Sidera borealis Z.B. Liu & Yuan Yuan, 2023

Liu, Zhan-Bo, Zhou, Hong-Min, Liu, Hong-Gao & Yuan, Yuan, 2023, Taxonomy and phylogeny of Sidera (Hymenochaetales, Rickenella clade) from China and North America revealing two new species, MycoKeys 96, pp. 173-191 : 173

Sidera borealis Z.B. Liu & Yuan Yuan sp. nov.

Figs 4 , 5

Diagnosis.

Sidera borealis is characterized by annual, resupinate basidiomata with cream to pinkish buff dry pore surface, angular pores (6-7 per mm), a dimitic hyphal system, and allantoid basidiospores measuring 3.9-4.1 × 1-1.1 μm.

Holotype.

China, Shannxi Province, Zhashui County, Niubeiliang Forest Park, on fallen angiosperm trunk, 16.IX.2013, Cui 11216 (BJFC 015331).

Etymology.

Borealis (Lat.): referring to the species occurring in boreal areas of China.

Basidiomata.

Annual, resupinate, soft corky and without odor or taste when fresh, corky when dry, up to 5 cm long, 2 cm wide, and less than 1 mm thick at center; pore surface white to cream or pale buff when fresh, becoming cream to pinkish buff when dry; sterile margin indistinct, white, cottony, thinning out; pores angular, 6-7 per mm; dissepiments thin, entire; subiculum very thin to almost absent; tubes concolorous with poroid surface, less than 1 mm long.

Hyphal structure.

Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae dominant; all hyphae IKI-, CB-; tissue unchanged in KOH.

Subiculum.

Generative hyphae hyaline infrequent, thin-walled, occasionally branched, 1-2 μm in diam; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, occasionally branched, flexuous, interwoven, 1-3 μm diam.

Tubes.

Generative hyphae hyaline occasionally present, thin-walled, rarely branched, 1-2 μm in diam, dominating at dissepiment edges; skeletal hyphae thick-walled with a narrow to wide lumen, occasionally branched, flexuous, interwoven, 1-3 μm diam; rosette-like crystals present, 3-6 μm in diam; cystidia absent; cystidioles present, fusoid, hyaline, thin-walled, basally swollen, with a sharp or often hyphoid neck, 17-19 × 2.5-3 μm; basidia barrel-shaped, hyaline, bearing four sterigmata and with a basal clamp connection, 7-8 × 3.5-4 μm; basidioles in shape similar to basidia, but slightly shorter.

Spores.

Basidiospores allantoid, hyaline, thin-walled, smooth, occasionally with one or two guttules, IKI-, CB-, (3.5-)3.9-4.1(-4.2) × (0.8-)1-1.1(-1.4) μm, L = 4.01 μm, W = 1.06 μm, Q = 3.78 (n = 60/1).

Additional specimens examined.

China, Gansu Province, Zhuoni County, Yaohe Nature Reserve , on rotten wood of Abies , 19.VIII.2022, Dai 24187 (BJFC 039430); on rotten wood of Picea , 18.VIII.2022, Dai 24120 (BJFC 039364) ; Jilin Province, Antu County, Dongfanghong Forest Farm, on rotten wood of Pinus , 25.VII.2022, Dai 23803 (BJFC 039047) ; Qinghai Province, Nangqian County, Baizha Forest Farm, on rotten wood of Picea , 7.VIII.2022, Dai 23960 (BJFC 039204); Dai 23962 (BJFC 039206) ; Yunnan Province, Deqin County, Baimaxueshan Nature Reserve , on rotten wood of Picea , 5.IX.2021, Dai 22822 (BJFC 037395) .

Figures

Figure 4. Basidiomata of Sidera borealis (Paratypes) A Dai 24120 B Dai 22822 C Dai 23960 D Dai 24187. Photo by: Yu-Cheng Dai.

Figure 5. Microscopic structures of Sidera borealis (Holotype, Cui 11216) a basidiospores b basidia and basidioles c cystidioles d hyphae from subiculum e hyphae from trama f hyphae at dissepiment edge. Drawings by: Hong-Min Zhou.