Crassisporus imbricatus 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 imbricatus B.K. Cui & Xing Ji sp. nov. Figs 3 , 4

Notes.

Crassisporus imbricatus is characterized by imbricate basidiocarps, pale greyish-brown pore surface when dry, round to angular pores (3-5 per mm), and oblong ellipsoid basidiospores (10-14 × 4.5-6.2 μm).

Holotype.

CHINA. Hainan Province, Changjiang County, Bawangling Nature Reserve, on dead angiosperm tree, 9 May 2009, Dai 10788 (BJFC).

Etymology.

Imbricatus (Lat.): referring to the imbricate basidiocarps.

Description.

Fruitbody: Basidiocarps annual, effused-reflexed to pileate, imbricate, soft corky, without odor or taste when fresh, leathery to corky upon drying. Pilei semicircular or elongated, projecting up to 1.5 cm, 3.5 cm wide, and 2.5 mm thick at base. Pileal surface yellowish brown, velutinate, concentrically zonate. Pore surface buff when fresh, becoming pale greyish brown when dry; sterile margin indistinct, pores round to angular, 3-5 per mm; dissepiments slightly thick, entire to slightly lacerate. Context yellowish brown, leathery, up to 2.5 mm thick. Tubes concolorous with context, corky, up to 1.5 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, 2-3.5 μm in diam.; skeletal hyphae dominant, hyaline to pale yellowish brown, thick-walled with a narrow lumen to subsolid, rarely branched, straight, interwoven, occasionally simple-septate, 2.5-5.5 μm in diam.; binding hyphae hyaline to pale yellowish brown, thick-walled with a narrow lumen to subsolid, flexuous, frequently branched, interwoven, 1.2-2.5 μm in diam.

Tubes: Generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 1.5-3 μm in diam.; skeletal hyphae dominant, hyaline to pale yellowish brown, thick-walled, occasionally branched, strongly interwoven, rarely simple-septate, 1.5-3.5 μm in diam.; binding hyphae hyaline to pale yellowish brown, thick-walled with a narrow lumen to subsolid, flexuous, frequently branched, interwoven, 1-2 μm in diam. Cystidia and cystidioles absent. Basidia clavate, bearing four sterigmata and a basal clamp connection, 19-32 × 9-12 μm; basidioles dominant, in shape similar to basidia, but distinctly smaller.

Spores: Basidiospores oblong ellipsoid, hyaline, slightly thick-walled, smooth, IKI-, CB-, 10 –14(– 15) × 4.5 –6.2(– 6.6) μm, L = 12.33 μm, W = 5.34 μm, Q = 2.27-2.36 (n = 60/2).

Type of rot.

White rot.

Additional specimen (paratype) examined.

CHINA. Hainan Province, Changjiang County, Bawangling Nature Reserve, on fallen branch of Pinus latteri , 10 May 2009, Cui 6556 (BJFC).

Figures

Figure 3. Basidiocarps of Crassisporus imbricatus. Scale bar: 2 cm.

Figure 4. Microscopic structures of Crassisporus imbricatus (drawn from the holotype) A basidiospores B basidia and basidioles C hyphae from trama D hyphae from context.