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Page number:147 
Description type:Non-original description 
Description:Heterobasidion hemitephrum (Berkeley) comb. nov. Plate Id Polyporus hemitephrus Berk., Fl. N.Z. 2 : 179, 1855. Polyporus hemitephrius Berk., Hdbk. N.Z. Flora, p. 608, 1864. „ Polyporus hypopolius Kalch. ex Cke., Grevillea 10 : 99, 1882. Fomes hemitephrus (Berk.) Cke., Grevillea 14 : 21, 1885. Fomitopsis hemitephra (Berk.) G. H. Cunn., N.Z. D.S.I.R. Pl. Dis. Div. Bull. 76 : 2, 1948.
Hymenophore perennial, solitary, hard and woody, attached by a broad lateral base. Pilei applanate or ungulate, 3-20 cm wide, 3-12 cm radius, 1-10 cm thick; pileus surface at first ochre or fawn, becoming bay banded with greyish zones, tobacco brown or fuscous and concolorous, umber in old specimens or sometimes black, strongly concentrically sulcate, often concentrically banded with different shades of brown, finely tomentose becoming glabrous; cortex to 1 mm thick, chestnut with an orange zone beneath, ligneous, brittle, composed of densely intertwined cemented hyphae with chestnut walls; margin bluntly rounded, or thickened and formed from numerous equal growth layers when concentrically sulcate; hymenial surface at first white or straw, drying isabelline, even, slightly concave or as often convex, with a narrow rounded sterile border 2-3 mm wide. Pores in many often obscure strata (2-18), sometimes with zones of context hyphae between, 3-10 mm deep in each layer, wood colour, round or slightly angular, 6-7 per mm, 50-150 µm diameter; dissepiments 50-200p thick, commonly 75-100 ,u,, equal, apices even. Context cream or isabelline, to 15 mm thick, often zoned, of densely intertwined hyphae; skeletal hyphae to 4 µm thick, lumena 1.5-2 µm diameter, aseptate, scantily branched and undulate near ends, staining; generative hyphae to 3 µm diameter, walls thin, not staining, sparsely branched, septate in the subhymenium. Hymenial layer to 20p deep, a loose palisade of basidia and paraphyses, soon collapsing. Basidia clavate, 8-10 x 4-5 µm, bearing 4 spores; sterigmata erect, to 4 µm long. Paraphyses subclavate, 6-8 x 3.5-4 µm. Spores elliptic-oblong, 4-6 x 2-2.5 /j,, walls smooth, hyaline, 0.1 µm thick.
TYPE LOCALITY: Coromandel Peninsula, Auckland. DISTRIBUTION: New Zealand, Australia, Samoa.
HABITAT: Bark or decorticated wood of standing or fallen trunks, associated with a white heart rot.
IN KEW HERBARIUM: Collections are the type ex "N.Z., Coromandel, Colenso", "N.Z., Colenso, b262, b375", "N.Z., Hokianga, Berggren", "N.Z., Napier, Colenso", "Q., Brisbane, Cheesman", "N.S.W., Moruya, Cheesman", "Vic., Miss Campbell", "Vic., D.F.P. 2806" filed under Fomes hemitephrus; "Q., Trinity Bay, W. A. Sayer" under the cover of Fomes exotephrus; "Q., Barron River" under Fomes fâsciatus; "N.S.W., Richmond River, Mrs Hodgkinson" a resupinate specimen under Poria medulla panis; "N.S.W., Sydney, W. W. Froggatt" communicated by C. G. Lloyd as Fomes martius; and "Samoa, Lloyd" filed under Fomes ferreus.
One of the most common species in New Zealand, which may be recognised by the usually dark colour of the strongly sulcate pileus surface, conspicuous cortex with an orange zone between it and the context, small pores, usually numerous pore layers, and small elliptical spores. Commonly
applanate, pilei may be ungulate or resupinate; each successive pore layer may grow to the edge of the preceding when the margin becomes thick and banded with many concentric sulcate zones, or successive layers may recede, forming islands or irregular obconic fructifications. Pores may be in definite strata each defined by a differently coloured line, or by layers of context hyphae; or in other collections pores may be obscurely stratose, or even appear to be continuous. The hymenial layer soon collapses and appears on walls of dissepiments of mature plants as an amorphous mucilaginous film.
Lloyd (1915a, p. 215) recorded the species from New Zealand as Fomes hormodermus and from Australia as F. martius. From these Heterobasidion hemitephrum may be separated by the different spores, smaller pores and presence of an orange zone in the context beneath the cortex. This last feature may be absent from young plants, but may be seen where fructifications are in contact with the substratum, and occasionally the surface of the wood is stained orange.
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