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Literature:
 
Page number:60 
Description type:Non-original description 
Description:Polyporus isidioides Berk. in Hookers Lond. J. Bot. 2 : 515 (1843). Trametes isidioides (Berk.) Fr. in K. Ved. Ak. Handl.: 130 (1848). Plate 6D
"Pileo suberoso-lignoso uniformi convexo duro gilvo-ferrugineo margine subtiliter velutino ruguloso, postice setoso-scaberrimo; intus rhabarbarino; ' hymenio piano cinnamomeo; poris minutissimis punctiformibus. Zeyher, n. 115.
Upon trees, in forests near Uitenhage. March.
Pileus 3 inches broad, 2 long, reniform, convex above, plane below, stemless, of a rich ferruginous reddish grey, hard and woody, very obscurely zoned, minutely rugulose, and velvety toward the margin, with occasionally smooth, shining, darker zones behind, remarkably scabrous with elongated bristly nodules; substance hard, rhubarb-coloured. Hymenium cinnamon." "Pileus corky-woody, uniformly convex, hard, gilvous-ferrugineous, with margin subtly velvety rugulose, setose-scabrous behind; internally yellowishbrown; hymenium flat, cinnamon-coloured; pores very small, punctiform. Zeyer, n. 115".
Unfortunately the type cannot be traced at Kew; there are two sporophores named by Berkeley, 1. without data, 2. from Cape of Good Hope, Drbge, 9437.d. It is this latter which I designate at the Neotype of P. isidioides. A description follows:
Sporophore 9,3 cm long, 4,5 cm from point of attachment to margin, dimidiate, with a broad base, and an acute, somewhat lobed and sterile margin. The surface is very rough and densely granular behind, becoming less so toward the margin and appearing almost smooth, although still minutely granular under a lens. Pores very minute, invisible to the eye, 8-10 per mm, rounded, yellowish brown with a greyish or purple tint; tubes indistinctly stratose in older portions of the fruitbody, up to 2 mm deep, but in total, including all the strata up to 1 cm. Flesh thin, yellowish brown, blackening with 10% KOH; cuticle at least in places, black, thin. Hyphal structure dimitic. Skeletal hyphae 3,5-4,5(-5,0) µmwide, deep brown, with thickened walls but retaining a wide lumen at least 0,3 of the width of the hypha, and this lumen is indistinctly septate. Toward the obtuse apex the skeletal hyphae become thinwalled and the septa, which are secondary, more obvious. Generative hyphae, 2,5-3,0 µm wide, pale brown or hyaline with only slightly, if at all thickened, walls, branched, septate, devoid of clamp-connexions. In younger portions of the flesh near the margin the skeletals are mostly about 5 µm diam., with fairly wide lumen, often occupying half the width of the hypha. The flesh of the dissepiments is composed of similar hyphae, but the skeletals are 2,5-3,0 µm wide and have a narrower lumen. Setae abundant, 16,0-29,0 x 6,2-8,0 µm, fusiform, subulate, with thick, very dark brown walls. Hymenium present, 6 µm wide, composed of indistinct, agglutinated basidia. Spores not seen, but almost certainly hyaline.
This has to be relegated to synonymy under Phellinus gilvus (Schw.) Pat.
 
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