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Page number:144 
Description type:Non-original description 
Description:Phellinus setulosus (C.G. Lloyd) Imazeki Figure 9 Bull. Tokyo Sci. Mus. 6 (1943) 104; Cunningham (1965) 222; Ryvarden and Johansen (1980) 217; Imazeki and Hongo (1989) f. 855.
Fomes setulosus C. G. Lloyd, Myc. Writ. 4 (1915) 243.
Fruit-bodies arising from a massive primordial knob, sessile, broadly attached, applanate, dimidiate, perennial, becoming convex to ungulate, reaching up to 46 cm in radius and 82 cm wide. Pileus in the first season velutinate, dark brown, in succeeding seasons velutinate and dark brown only round the margin, glabrous, smooth, dull grey, fuliginous or blackish from the base outwards, sometimes for a long period fuliginous brown, often gibbous at the base, becoming broadly sulcate, often cracked in dry weather; margin very obtuse, thick, velutinate, rich dark brown, becoming stepped and vertical for up to 6 cm in old specimens. Tubes -2.5 mm long in the first season, 1-1.5 mm near the margin of the pileus, then stratose with layers 1-2 mm thick and more or less continuous or with a very thin intervening layer of flesh, totalling up to c. 45 layers and 96 mm thick, dark brown; pores 70-100 µm wide, dissepiments 30-100 µm thick, velutinate, dark brown. Flesh 35-90 mm thick at the base, 12-25 mm near the margin, rather sappy when young, becoming dense, hard, woody, streaked with whitish mycelial strands from the base, dark ferruginous yellow then dark brown, developing an indistinct fuscous or blackish superficial crust 2-7 mm thick.
Saprophytic on fallen trunks but more commonly parasitic on the trunks and branches of large dipterocarp trees and Koompassia excelsa (Leguminosae) at heights up to 40 m, rarely less than 3 m, above ground. Malay Peninsula, formerly common. S.E. Asia, New Guinea, New Zealand.
Spores 4-5 x 3-4 µm in a few collections 5-6 x 4.5-5.5 µm white in the mass, old spores in the tubes with yellowish to brownish walls, broadly ellipsoid, with smooth thin walls, 1 gutta 1-2.5 µm wide. Basidia 7-10 x 4-5.5 µm ; sterigmata 4, 3 µm long. Cystidioles 16-30 x 3-5 µm subventricose with prolonged apex 1-1.5 µm wide, thin-walled, collapsing. Setae 15-27 x 5-11 µm more or less strongly ventricose, acute, often somewhat curved, very rarely hamate, with very thick dark brown walls, but in a few collections many or most of the setae hamate. Hyphae d5, without clamps; skeletals in the flesh 150-600 µm long, the distal part 50-300 µm long 2.5- 4 µm thick with yellowish brown walls and linear lumen, aseptate, unbranched with obtuse apex or tapered 2-2.5 µm wide, rarely submoniliform, the proximal mediate part 100-300 µm long 1-2 µm wide expanding gradually from the generative hypha, with pale yellowish walls thickening 0.5-1 µm occasionally with an abortive branch near the origin, radial and entwined, reaching full length before wall-thickening; generative hyphae 1-2.5 µm wide with thin colourless or slightly thickened yellowish walls, branched copiously and interwoven, producing the skeletals; dissepiments constructed as the flesh, the tissue becoming at most very slightly agglutinated, some of the skeletal tips projecting into the subhymenium, rarely with transitions to hymenial setae. Hymenium developed gradually from generative hyphae, not thickening. Surface of the pileus with a short close pile of skeletal ends derived from the margin of the pileus, infiltrated from the outset with generative hyphae freely branching, their walls becoming thickened, yellow brown and agglutinating but not strongly, the agglutination extending inwards but the resulting crust never hard and carbonaceous.

Key to varieties of Phellinus setulosus
1. Setae 20-47 x 5-8 µm narrowly conical, straight. Pileus becoming massive, subungulate with convex pore-surface. var. longisetosus
1. Setae 15-27 x 5-1 l µm ventricose, often curved.
2. Pileus 1-2.5 cm in radius, sometimes effuso-reflexed or dorsifixed orbicular. Flesh -2 mm thick. Chiefly on small roots. var. radicicola
2. Much larger, on branches or trunks.
3. Pileus soon ungulae with resupinate extension. Pore-surface convex. Flesh 4-12 mm thick. Setae often hamate. var. ungulatus
3. Pileus applanate, eventually subungulate and very large, without resupinate extension. Flesh 35-90 mm thick. Setae usually not hamate. var. setulosus

Phellinus setulosus var. setulosus
As above.
This is my description of what used to be the most massive and dense xanthochroic fruit-bodies to be found in the lowland Malayan forest. In parts of central Pahang it seemed that every old dipterocarp tree became infected; the fungus probably entered through a broken limb and attacked the heart-wood down to the buttresses. Where the fruit-bodies emerged through the bark, the trunk formed a thick woody nodule and from this purchase the wide shelves projected horizontally. If one allows two seasons a year for fungus growth in Malaya, though it is unknown what periodicity the fruit-bodies may have had in relation to their host, then the largest that I found was about 22 years old. The fungus brackets were so strong and secure and so frequent on some trunks that one could clasp hold of them, climb on to them and mount the trunk for some 15-20 m height. My botanical monkeys leapt on to them and rasped the thick obtuse margin of the bracket as if it were some fungal cheese. These fruit-bodies were the zenith of xanthochroic achievement, thriving on the hearts of those enormous trees, building fruit-bodies with the minutest and most advanced construction, to emit a thin smoke of white spores. How so many millions of microscopic needles can be organised into the building of such precise and durable brackets with their minute pores has never been considered; what minutiae can be studied seem trivial.
There are numerous variations of which I have selected only the more obvious. Concerning var. setulosus, the collection Sing. F.N. 24209 has slightly larger spores 5-6 x 4.5-5 µm and setae -13 µm wide and frequently hamate as in the Sumatran collection which I refer to var. ungulatus. Thus, Cunningham gives the pores 100150 µm wide, the spores 5-6.5 x 4.5-5 µm with thin hyaline walls 0.l µm thick, and setae 16-35 x 8-12 µm mostly hamate. Ryvarden and Johansen give the spores as 57 x 4-6 µm with pale yellow to fulvous, thin to very thick walls (such as I have not seen), and setae 15-40 x 5-16(-20) µm but, in their key, 5-10 µm wide.
The following misnamed collections belong to Ph. setulosus: Sing. F.N. 16439, det. Fomes surinamensis by Lloyd; Bur. Sci. Manila n. 14375, det. Fomes merrillii by Graff; Bur. Sci. Manila n. 36106, det. Fomes robustus by Lloyd.
It is difficult to see how Ph. setulosus differs specifically from the north temperate Ph. igniarius. Perhaps, Ph. setulosus has generally a better developed subcarbonaceous surface to the pileus, slightly smaller pores and spores, somewhat longer setae and slightly narrower skeletals, but these hardly amount to specific difference. If mycology had begun in the tropics, Ph. igniarius would have been a variety of Ph. setulosus.
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