Hymenophore annual, membranous, adnate, effused forming linear areas to 17 x 2 cm; hymenial surface at first olivaceous, becoming fuscus or sepia, delicately pubescent, even, not creviced; margin thinning out, fibrillose, adnate, concolorous. Context olivaceous or fuscus, 100-160 µ thick, intermediate layer of irregularly arranged mainly skeletal hyphae, basal layer narrow, of densely compacted generative hyphae; hyphal system dimitic; skeletal hyphae 4-6 µ diameter, walls 1-2 µ thick in the subhymenial hyphae, lumen almost capillary in the basal hyphae, chestnut-brown to fuscus, septate, sparsely branched and coated with occasional calcium crystals; generative hyphae to 4 µ diameter, walls 0.2 µ thick, hyaline, septate, freely branched, naked, without clamp connexions. Hymenial layer a scanty palisade of basidia and paraphyses interrupted by projecting pseudosetae. Basidia projecting, subclavate, some cucurbitiform, often geniculated, soon collapsed, 35-58 x 8-10 µ, 4-spored; sterigmata erect, to 6 µ long. Paraphyses subclavate, about half the length and diameter of the basidia. Pseudosetae formed from projecting ends of skeletal hyphae, forming the surface of the hymenium and embedding the basidia; 4-6 µ diameter, walls 1-2 µ thick, septate, chestnut-brown, naked or bearing occasional crystals. Spores obovate, with rounded apices and apiculate bases, ovate, oval, or broadly fusiform with bluntly pointed ends, apiculate, 9-13 x 6-7.5 µ, walls smooth, fuscus, 0.75 µ thick.

DISTRIBUTION: New Zealand.

HABITAT: Effused on bark of dead branches.

Hymenophorum annuum, membranaceum, adnatum, effusum; superficies hymenii olivacea deinde fusca vel sepiacca, tenuiter pubescens, aequa, fibrilloso, adnato, concoloro margine. Contextus olivaceus vel fuscus; hypharum systema dimiticum; hyphae skeletales crassis, castaneis vel fuscis parietibus, raris calcii crystalli; hyphae generatoriae hyalinis, tenuibus parietibus, enodulosae. Basidia subclavata vel cucurbitiformis, 35-58 x 8-10 µ. Pseudosetae ex extremis skeletalibus hyphis finctae, 4-6 µ diam., castaneis parietibus nudis vel raris crystallis. Sporae obovatae, ovales vel late fusiformes, apiculatae, 9-13 x 6-7.5 µ, fuscus parietibus, 0.75 µ crassis.

A well defined species which may be recognized by the following features. Colonies are effused, closely adnate, olivaceous or sepia, almost black when old, with concolorous margins. The hyphal system is dimitic, the only species seen with such a feature. Skeletal hyphae are deeply coloured, thick-walled, and apices of the upper hyphae project through the hymenial layer to form the hymenial surface, embedding basidia and paraphyses. Generative hyphae are thin-walled, hyaline, and at the base become compacted to form the basal layer which in old specimens appears almost pseudoparenchymatous. Basidia are irregular in shape and soon collapse. The species links Coniophora with Duportella; for it possesses typical spores of the former, and pseudosetae of the latter.

Leptospermum ericoides A. Rich. Auckland: Kauri Park, Birkdale, January, 1956, S.D. Brook. Leptospermum scoparium Forst. Auckland: Rangitoto Island, June, 1947, J.M. Dingley, type collection, P.D.D. herbarium, No. 5541.