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 Add this item to the list  Phellinus rimosus (Berk.) Pilát
Page number:135 
Description type:Non-original description 
Description:Phellinus rimosus (Berk.) Pilát
Ryvarden and Johansen (1980) 207.
cf. Ph. kawakamii Larsen, Lombard et Hodges, Mycologia 77 (1985) 346. Fruit-body unipileate, perennial, sessile, applanate, horizontal, -38 cm in radius, -54 cm wide, or usually becoming more or less ungulate -12.5 cm in radius, -22 cm wide and 18 cm high, sometimes effuso-reflexed. Pileus subvelutinate to matt, narrowly to rather distantly sulcate, often somewhat tuberculate, auburn to dark ferruginous brown near the margin, soon becoming duller brown and finally scabrous glabrescent fuscous blackish and often rimose with radial and tangential splits; margin velutinate, obtuse, bright golden fulvous. Tubes 2-11 mm long in the first season, 0.5-2 mm at 5 mm from the margin of the pileus, developing indistinct layers 1-3 mm thick, rarely separated by a layer of flesh 0.3-0.5 mm thick, reaching up to 13 cm thick with c. 40 layers, concolorous with the flesh; pores 100-150 (-180) µm wide, dissepiments 40-100 µm thick, entire, dark brown with a golden sheen when fresh. Flesh 4-50 mm thick at the base of the pileus, 2-10 mm at 5 mm from the margin, fibrous woody, sappy, drying hard, varying bright fulvous ochraceous to fulvous cinnamon, finally dull ferruginous brown, upper surface slowly agglutinated into a carbonaceous or subcarbonaceous black crust 0.5-2.5 mm thick; old perennial fruit-bodies developing thin black crustaceous anastomosing strands or plates in the flesh, and with pale yellowish white strands of incursive mycelium.
On stumps and fallen trunks or parasitic up to 10 m high on trunks of large trees (Carapa, Casuarina, Dialium, Lumnitzera, Podocarpus and others). Malay Peninsula, common. Pantropical.
Spores 4-5.5 x 3.5-4.7 µm, rarely 5-6.5 x 4.5-5.5 µm, ferruginous ochraceous in the mass, broadly ellipsoid to ellipsoid subreniform, with smooth slightly thickened walls and a minute pore at the base, 1 gutta 1-2.5 µm wide or sometimes merely guttulate. Basidia 9-13 x 5-9 µm ; sterigmata 4, 2-2.5 µm long. Cystidioles -25 x 48 µm with a filiform apex -20 x 1-2 µm, thin-walled, only near the pores, evanescent. Setae none. Hyphae d4, without clamps; skeletals in the flesh 3-5 µm wide, 450-800 µm long, septate at intervals of 100-400 µm rarely with secondary septa, walls thickening strongly to obliterate the lumen, unbranched; generative hyphae 23.5 µm wide; dissepiments with similar and slightly narrower skeletals, not agglutinated. Surface of pileus with a short compact pile of skeletal ends becoming agglutinated with few incursive generative hyphae, the agglutination beginning at the surface or at depths up to 1 mm below the surface, the whole upper layer eventually agglutinated but not strongly (thus rimose on drying).
This is a large unwieldly fungus that is by no means easy to interpret microscopically. I instance a few of the problems. At first, I took the wall of the spore to be 0.5 µm thick and then decided that it was an optical effect because the wall of crushed spores was c. 0.1-0.2 µm thick; yet, a pore, not an apiculus, marked the sterigmatic attachment. The fruit-bodies in any one gathering tend either to be applanate, even slightly ascending, or more or less ungulate, especially when parasitic; both states are perennial. In some collections the spores are 4-4.5 x 3.5-4 µm and 4.5-5 x 44.5 µm in others, and yet others are intermediate. Similarly, the skeletals of the flesh vary 3-4(-5) µm wide to 4-5 µm wide in other collections, again with intermediates; however, individual skeletals may vary in this way in different parts of their length.
On the east coast of Johore, at Jason Bay, trees of Casuarina equisetifolia develop as a primary forest on the sand-dunes and some persist as giant, moribund, trees in the lowland dipterocarp forest which replaces them. Ph. rimosus attacked many of these old trees, the fruit-bodies issuing from the rotting heart-wood and at the base of dead and dying branches; it certainly accelerated, if it did not inflict, the death of these trees which are unable to regenerate in closed forest. One collection from these trees (June 1934) had large subglobose spores 6-7 µm wide with the yellow brown walls truly thickened -0.5 µm The skeletals of the flesh were 3.5-5 µm wide and 450-850 µm long. A collection from Podocarpus neriifolius, beside the Sedili River which flows into Jason Bay, was typical except for the scarcely rimose surface of the pileus, the crust being scarcely developed; it had pores 120-180 µm wide and skeletals in the flesh 3-4.5 µm wide. Other collections on the same day (25 Nov. 1934), growing on living trunks of Lumnitzera littorea and L. racemosa (Combretaceae), with fruit-bodies on the trunks of the former up to 10 m above the ground, agreed macroscopically with Ph. rimosus but the skeletals of the flesh were 4-5.5(-6) µm wide and were more or less unlimited with fairly wide lumen as in Ph. fastuosus; they had the dark flesh and rimose pileus of Ph. rimosus and pores 120180 µm wide. Large subungulate fruit-bodies, up to 19.5 cm in radius, 41 cm wide and 4 cm thick, grew parasitically from various unidentified kinds of tree in the swamp forests about the Sedili River had thin flesh 3-6 mm thick at the base of the pileus, skeletals merely 2.5-4(-5) µm wide, and spores 4-4.5 x 3-3.5 µm they tended towards Ph. caryophylli. But, of all species, the closest ally of Ph. rimosus seems to be Ph. fastuosus, such that they could be regarded as extremes of one species. Ph. rimosus is distinguished by the narrower and limited skeletals which are not encrusted, the less strongly agglutinated crust with few intrusive generative hyphae so that it is scabrid and rimose, the darker brown flesh, the somewhat wider pores, the slight tomentum on the pileus and its ungulate tendency. Even so, I had several collections which seemed to be intermediate. The Hawaiian Ph. kawakamii differs in the imbricate pilei, bright ferruginous colour and presence of chlamydospores.
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