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 Add this item to the list  Ganoderma colossum (Fr.) C.F. Baker
Page number:78 
Remarks (internal):This is a very distinctive species of Ganoderma with the yellow, laccate pilear surface, pale context with slightly dextrinoid skeletal hyphae, large basidiospores, and striking chlamydospores, providing a unique combination of characters. The species is the type of Tomophagus Murrill.
Description type:Non-original description 
Description:Ganoderma colossum (Fr.) C.F. Baker,
V. Cent. Fungi Malay. No. 425, 1918. - Polyporus colossus Fr., Nov. Symb. p. 56. 1851.
Basidiocarps annual, sessile, up to 50 x 25 x 12 cm, very light in weight when dried; pileus firest finely tomentose, quickly developing a thin, laccate cuticle that is easily dented with a fingernail, yellow, becoming yellowish brown or eventually blackening with age; pore surface cream coloured when fresh, darkening to a dull pale brown on age or drying, the pores angular to rounded, 2-4 per mm, with thick, entire dissepiments; tube layer pale vinaceous brown, also soft, up to 2 cm thick, context cream colored to pale buff, soft, fibrous-spongy, azonate, homogeneous, up to 10 cm thick.
Hyphal system dimitic, generative hyphae obscure, thin-walled, with clamps 2.5-4 ?m in diam; skeletal hyphae thick-walled, hyaline, weakly dextrinoid with occasional branching, 2-6 ?m in diam, generative hyphae readily discernible; pilear surface with a dense palisade of clavate thin-walled cells, negative in Melzer's reagent, 32-75 x 7.5-12 ?m.
Chlamydospores scattered through context and rare in the trama, reddish brown in KOH, negative in Melzer's reagent, spherical, thick-walled, with a coarse reticulate surface ornamentation and blunt, cylindric projections up to 4 ?m long and 2 mm wide, main body of spore 18-23 ?m in diam.
Basidia almost spherical with a short narrowed base, apparently 4-sterigmate, 20-30 x 13-17 ?m.
Basidiospores ellipsoid, pale brown in KOH, negative in Melzer's reagent, strongly ornamented, 15-19 x 10.5-12.5 ?m.
Substrata. Hardwoods and of specific hosts recorded on Celtis laevigata.
Distribution. A rare tropical species, known from Florida in USA, Central and South America, and tropics of the old world.
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