Ganoderma nasalanense

Ganoderma nasalanense Hapuar., Pheng., & K.D. Hyde

Index Fungorum number: 634621; Facesoffungi number: FoF05658

Basidiome annual, laccate, sessile, usually with a distinctly contracted base, corky, becoming hard corky to woody hard when dry. Pileus 4.5–10 × 2–5 cm, several layers thick, applanate, subreniform; upper surface dark brown (8F8) to grey (8B1), distinctly concentrically sulcate, irregularly ruptured crust overlying the context. Margin 3 mm thick, soft, concolorous with the pileus; lower surface dark brown (7F8). Hymenophore up to 15 mm long, indistinctly stratose; pores initially greyish brown (6E3), bruising dark brown (8F6). Pores circular or sub-circular, 3–5 per mm. Context 2 cm thick, duplex; upper layer brown (6E4) to dark brown (7F8), fibrous, composed of coarse loose fibrils; lower layer dark brown (7F8), woody. Basidiospores (n = 21) (6.6)8.6–9.5–10.4(10.7) × (4.4)4.9–5.5–6.1(6.7) μm (with myxosporium, Qm = 1.7, Q = 1.2–2.9). (5.0)6.9–7.8–8.8(10.0) × (3.4)4.0–4.4–4.9(5.2) μm (without myxosporium, Qm = 1.7, Q = 1.1–2.6), ellongate, with a light brown (6D6) eusporium bearing fine, short and distinct echinulae, overlaid by a hyaline myxosporium. Pileipellis a hymeniderm, brownish-orange (5C5), clavate like cells. Context dimitic; generative hyphae not observed; binding hyphae (n = 25), (1.8–3.2–4.8) μm in width, brownish orange (6C8), branched, with clamp-connections, skeletal hyphae (n = 25) (4.2–6.1–7.3) μm in width, brownish-orange (6C8), thick-walled, sometimes branched (Fig. 1).

Etymology: Refers to the collecting site‘Nasala’, Laos

Holotype: GACP17060211

Habitat:  On a decaying hardwood tree trunk, accompanied in humus-rich soil with over heavily rotted litter on the ground.

Specimens examined: LAOS, Huaphanh Province, Samneua District, Nasala Village, 20°22′N–103°98′E, elev. 1346 m, 25 August 2016, P Phengsintham (GACP17060211, GACP17060212).

Notes: Ganoderma nasalanense is a new member of Ganoderma and it is distinguished by dark brown to grey pileus, duplex context, trimitic hyphal system and relatively large, broadly ellipsoid to ellipsoid, light brown spores (12.1–13.8 × 9.2–10.5) μm. It clusters with G. orbiforme (Fr.) Ryvarden and morphologically similar in having rigid basidiocarp, purplish black laccate crust, purplish-brown pore surface, brown tube layer, mostly truncate basidiospores with fine and short echinulae (10–12 × 6.5–7.5) μm, and cuticle composed of strongly amyloid, clavate cells usually with several irregular lobes or protuberances (30–80 × 3–10.5) μm. The species is currently only known from the type locality, Nasala village, Huaphanh Province, Laos. (from Hapuarachchi et al. 2019)