Gerhardtia sinensis T.H. Li, T. Li, C.Q. Wang & W.Q. Deng, 2017

Li, Ting, Li, Taihui, Wang, Chaoqun, Deng, Wangqiu & Song, Bin, 2017, Gerhardtia sinensis (Agaricales, Lyophyllaceae), a new species and a newly recorded genus for China, Phytotaxa 332 (2), pp. 172-180 : 173-176

Gerhardtia sinensis T.H. Li, T. Li, C.Q. Wang & W.Q. Deng , sp. nov. Figs. 1–3

MycoBank: MB 819692

Diagnosis:—Differs from G. highlandensis (Hesler & A.H. Sm.) Consiglio & Contu (2004: 158) in having white to yellowish pileus with faint striae, more distant, intervenose lamellae, more lamellulae between two complete lamellae, and slightly larger basidiospores measuring (4.7–)5.2–6.2(–6.6) × (2.5–)3.0–3.4(–3.8) μm.

Etymology:—The epithet “ sinensis ” refers to the type locality in China.

Typification:— CHINA. Guangdong Province, Zhaoqing, Dinghushan Biosphere Reserve , at 112°34′ E, 23°10′ N ; 8 August 2010, coll. Chunying Deng & Taihui Li (Holotype, GDGM 29981 ) .

Description:— Basidiomata small to medium. Pileus 32–56 mm broad, convex at first, expanding to plano-convex or applanate, depressed over disc when matured, sometimes slightly broadly umbonate or umbilicate at centre; margin involute when young, expanding to inflexed or at times uplifted in places when mature, sometimes flexuous or even somewhat lobed; surface nearly white, yellowish white to pale yellow (1A2–3, 3A3) at disc, snow white, satin white to yellowish white (1A1, 2A1–2, 3A2) near margin, dry, dull, somewhat hygrophanous with moisture loss, glabrous, usually with faint to moderately obvious striation; context 2.5–4.5 mm thick at stipe, less than 1 mm thick at near pileus margin, white to yellowish white (2A1–2), unchanged when cut or injured. Lamellae adnate to slightly sinuate, subdistant or close to subdistant, with 24–32 complete lamellae and 5–8 lamellulae of different lengths between two complete lamellae, 4–7 mm broad, concolorous with pileus to somewhat yellowish white (1A2–3, 2A2–3), slightly intervenose, not or occasionally forked; edge entire or eroded, concolorous. Stipe 20–60 × 5–12 mm, central or slightly eccentric, cylindrical to subcylindrical, often curved, white to milk white (1A1–2) or yellowish white (2A2), glabrous to finely tomentose, often tomentose at base, dry, somewhat hollow; stipe context white, yellowish white to similar to pileus colour, unchanged when cut or injured. Odour and taste not distinctive.

Basidiospores [50/5/5] (4.7–)5.2–6.2(–6.6) × (2.5–)3.0–3.4(–3.8) μm, [Q = (1.73–)1.81–1.86(–1.93), Q m = 1.84 ± 0.10, elongate-subellipsoid to oblong, thin-walled, guttulate, smooth under light microscope but slightly undulate and with some slightly angled at the distal end under SEM ( Fig. 2f ), cyanophilous, inamyloid; apiculus small, about 0.5

μm long. Basidia 26–32 × 5–7 μm, narrowly clavate or cylindrical, thin-walled, with cyanophilous and siderophilous granulations, hyaline in H 2 O and 5% KOH, 4-spored, with sterigmata up to 2–3 μm long, clampless; subhymenium thin, with ramose hyphae. Hymenophoral trama composed of regular, densely parallel hyaline hyphae 4–9 μm wide.

Cheilocystidia and pleurocystidia not observed or absent. Pileipellis 85–100 μm thick, a tightly bound cutis, composed of parallel hyphae; hyphae 4–7 μm wide, hyaline, thin-walled. Clamp connections absent.

Known distribution:—Known only from Guangdong and Guangxi provinces in southern China.

Habit and habitat:—Scattered on soil, in broad-leaved forests or coniferous and broad-leaved mixed forests dominated by Castanopsis chinensis (Spreng.) Hance , Litsea pungens Hemsl. , Schima superba Gardner & Champ and

Pinus massoniana Lamb. , July to September.

Additional specimens examined:— CHINA. Guangdong Province, Zhaoqing, Dinghushan Biosphere Reserve, at

112°33′ E, 23°10′ N, 9 July 2012, coll. Taihui Li & Ming Zhang ( GDGM 42435 ) ; Shaoguan, Chebaling National Nature

Reserve, at 114°16′ E, 24°43′ N, 3 September 2013, coll. Chaoqun Wang ( GDGM 45221 ) ; Guangzhou, Baiyunshan

Mountain, at 113°17′ E, 23°12′ N, 8 July 2016, coll. Yaheng Shen ( GDGM 46394 ) ; Guangxi Province, Qinzhou,

Fengliangshan Mountain, at 109°15′ E, 22°19′ N, 13 July 2012, coll. Ming Zhang (GDGM 42158).

Figures

FIGURE 1. Gerhardtia sinensis. a. Basidiomata of GDGM 29981 (holotype) b. Basidiomata of GDGM 46394 c. Basidiomata of GDGM 42158 d. Basidiomata of GDGM 45221 Scale bars: a–d = 2 cm. Photos by: Ting Li & Chaoqun Wang.

FIGURE 2. Gerhardtia sinensis. a. Cyanophilous bodies in basidia of GDGM 29981 (holotype). b. Cyanophilic basidiospores of GDGM 29981. c–d. Basidiospores of GDGM 29981 under SEM. e–f. Basidiospores of GDGM 46393 under SEM. Scale bars: a–b = 10 μm; c = 2 μm; d–f = 1 μm. Photos by: Ting Li.

FIGURE 3. Microscopic features of Gerhardtia sinensis (GDGM 29981, holotype). a. Basidiospores. b. Basidia. c. Pileipellis. Scale bars: a–c 10 μm. Drawings by: Ting Li.