Polyporales » Polyporaceae » Pyrofomes

Pyrofomes demidoffii

Pyrofomes demidoffii (Lév.) Kotl. & Pouzar 1964, in Cui, et al., Fungal Diversity 97, 137392 (2019)

Diagnosis: Basidiocarps perennial, pileate. Pilei solitary or a few imbricate, corky, without odor or taste when fresh, becoming woody hard upon drying. Pilei ungulate, projecting up to 12 cm, 15 cm wide and 14 cm thick at base. Pileal surface yellowish brown to ash gray, distinctly becoming paler from base towards margin, tomentose or matted when juvenile, becoming grayish black and rimose with age, sometimes covered by mosses, indistinctly concentrically zonate or sulcate; margin blunt, cream to pinkish buff when actively growing. Pore surface ochraceous buff to buff when fresh, cinnamon brown to fulvous when dry; pores round, 34 per mm; dissepiments fairly thick, matted, entire to slightly lacerate. Context cinnamon to brick-red when fresh, yellowish brown to rusty tawny and hard corky when dry, concentrically zonate, up to 4 cm thick; usually with a thick cuticle present at the upper surface, dark gray. Tubes concolorous with pore surface, paler than context, corky to brittle, azonate, indistinctly stratified, up to 5 cm long. Hyphal system dimitic; generative hyphae bearing clamp connections; skeletal hyphae weakly dextrinoid (especially in mass) to non-dextrinoid, weakly CB+; tissues darkening or pinkish darkening in KOH. Generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 23 µm in diam; skeletal hyphae dominant, brownish, thick-walled, mostly with a wide lumen, occasionally branched, straight, regularly arranged, 3.55 µm in diam. Generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 1.82.8 µm in diam; skeletal hyphae dominant, brownish, thick-walled with a wide to narrow lumen, occasionally branched, straight, subparallel along the tubes, 34 µm in diam. Hymenium usually collapsed. Cystidia absent; fusoid cystidioles occasionally present, 2026 × 35 µm. Basidia usually infrequent, pear-shaped, with four sterigmata and a basal clamp connection, 2024 ×89 µm; basidioles in shape similar to basidia, but slightly smaller. Rhomboid crystals frequently present in hymenium. Basidiospores ellipsoid, mostly truncate, pale brownish, thick-walled, smooth, slightly dextrinoid (especially in mass) and weakly CB+, (6–)6.57.8(– 8.4) × (5–)5.16.2(–6.9) µm, L = 7.04 µm, W = 5.6 µm, Q = 1.26 (n = 30/1).

Index Fungorum NumberIF338105

Notes: Pyrofomes demidoffii is readily distinguished from species of Perenniporia by the bright rusty red color of context and its restriction to Juniperus. Previously, P. demidoffii has been recorded on junipers in Africa, North America, Central Europe and China (Ryvarden & Johansen 1980; Gilbertson & Ryvarden 1987; Ryvarden & Gilbertson 1994; Dai & He 2009). It grows exclusively on Juniperus spp., and always causes a white trunk rot of living junipers. It is a serious parasite in old stands of Juniperus sp., and is a major decay fungus in junipers in western North America (Scharpf 1993).