Tricholoma aurantiophyllum L.P. Tang, H.Y. Huang, F.Q. Yu & R. Wang, 2024

Huang, Hong-Yan, Wang, Ran, Zhang, Wen-Hao, Yu, Fu-Qiang & Tang, Li-Ping, 2024, Phylogeny and taxonomic revision of Hygrophorus robustus (Hygrophoraceae, Agaricales) from southwestern China, Phytotaxa 664 (3), pp. 181-190 : 184-185

Tricholoma aurantiophyllum L.P. Tang, H.Y. Huang, F.Q. Yu & R. Wang , nom. nov. ( Figs. 2 , 3 ), non Tricholoma robustum (Alb. & Schwein.) Ricken (1914)

Chinese name: DZDz口®

Replaced synonym:— Hygrophorus robustus F.Q. Yu, Mycotaxon 100: 170 (2007)

McoBank:—MB 844179

Etymology:— “ aurantiophyllum ” refers to the brownish orange lamellae of this species. A replacement name is necessary as the epithet ‘ robustum ’ (Neuter form of ‘ robustus ’) is already taken in the genus Tricholoma as T. robustum (Alb. & Schwein. 1805: 147) Ricken (1914: 332 , Ricken 1914).

Holotype:— CHINA. Yunnan Province: Kunming City, Wujing Road, Wild Mushrooms Market , elev. unknown, 23 July 2005, F. Q. Yu 1271 (KUN-HKAS 49785!, GenBank Acc. No.: ITS = ON615053 , LSU = ON615050 ).

Description:— Basidiomata medium to large. Pileus 6–13 cm diam., hemispherical, convex to broadly convex, pale orange to pale ochre (5A4–5) when young, becoming tawny (5B4–5), ochraceous to raw umber (4B6–7) in age or when dry, surface glabrous when moist, clothed with an appressed fine fibrillose or radially streaks when dry; context up to 1.5 cm, thick, white to cream (5A1–2). Lamellae up to 1.2 cm wide, adnate, sinuate or arcuate, subdistant, 45–75 pieces of complete lamellae/cap, pale orange to salmon buff (5A3–7), tawny (5B6–7), slightly darkened when mature, concolorous with pileus or even darker, with some short gills or lamellulae. Stipe 8–20 cm long, 1.8–4 cm diam., cylindrical, tapered toward the base, off-white (5A1–2), surface covered with concolorous appressed fibrous scale; context solid, white to cream (5A1–2). Odor pleasant, of freshly husked corn mixed with the aroma reminiscent of Tricholoma matsutake . Taste mild.

Basidiospores [70/4/4] 8–10 (–11.5) × 5–6.8 μm, Q = 1.33–1.73 (–1.83), Q m = 1.55 ± 0.11, ovoid to ellipsoid, occasionally elongate, smooth under the light microscope, thin-walled, hyaline, non-amyloid. Basidia 44–65 × (9–) 10–12 (–13) μm, clavate, thin-walled, predominantly 2- or 4-spored, occasionally 1-spored; sterigmata up to 11 μm in length. Hymenophoral trama regular, arranged in parallel, made up of cylindrical hyphae 3–10 μm diam., thin-walled, colorless and hyaline. Pileipellis an ixocutis to cutis, consisting of narrow hyphae 3–8 μm diam., thin-walled, smooth under the light microscope, often with pale yellowish brown intracellular pigment. Pileitrama made up of hyphae 4–17 μm diam., thin-walled, dense, parallel. Stipitipellis a cutis, composed of hyphae 4–8 μm diam. Stipititrama made up of hyphae 5–15 μm diam., thin-walled, arranged in parallel. Clamp connections absent in all tissues.

Habit and habitat:—Solitary or scattered under Castanopsis delavayi Franch or Quercus guyavifolia H. Léveillé ; elev. 2,300 –3,240 m; appearing in summer and autumn (July–October).

Distribution:—Currently known in Yunnan Province (Kunming city, Fumin, Nanhua, Yaoan, Yulong Naxi Autonomous four counties) elev. 2,300 –3,240 m.

Other material examined:— CHINA. Yunnan Province: Chuxiong City ( K ẽḿ), Zixi Mountain ( ḦNJƜ), Camellia Garden, 24°59ʹ96ʺN, 101º25ʹ2ʺE, elev. 2,363 m, 27 July 2005, F. Q. Yu 1283 (KUN-HKAS 49786!) ; Fumin County (ãk县), Wild Mushrooms Market , elev. unknown, 5 September 2019, R. Wang rfm-302 (KUN-HKAS 106771!, GenBank Acc. No.: ITS = MT902148 , LSU = ON615051 ) ; Nanhua County (南华县), Majie Town ( Ḷm ª), 24°53ʹ36ʺN, 100º48ʹ11ʺE, elev. about 2,330 m, 24 August 2015, J. W. Liu 396 ; ibid., 9 August 2017, J. W. Liu 776 ; Nanhua County (南华县), Nanhua Wild Mushrooms Market (南华Dffldzḿ场), elev. unknown, 2 October 2019, J. W. Liu rcx-725 (KUN-HKAS 106772!) ; Yaoan County (姚⁂县), Wild Mushrooms Market , elev. unknown, 24 August 1998, X. H. Wang 627 (KUN-HKAS 32908!, GenBank Acc. No.: ITS = ON615052 ) ; Yulong Naxi Autonomous County (ŀfiaeffnà县), Lijiang Alpine Botanical Garden (丽flẠƜüū园), 27°0′22″N, 100°11′18″E, elev. 3,240 m, 16 September 2019, J. W. Liu LJ 01863 (KUN-HKAS 106773!, GenBank Acc. No.: ITS = MT902149 ), J. W. Liu LJ 01864 (KUN-HKAS 106774!, GenBank Acc. No.: ITS = MT902150 ) .

Figures

FIGURE 2. Basidiomata of Tricholoma aurantiophyllum. a from KUN-HKAS 106771; b from KUN-HKAS 106773; c from KUN-HKAS 49785 (holotype). d from J.W. Liu 396; e from J.W. Liu 776; f from KUN-HKAS 49786 (a photo by R. Wang; b, d, e photos by J.W. Liu; c, f photo by F.Q. Yu).

FIGURE 3. Microscopic features of Tricholoma aurantiophyllum. a–b Hymenophoral trama; c–d Basidiospores; e–f Basidia. a, c, e from KUN-HKAS 49785 (holotype); b, d, f from KUN-HKAS 106773 (recent collection). Bars: a–b = 100 μm; c–f = 10 μm (Photos by H.Y. Huang).