Rossbeevera bispora (B.C. Zhang & Y.N. Yu) T. Lebel & Orihara, Fungal Diversity 52(1): 58 (2012)

Hosen, Md. Iqbal, Zhong, Xiang-Jing, Gates, Genevieve, Orihara, Takamichi & Li, Tai-Hui, 2019, Type studies of Rossbeeverabispora, and a new species of Rossbeevera from south China, MycoKeys 51, pp. 15-28 : 18-19

Rossbeevera bispora (B.C. Zhang & Y.N. Yu) T. Lebel & Orihara, Fungal Diversity 52(1): 58 (2012) Figs 2, 3, 6a, b

≡ Chamonixia bispora B.C. Zhang & Y.N. Yu, Mycotaxon 35(2): 278 (1989).

Description.

Basidiomata hypogeous, 25-45 mm broad, 20-30 mm high, small, globose to subglobose, napiform, sometimes deformed or reniform, fleshy when fresh, firm when dry. Pileus thin, surface glabrous to slightly velvety in some cases, shiny, sometimes alveolate or cracking with age, dull white, grayish white to grayish brown, whitish at the lower portion, turning blue to deep blue when touched or injured or when mature, occasionally basal part covered with yellowish white mycelia. Hymenophore off-white, white to dull white when young, blue to dark blue immediately when cut or injured, fleshy, soft and smooth, composed of minute, irregular locules, becoming partially collapsed with many small empty chambers when dried. Stipe absent. Sterile base present but reduced, white, dull white to grayish white, somewhat dendroid or as a small basal pad or rhizomorph. Odor and taste not recorded.

Basidiospores [80/4/4] 16-21 × 9-11.5 μm [mean 18.55 × 10.58 μm, Q = 1.63 –1.83(– 1.90), Qm = 1.75 ± 0.11], fusoid, ornamented with 4-longitudinal ridges (star-shaped in cross section), inamyloid, brown to dark brown in KOH and H2O, thick-walled up to 2 μm thick, hilar appendages 1-3 μm long. Basidia 12-25 × 5-8 μm, narrowly clavate to cylindro- clavate, hyaline to pale yellow, usually 2-spored, occasionally 1-spored. Hymenial cystidia absent. Hymenium developed when immature but collapsed at maturity, hyaline to pale yellowish; subhymenium not developed. Hymenophoral trama 60-160 μm wide, subgelatinous, composed of hyaline, cylindrical, loosely interwoven to parallel, frequently branched, thin-walled, cylindrical hyphae 2-5 μm wide. Pileipellis a repent cutis, terminal cells short, clavate to cylindro-clavate, yellowish brown to brownish pigmented, smooth, thin-walled. Clamp connections absent in all tissues.

Habit and habitat.

Solitary or in small groups beneath or on the ground, hypogeous or partially epigeous in a subtropical evergreen broad-leaved forest, putatively associated with Castanopsis fissa Rehder & E.H.Wilson, C. chinensis (Spreng.) Hance, C. fabri Hance and Schima superba Gardner & Champ.

Known distribution.

Currently known from south China (Guangdong Province: (Baiyunshan Mountain, Dinghushan Nature Reserve and Tianluhu Park).

Specimens examined.

CHINA. Guangdong Province, Zhaoqing City, Dinghushan Nature Reserve, 13 October 1982, You-Zao Wang, Wan-Ling Zhen, Jinag-Qing Li (GDGM 5688, holotype); 7 March 2013, Karl (GDGM 45612 and GDGM 45639); Baiyun Mountain, 7 April 2017, Yong He (GDGM 46631); Tianluhu Park, 21 March 2018, Tai-Hui Li, Chenghua Zhang, Xishen Liang (GDGM 46638).

Comments.

Zhang and Yu (1989) described R. bispora as Chamonixia bispora B.C. Zhang & Y.N. Yu from south China (Dinghushan Nature Reserve, Guangdong Province) based on a single collection (Fig. 2). Lebel et al. (2012) transferred this species to Rossbeevera as it fits within the generic concept of Rossbeevera . This species is characterized by its whitish to grayish brown pileus turning bluish when injured, 2-spored basidia, and is associated with broad-leaved trees in south China.