Tylopilus yangzhuliangii N.K. Zeng, Yi Wang, Xu Zhang & Zhui Li, 2022

Li, Zhui, Zhang, Xu, Jiang, Shuai, Ji, You-Dong, Wang, Yi & Zeng, Nian-Kai, 2022, Tylopilus yangzhuliangii (Boletaceae, Boletales), a new bolete from tropical China, Phytotaxa 543 (2), pp. 135-149 : 141-145

Tylopilus yangzhuliangii N.K. Zeng, Yi Wang, Xu Zhang & Zhui Li , sp. nov. ( Figs. 2 , 3 )

MycoBank: MB842386

Etymology:—Latin, ‘ yangzhuliangii ’ is named after the Chinese mycologist, Zhu L. Yang, in honor of his great contribution to mycology.

Diagnosis:—Characterized by very small basidiomes, a peacock blue to deep turquoise pileus, the hymenophore bruising reddish brown when injured, and a slightly interwoven trichodermium composed of uninflated hyphae forming the pileipellis.

Holotype:— CHINA. Hainan Provice: Yinggeling of Hainan Tropical Rainforest National Park , elev. 850 m, 7 May 2018, N. K. Zeng 3358 ( FHMU2930 ). GenBank accession number: 28 S = MW 826997 , ITS = MW 830253 , TEF1 = MW 925820 .

Description:— Basidiomes very small. Pileus 0.8–2 cm in diam, subhemispherical at first, then convex to applanate; margin curved downwards; surface dry, nearly glabrous, peacock blue (24D6–7) to deep turquoise (24F8); context about 0.7 cm thick in the center of the pileus, white, unchanging in color when injured. Hymenophore poroid, adnate or slightly depressed around apex of stipe; tubes about 0.6 cm in length, white (1A1), bruising reddish brown (7E8) slowly when injured; pores angular to almost round, about 0.3 cm in diam, white (1A1), turning reddish brown (7E8) slowly when injured. Stipe 3–3.6 × 0.3–0.6 cm, central, sub-cylindrical, solid, usually flexuous; surface white (1A1), bruising brownish (7E8) when injured; context white (1A1), unchanging in color when injured; basal mycelium white (1A1).

Basidia 14–37 × 8–10 μm, clavate, thin- to slightly thick-walled (up to 1 μm), 4-spored, colorless in KOH; sterigmata 2–4 μm in length. Basidiospores [120/6/2]8–10.5(–11) × 4.5–5.5(–6) μm, Q=1.58–2.00 (–2.10) μm, Qm=1.88 ± 0.12, subfusiform to ellipsoid, slightly thick-walled (up to 0.5 μm), pale yellowish brown to yellowish brown in KOH, smooth. Cheilocystidia 35–50 × 10–15 μm, subfusiform or fusiform, thin-walled, usually containing yellow to brownish yellow pigments. Pleurocystidia 40–60 × 13–17 μm, subfusiform or fusiform, usually containing yellow to brownish yellow pigments. Pileipellis a slightly interwoven trichoderm 50–160 μm thick, composed of hyphae yellowish in KOH, 2–7 μm wide, thin-walled; terminal cells 17–47 × 4–8 μm, sub-cylindrical. Pileal trama made up of hyphae 3–6 μm in diam, yellowish in KOH. Stipitipellis a hymeniderm 160–280 μm thick, composed of thin-walled, emergent hyphae with clavate, subclavate or subfusiform terminal cells (25–44 × 5–14 μm), yellow to yellowish brown in KOH. Stipe trama composed of 2–11 μm wide, cylindrical, thin-walled, yellow in KOH, parallel hyphae. Clamp connections absent in all tissues.

Habitat:—Gregarious on the ground in mixed forests of Castanopsis fissa (Champion ex Bentham) Rehder & E.H. Wilson and Pinus fenzeliana Hand. -Mzt.

Known distribution:—Southern China (Hainan Province).

Additional materials examined:— CHINA. Hainan Province: Yinggeling of Hainan Tropical Rainforest National Park , elev. 850 m, 7 May 2018, N. K. Zeng 3359 ( FHMU2921 ) .

Figures

FIGURE 2. Basidiomes of Tylopilus yangzhuliangii. (a from FHMU2930, holotype; b–c from FHMU2921). Photos by N.K. Zeng.

FIGURE 3. Microscopic features of Tylopilus yangzhuliangii (FHMU2930, holotype). a. Basidia. b. Basidiospores. c. Cheilocystidia. d. Pleurocystidia. e. Pileipellis. f. Stipitipellis. Bars=10 μm. Drawings by Y. Wang and X. Zhang.