae pale yellowish to yellowish, thick-walled with a wide lumen, rarely branched, simple septate, interwoven, 5–6 µm in diam. Tramal hyphae hyaline, pale yellowish to yellowish, thick-walled with a narrow lumen, unbranched, simple septate, interwoven, 3–4 µm in diam. Hymenial setae dark brown, thick-walled with a narrow lumen, ventricose and apex sharp, 20–35× 7–7.5 µm. Cystidia and cystidioles absent. Basidia barrel-shaped to subclavate, simple septate with four sterigmata, 10 × 5–6 µm; basidioles in shape similar to basidia but slightly smaller. Basidiospores broadly ellipsoid to globose, with a big guttule, hyaline, thin-walled, IKI–, CB–, 4–4.5(–5)×3–3.5 µm, L=4.25 µm, W=3.25 µm, Q=1.29–1.31 (n=60/2).
Material examined – China, Jiangxi Province, Jiujiang, Bailudong Academy, ground under gymnosperm, 26 June 2021, L.W. Zhou, LWZ 20210626-12b (HMAS, holotype); ibid., LWZ 20210626-24b (HMAS).
GenBank numbers – LWZ 20210626-12b: ITS=OQ540896; LSU=OQ540854; LWZ 20210626-24b: ITS=OQ540897; LSU=OQ540855.
Notes – Fulvoderma microporum resembles the other two species of Fulvoderma, F. australe and F. scaurum, for their annual, sessile to laterally stipitate, solitary or imbricate basidiomes and yellowish brown pileal surface. However, F. australe has larger angular pores (5–6 per mm) and basidiospores (4.5–5.5×4–4.5 μm), and F. scaurum is also distinct by larger pores (4–5 per mm) and basidiospores (5–6×4–4.6 μm, Zhou et al. 2018). Moreover, F. microporum occupies a distinct lineage from F. australe and F. scaurum within Fulvoderma (Fig. 3).
Figure 1 – Basidiomes of Fulvoderma microporum (LWZ 20210626-12b, holotype)
Figure 2 – Microscopic structures of Fulvoderma microporum (LWZ 20210626-12b, holotype). a Basidiospores. b Basidia and basidioles. c Hymenial setae. d Hyphae from context. e Hyphae from trama. Scale bars: a=5 μm, b−e=10 μm
Figure 3 – Phylogram generated by the maximum likelihood algorithm based on combined nLSU and ITS sequence data is presented along with the bootstrap values and the Bayesian posterior probabilities above 50% and 0.8, respectively, at the nodes. Type specimens are in bold and the isolates of new species characterized are in blue