Suillus zangii R. Zhang, X. F. Shi, G. M. Mueller & P. G. Liu, 2025

Shi, Xiaofei, Zhang, Shiru, Mueller, Gregory M., Liu, Peigui, Yu, Fuqiang & Senanayake, Indunil C., 2025, A subgeneric revision of the genus Suillus (Suillaceae, Boletales) and novel taxa from Eastern Asia based on morphology and multigene phylogenies, IMA Fungus 16, pp. e 144260-e 144260 : e144260-

Suillus zangii R. Zhang, X. F. Shi, G. M. Mueller & P. G. Liu sp. nov.

Figs 12 , 13

Etymology.

The species epithet honors Chinese mycologist Mu Zang.

Diagnosis.

The basal stipe context turns greenish blue always when exposed.

Typification.

China: • Yunnan Province, Diqing Tibetan Autonomous Prefecture, Shangri-la town, Nixi xiang (28°02'46.19"N, 99°30'16.41"E, alt. 3086 m), 17 September 2010, Xiaofei Shi, Shi 703 (holotype, HKAS 63254 ) .

GenBank.

ITS = KU 721321 ; LSU = KU 721726 ; TEFα- 1 = KU 852220 .

Morphology.

Pileus hemispherical to convex or flat, 3–8 cm diameter, surface viscid to glutinous in moist, glabrous, with amorphous brown cinnamon (6 D 5 to 6 D 7) color dots or patches over brownish yellow (5 B 4) background. Hymenophore adnate to subdecurrent, golden yellow (4 A 6, 4 A 7). Pores 1 to 2 per mm, angular. Tubes 4–6 mm deep, concolorous with pore surface. Stipe 5–8 × 1.5–2 cm, equal, solid, no veil, background color pallid yellow (3 A 4, 3 A 5), more yellowish towards the tube. Covered all over with glandular dots that are in streaks, brown (5 E 6) dots at apex, reddish brown (6 D 3) at the base. Mycelia white. Context yellowish white to yellow (3 A 3, 3 A 4) in pileus and stipe. Change color immediately in lower part of the stipe to greenish blue (25 A 5, 25 B 5) when cut. Spore print unknown. Odor and taste indistinctive.

Basidiospores [80 / 2 / 2] (8.5) 9.5–10.0 × 4.0–5.0 μm, Q = 1.90–2.38, Q sd = 2.14 ± 0.13, smooth, oblong in face view, narrowly inequilateral with a hilar appendage in profile view, brown or ochraceous in KOH, tawny yellow in Melzer’s. Basidia 4 - spored, clavate, bulbous top, 24.0–30.0 × 7.0–8.5 μm, hyaline yellow or brown in KOH, tawny yellow in Melzer’s. Hymenophoral trama divergent, wrinkled, thin-walled, hyaline and mostly 5–7 μm, up to 13 μm. Pleuro- and Cheilocystidia in fascicles, abundant, clavate, content brown or hyaline, surrounded by brown amorphous materials in KOH, up to 80 μm long. Caulocystidia abundant in all part of the stipe, morphologically similar with pleuro- and cheilocystidia, encrusted by brown pigments in KOH, up to 90 μm long. Pileipellis an ixocutis, hyphae densely encrusted with ochraceous granules, scattered in glue, most 3–10 μm, up to 13 μm wide. Stipitipellis mostly composed of interwoven hyphae, covered by brown amorphogous pigments, about 3–10 μm wide. Context trama hyaline, smooth, thin-walled, interwoven, similar for pileus and stipe, mostly 3–30 μm, up to 40 μm wide at stipe base. Clamp connections absent.

Habitat.

Solitary to scattered, in association with Pinus armandii .

Known distribution.

Currently only known from Shangri-la town in Yunnan Province, China.

Specimens examined.

China: • Yunnan Province, Diqing Tibetan Autonomous Prefecture, Shangri-la Town, Nixi Xiang (28°03'03.73"N, 99°29'48.80"E, alt. 3035 m), 17 September 2010, Xiaofei Shi, Shi 701 ( HKAS 63237 ) ; • ibid Shi 702 ( HKAS 63238 ) .

Notes.

This new species is sister with Suillus marginielevatus and S. indicus ( Sarwar et al. 2015; Verma and Reddy 2015). Geographic ranges and host associations can help separate Suillus zangii from the other two. Unlike Suillus zangii and Suillus marginielevatus , S. indicus has a white and membranous ring on the stipe, appendiculated cap margin, and no glandular dots. Also, Suillus indicus and S. marginielevatus are both in association with Pinus wallichiana . So it would be interesting to know, excluding observational errors, reasons for the presence or absence of veil and glandular dots not conserved among closely related species.

Figures

Figure 12. Basidiomata of Suillus zangii (holotype, HKAS 63254). Scale bar: 5 cm.

Figure 13. Suillus zangii (holotype, HKAS 63254). a Basidiospores; b Cheilocystidia; c Hymenium with basidia; d Pileipellis (mature specimens). Scale bars: 5 μm (a); 20 μm (b – d).