Strobilomyces anthracinus

Strobilomyces anthracinus L.H. Han, J. Xu & Zhu L. Yang.

Index Fungorum number: IF 824854; MycoBank number: MB 104808

Basidiomes tiny to small. Pileus 25–50 mm diam, at first subhemispherical or convex, then applanate, dry, covered with charcoal black (17F2–8) to black (17F1), more or less erect pyramidal scales, 3–5 mm high, 3–5 mm diam at base, exposing dirty white (1B1) subpellis when breaking up; margin partially appendiculate with triangular fragments of thick floccose veil remnants concolorous with pileal surface; context white (8A1), quickly changing to rusty red (9C4) then black (10E1) on exposure. Tubes adnexed to narrowly adnate, white (6A1) then smoky grey (8C1); hymenophoral pores angular, small, 0.5–1 mm diam; pores and tubes concolorous, whitish (14A1) then fuscous (12D3), immediately staining rusty red (11D4) then black (17F8) on exposure. Stipe 50–80 mm long, 4–10 mm diam, subcylindrical or slightly tapering downwards; surface poroid reticulate with elongate meshes at apex, covered with thin fluffy floss, evenly distributed and projecting 1–2 mm from surface of stem, concolorous with pileus; context white (8A1), discolouration similar to that of tubes; annulus or annular zone absent; basal mycelium grey-white (6B1).

Basidiospores [60/3/3] (7.5–)8.5–10 × 6.5–8(–9) μm (Q = 1.2–1.41(–1.5), Qm = 1.32 ± 0.05) excluding ornamentation, broad ellipsoid to ellipsoid, dark brown (7D5), completely reticulate with meshes 2–3.5 μm diam and 1–1.5 μm high; apiculus 0.5 μm long. Basidia 35–45 × 10–16 μm, narrowly clavate to clavate, 4-spored; sterigmata 4–6 μm long. Hymenophoral trama boletoid; hyphae cylindrical, 6–11 μm wide. Cheilocystidia 48–70 × 14–25 μm, abundant, narrowly lageniform to narrowly conical, thin-walled, hyaline

or with dark brown plasmatic pigment. Pleurocystidia 41–65 × 13–18 μm, numerous, narrowly lageniform to conical, thin-walled. Pileipellis an intricate trichodermium, composed of 4–16 μm wide cylindric to submoniliform hyphae; loosely interwoven in clusters, with short attenuate terminal cells; cell wall dark brown (5E8), more or less thickened (< 1 μm).

Pileal trama composed of 4–12 μm wide interwoven hyphae. Hyphae of scales on stipe similar to those of pileus. Stipe trama composed of 3–10 μm wide cylindrical hyphae. Clamp connections absent.

Habitat & Distribution: Solitary or scattered on soil in forests dominated by Lithocarpus spp.; currently recorded from subtropical China.

Holotype: CHINA, Yunnan Province, Dali City, Nanjian County, Ailao Mountain Nature Reserve, 2580 m elev., 7 Aug. 2014, Q. Cai 1271 (HKAS 83740). Additional specimens examined. China, Yunnan Province, Puer City, Jingdong County, the Ailaoshan Station for Subtropical Forest Ecosystem Studies in Yunnan, 1450 m elev., 18 July 2007, Y.C. Li 885 (HKAS 52570); Yunnan Province, Baoshan City, Tengchong County, Gaoligongshan, 2100 m

elev., 9 Aug. 2011, B. Feng 1052 (HKAS 74532).

Fig. 1 Phylogeny inferred from four-locus dataset (RPB1- RPB2-TEF1-COX3), with branch lengths based on the Maximum Likelihood analysis. Only MLB over 70 % and BPP over 0.95 are given in the tree. Bold black and red branches represented independent evolutionary lineages that were well supported by at least one locus and not contradicted by any other locus. Bold red branches showed phylogenetic species. Eight newly described species are indicated in black bold letters. The Roman numerals (I, II, III and IV) indicated the four major clades of Strobilomyces. The two sections are displayed on the right of the phylogram.