Crassisporus macroporus B.K. Cui & Xing Ji

Ji, Xing, Wu, Dong-Mei, Liu, Shun, Si, Jing & Cui, Bao-Kai, 2019, Crassisporus gen. nov. (Polyporaceae, Basidiomycota) evidenced by morphological characters and phylogenetic analyses with descriptions of four new species, MycoKeys 57, pp. 61-84 : 61

Crassisporus macroporus B.K. Cui & Xing Ji sp. nov. Figs 7 , 8

Notes.

Crassisporus macroporus is characterized by cream-buff to cinnamon-buff colored pore surface with distinct sterile margin when fresh, large pores (2-3 per mm) with thin dissepiments, a trimitic hyphal system with cyanophilous skeletal hyphae, the presence of fusoid cystidioles, and oblong ellipsoid basidiospores (9.5-13.2 × 4-6.2 μm).

Holotype.

CHINA. Guangxi Autonomous Region, Huanjiang County, Mulun Nature Reserve, on fallen angiosperm branch, 10 July 2017, Cui 14468 (BJFC).

Etymology.

Macroporus (Lat.): referring to the large pores.

Description.

Fruitbody: Basidiocarps annual, effused-reflexed to pileate, corky to leathery, without odor or taste when fresh, soft leathery upon drying. Pilei flabelliform, semicircular or elongated, projecting up to 1.5 cm, 4 cm wide and 5 mm thick at base; resupinate part up to 7 cm long, 4 cm wide, and 5 mm thick at center. Pileal surface buff to yellowish brown when fresh, becoming yellowish brown upon drying, finely velutinate, concentrically sulcate. Pore surface cream, buff to cinnamon-buff when fresh, becoming buff, pale yellowish brown to yellowish brown when dry; sterile margin distinct, buff to pale yellowish brown, up to 2 mm wide; pores round to angular, 2-3 per mm; dissepiments thin, entire to lacerate. Context yellowish brown to pale yellowish brown, leathery, up to 1.5 mm thick. Tubes pale yellowish brown, corky, up to 2 mm long.

Hyphal structure: Hyphal system trimitic; generative hyphae bearing clamp connections; skeletal and binding hyphae IKI-, CB+; tissues turning to black in KOH.

Context: Generative hyphae infrequent, hyaline, thin-walled, unbranched, 1.5-3.5 μm in diam.; skeletal hyphae dominant, pale yellowish brown, thick-walled with a narrow lumen to subsolid, unbranched, more or less straight, interwoven, occasionally simple-septate, 2-5.5 μm in diam.; binding hyphae hyaline to pale yellowish brown, thick-walled with a narrow lumen to subsolid, flexuous, frequently branched, interwoven, 1-3 μm in diam.

Tubes: Generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 1-2 μm in diam.; skeletal hyphae dominant, hyaline to pale yellowish brown, thick-walled with a narrow lumen to subsolid, occasionally branched, more or less straight, strongly interwoven, 1.5-3 μm in diam.; binding hyphae hyaline to pale yellowish brown, thick-walled with a narrow lumen to subsolid, flexuous, frequently branched, interwoven, 0.8-2 μm in diam. Cystidia absent, cystidioles fusoid, hyaline, thin-walled, 13-20 × 4.5-6 μm. Basidia clavate, bearing four sterigmata and a basal clamp connection, 17-28 × 7-8 μm; basidioles dominant, in shape similar to basidia, but smaller.

Spores: Basidiospores oblong ellipsoid, hyaline, smooth, slightly thick-walled, IKI-, CB-, 9.5 –13.2(– 14) × 4 –6.2(– 6.5) μm, L = 11.24 μm, W = 4.96 μm, Q = 2.26-2.31 (n = 60/2).

Type of rot.

White rot.

Additional specimen (paratype) examined.

CHINA. Guangxi Autonomous Region, Huanjiang County, Mulun Nature Reserve, on dead angiosperm tree, 10 July 2017, Cui 14465 (BJFC).

Figures

Figure 7. Basidiocarps of Crassisporus macroporus. Scale bars: 2 cm.

Figure 8. Microscopic structures of Crassisporus macroporus (drawn from the holotype) A basidiospores B basidia and basidioles C cystidioles D hyphae from trama e hyphae from context.