E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
Also listed in Polypores category. Features include 1) resupinate growth (often partly reflexed to form caps) on wood, more often hardwood, 2) caps when present shelf-like, projecting 1-5cm, often shingled, sometimes fused into formless clusters, soft-cartilaginous (horny when dry), the upper surface whitish to yellowish or pinkish, azonate or somewhat zonate, and tomentose to hairy, 3) a spore-bearing surface that is waxy, soft, gelatinous, translucent, pale orange-yellow to deep orange-red, and merulioid, with folds narrow, radial, branching to less prominent side ridges, sometimes forming nearly rectangular pore-like pits, 1 or 2 per millimeter, 4) spores that are cylindric to allantoid, smooth, inamyloid, and colorless, 5) cystidioles that are cylindric, projecting, and often encrusted, and 6) a monomitic hyphal system, the hyphae with clamp connections. It is common from the southern US to the tree line in Canada (Ginns(12)).

Phlebia tremellosa has been found in BC, WA, OR, ID, AB, MB, NB, NS, ON, PQ, SK, AR, CA, CT, FL, GA, IA, IN, LA, MA, MD, MI, MN, MO, MT, NC, NY, OH, TN, VA, WI, and WV, (Ginns(5)). Besides the United States and Canada, it is widespread in Europe, and also found in Brazil, Uruguay, Morocco, China (including Tibet), India, Japan, Siberia in Russia, and Pakistan, (Ginns(12)). It occurs in Scandinavia (Eriksson) and Switzerland (Breitenbach).

Fruiting body:
resupinate or partly reflexed to form shelf-like caps, often imbricate [shingled], separable when fresh, often confluent, usually 5cm x 3cm but up to 25cm x 10cm, and 0.5cm thick, where caps are present they are soft and cartilaginous (drying horny) and upper surface white to pallid, azonate, and tomentose to hirsute; spore-bearing surface translucent, waxy, when young or fresh pale orange-yellow to deep orange-red, (when dried or in older specimens usually blood red), the folds narrow, 0.05-0.15cm deep, "continuous nearly to the margin, radiating, branching to acute side ridges or dichotomously, occasionally forming elongated and nearly rectangular pits", 1 or 2 per millimeter; margin of resupinate part up to 0.2cm wide, waxy, fimbriate [fringed], translucent, pale yellow to orange-red, occasionally darker; context up to 0.3cm thick, cartilaginous and water-soaked when fresh, (when dry cottony), white to pallid, often striated with waxy hyphal strands, (Ginns(12)), resupinate, orbicular [circular] and confluent, spreading out and reaching a size of several decimeters across, or dimidiate-pileate white caps 1-5cm broad in radial direction, "often elongated lengthwise, now and then imbricate, carnose tremellose when alive and wet", shrunken and with a horny spore-bearing surface when dry; "upperside white, tomentose-strigose, often somewhat zonate", the margin tomentose or hispid [bristly]; spore-bearing surface watery grayish or sallowly ochraceous when young and fresh, turning reddish when mature, (when dried dark ochraceous, sometimes orange or even red), "reticulately plicate (merulioid) with irregular alveoles", radial ridges often dominating over the tangential ridges, in fully developed specimens more or less poroid with fertile ridges between the pores; margin radially fibrillose when resupinate, (Eriksson), "on vertical and laterally extending substrates semipileate to pileate", the caps usually in band-like rows several centimeters to decimeters long, projecting 2-4cm from substrate, sometimes also fused into formless clusters, upper surface white to yellowish with a pink tint, hairy to hispid (from white tomentum), undulating, margin sinuous, white to somewhat translucent; spore-bearing surface merulioid, reticulate-porose, or radially ribbed, "yellow, orange, to salmon-pink, dark orange when old"; consistency soft, elastic, gelatinous; odor and taste insignificant, (Breitenbach), spore deposit white (Buczacki)

Microscopic:
SPORES 3.5-4.5 x 1-1.5(2) microns, cylindric, in side view allantoid to reniform [kidney-shaped], smooth, IKI-, colorless, very pale blue in lactic-blue, thin-walled, some containing 2 droplets; BASIDIA 17-28 x 3-5 microns, of the chiastobasidium type, narrowly clavate; SUBHYMENIUM and hymenium of some specimens with granular deposits throughout; HYPHAE monomitic, context of 2 layers, 1) the abhymenial layer with hyphae 2-5.5 microns wide, randomly oriented, rather loosely woven, colorless, rather thin-walled to thick-walled, with clamp connections, lacking granular deposits, with interspersed waxy strands, 2) abruptly (closer to hymenium) the hyphae become "closely packed, parallel, horizontally oriented", this hyphal layer extending to the hymenium; "at the base of the folds the hyphae are randomly oriented, serpentine, more widely spaced, becoming flexuous and loosely woven in the folds", these hyphae having walls rather thin and with colorless, apparently gelatinous droplets up to 2 microns in diameter, scattered over their exterior, (Ginns(12)), SPORES 4-4.5 x 1-1.5 microns, allantoid, smooth, thin-walled, often with 2 droplets; BASIDIA 4-spored, 18-25 x 4-4.5 microns, narrowly clavate, in a very dense palisade, with a basal clamp connection (new basidia born from the clamp connection); CYSTIDIA not present, but often there are thin-walled hyphae in the hymenium, projecting 20-30 microns, often covered by pieces of excreted resinous matter; HYPHAE monomitic, with clamp connections; CONTEXT of 2 layers: 1) the abhymenial layer white and cottony in section, with distinct hyphae 4-5 microns wide, much branched in all directions, with thickened walls, "forming a net-like tissue, penetrated by strands of parallel hyphae", and 2) layer closer to the hymenium with hyphae 2-3(4) microns wide, thin-walled, irregularly intertwined into a ceraceous context (forming a layer of parallel hyphae instead in the cap trama); SUBHYMENIUM thickening, formed by hyphae 2-3 microns wide, thin-walled, richly branched, in an almost pseudoparenchymatic tissue, (Eriksson), SPORES 3.5-4 x 1(1.5) microns, cylindric, allantoid, smooth, inamyloid, colorless, some with droplets; BASIDIA 4-spored, 20-25 x 3-4 microns, narrowly clavate, with basal clamp connection; CYSTIDIOLES 30-45 x 3-4 microns, cylindric, some encrusted; HYPHAE monomitic, 2-4 microns wide, with clamp connections; HAIRS of upper surface 2-3.5 microns wide, colorless, with clamp connections, (Breitenbach), spore print white (Lincoff(2))