Sanguinoderma bambusae K. Y. Niu, S. M. Tang & Z. L. Luo, 2025

Sanguinoderma bambusae K. Y. Niu, S. M. Tang & Z. L. Luo sp. nov.

Figs 3 View Figure 3 , 5 c, d View Figure 5

Diagnosis.

Sanguinoderma bambusae differs from S. laceratum by having a dark gray and glabrous pileus, relatively small pores, dissepiments that remain intact when dry, centrally stipitate, slightly curved, grayish-orange to black stipe.

Etymology.

The epithet “ bambusae ” refers to its growth on the ground in bamboo forests.

Holotype.

China • Yunnan Province, Dehong Prefecture , Dendrocalamus spp. forest humus, alt. 1,593 m, 24.754404 ° N, 98.235173 ° E, Kai-Yang Niu, 6 July 2023, HKAS 144474 View Materials . GoogleMaps

Description.

Basidiomata annual, centrally stipitate, coriaceous to corky. Pileus umbelliform, up to 13.5 cm in diameter and 6 mm thick; pileus surface dark gray (# 575757) to black (# 000000), dull, glabrous, slightly dense, and radial fine wrinkles; margin dark gray (# 5 d 5 d 5 d), obtuse, entire, with sparse lacerated-like petal structures, slightly wavy and incurved when dry; Context up to 2 mm thick, homogeneous, slightly orange (# c 2 a 37 f), soft, and corky without black melanoid lines. Tubes up to 4 mm long, with the same color as the context, hard, and unstratified. Pores 6–9 per mm, oval to circular, grayish orange (# 756961) when fresh, becoming red when bruised and then quickly darkening; without discoloration, dissepiments remain intact when dry. Stipe up to 27 cm long, 8 mm in diameter, central, cylindrical, hollow, slightly curved, grayish orange (# 6 b 6252) to black (# 000000), and fibrous to woody.

Hyphal system trimitic with generative hyphae 3–6 μm in diameter, hyaline, thin-walled, and with clamp connections; skeletal hyphae 4–8 μm in diameter, pale yellow, thick-walled with a wide or narrow lumen to subsolid; binding hyphae 1–4 μm in diameter, pale yellow, flexuous, branched. All hyphae IKI – and CB +. Context darkened in KOH. Pileipellis trichoderm is a regular palisade, apical cells 5–7 × 20–32 μm, short clavate, and yellowish brown. Basidiospores broadly ellipsoid, light grey, IKI – and CB + with double and thin walls; exospore wall is smooth; endospore wall features conspicuous pillars, (10.1 –) 10.3–13.8 (– 14.4) × (8.6 –) 8.7–10.9 (– 11.6), L = 11.6 μm, W = 9.6 μm, Q = 1.21 (n = 40 / 2). Under SEM, exospore wall has regular and continuous reticulate protrusions. Cystidia narrowly cylindrical to narrowly clavate, hyaline, thin-walled, and 44–50 × 5–9 μm. Basidia barrel-shaped to widely clavate, hyaline, thin-walled, and 25–26 × 16–18 μm. Basidioles elongated ellipse to ellipse, hyaline, thin-walled, and 20–22 × 14–18 μm.

Additional specimens examined.

China • Yunnan Province, Dehong Prefecture , on Dendrocalamus spp. forest humus, alt. 1,702 m, 24.731679 ° N, 98.255132 ° E, Kai-Yang Niu, 6 July 2023, HKAS 144473 View Materials GoogleMaps .

Notes.

In multi-locus phylogenetic analysis, Sanguinoderma bambusae formed a sister clade with S. ovisporum K. Y. Niu, J. He & Z. L. Luo , and S. laceratum Y. F. Sun & B. K. Cui — all three species have been reported in Yunnan, China. Morphologically, Sanguinoderma bambusae differs from S. ovisporum ( Niu et al. 2024) and S. laceratum ( Sun et al. 2020) by its centrally stipitate, dark gray pileus and smaller pores (6–9 per mm) (Table 2 View Table 2 ).

Sanguinoderma dehongense K. Y. Niu, J. He & Z. L. Luo is morphologically similar to S. bambusae with an orange context and tubes, soft and corky without black melanoid lines, stipe length ( 21 cm), and slightly curved. However, S. dehongense differs by its larger pores (3–4 per mm), smaller basidia (8–11 × 9–13 μm), and basidiospores (9.3–10.8 × 8.4–9.8 μm) ( Niu et al. 2024) (Table 2 View Table 2 ).