Ganoderma aridicola J.H. Xing & B.K. Cui, 2016

Xing, Jia-Hui, Song, Jie, Decock, Cony & Cui, Bao-Kai, 2016, Morphological characters and phylogenetic analysis reveal a new species within the Ganoderma lucidum complex from South Africa, Phytotaxa 266 (2), pp. 115-124 : 119-122

Ganoderma aridicola J.H. Xing & B.K. Cui , sp. nov. ( Figs. 2a , 3 )

MycoBank no.: MB 815623

Basidiocarps perennial, sessile, laccate, pore surface white, pores small (6–8 per mm). Hyphal system trimitic, generative hyphae usually with clamp connections, occasionally with simple septa. Basidiospores double-walled, exospore smooth, endospore with coarse echinulae, IKI–, CB+.

Type:— South Africa, KwaZulu-Natal Province, Durban, on charred wood of Ficus , 01 October 2011, Dai 12588 (Holotype, BJFC! Isotype, IFP!).

Etymology:— aridicola (Lat.) : referring to the species growth in a dry environment.

Fruitbody:—Basidiomata perennial, sessile and broadly attached, corky when fresh, becoming hard corky to woody hard upon drying. Pilei dimidiate, convex, projecting up to 9 cm, 14 cm wide and 4 cm thick at base. Pileal surface laccate, fuscous to black, with white obtuse margin when fresh, becoming reddish brown to black with yellow margin upon drying, with a thin crust and obvious furrows, distinctly concentrically zonate. Pore surface white when fresh, turning brown to dark brown when bruised, clay-buff to dark brown when dry; pores more or less round, 6–8 per mm; dissepiments thin, entire to slightly lacerate. Context corky, fuscous, bearing distinct concentric growth zones, black melanoid band absent, up to 3.4 cm thick at base. Tubes greyish brown, woody hard, distinctly stratified, up to 6 mm long.

Hyphal structure:—Hyphal system trimitic; generative hyphae mostly bearing clamp connections, occasionally with simple septa; skeletal hyphae occasionally with simple septa; all the hyphae IKI–, CB+; tissues darkening but otherwise unchanged in KOH.

Cutis:—Composed of a vertical and closely-packed palisade of cells; cells clavate, yellowish to pale brown, thick-walled, occasionally with blunt outgrowth and protuberance in the apical or lateral parts, moderately amyloid at maturity, 30–55 × 5–8 μm.

Context:—Generative hyphae infrequent, colorless, thin-walled, usually bearing clamp connections, occasionally with simple septa, 2.4–3 μm in diam; skeletal hyphae dominant, pale yellowish brown, thick-walled to subsolid, arboriform, interwoven, occasionally with simple septa, 2.5–5 μm in diam; binding hyphae abundant, pale yellowish brown, thick-walled with a narrow lumen to subsolid, frequently branched, tortuous, interwoven, 1.2–2.5 μm in diam.

Tubes:—Generative hyphae infrequent, colorless, thin-walled, usually bearing clamp connections, unbranched or with a few branches at the distal end, 2.2–2.8 μm in diam; skeletal hyphae dominant, pale brown to distinct brown, thick-walled with a medium or narrow lumen to subsolid, frequently branched, strongly interwoven, 2.3–4 μm in diam; binding hyphae brownish yellow, thick-walled to almost solid, frequently branched, interwoven, 1–2.5 μm in diam. Basidia barrel-shaped, yellowish to pale brown, with a clamp connection and four sterigmata, 15–25 × 8–11 μm; basidioles in shape similar to basidia, 12–20 × 4–8 μm.

Spores:—Basidiospores mostly broadly ellipsoid at maturity, indistinctly truncate, yellowish to pale brown, IKI–, CB+, double-walled, exospore smooth, endospore with coarse echinulate up to 1.7 μm long, (8–)9–11.5(–12) × (5–) 5.3–6.9(–7.2) μm, L = 9.81 μm, W = 5.97 μm, Q = 1.64 (n = 30/1, the turgid vesicular appendix excluded from the measurements).

Type of rot:—Causing a white rot.

Figures

FIGURE 2. Basidiomata of Ganoderma species. a. G. aridicola (holotype); b. G. enigmaticum (Dai 15970). Bars: a=7 cm; b=5 cm.

FIGURE 3. Microscopic structures of Ganoderma aridicola (drawn from the holotype). a. Basidiospores; b. Basidia and basidioles; c. Apical cells from the cuticle; d. Hyphae from context; e. Hyphae from trama. Bars: a–e=10 μm.