Coprosma australis (A.Rich.) Robinson Auckland: House Creek, Little Barrier Island, November 1947, J.M.Dingley, type collection, P.D.D. herbarium, No. 5916; Cow's Creek, Little Barrier Island, November 1947, J.M.Dingley.

Hymenophore resupinate, perennial, brittle, membranous, adnate, effused forming linear areas to 25 x 3 cm. Hymenial surface chocolate with a grey bloom, even, at length deeply irregularly creviced; margin thinning out, chocolate, crenate, closely adnate. Context chocolate, to 500 µ deep, composed of many rows of overlapping setae embedded in scanty upright cemented hyphae, with a delicate zone of compact hyphae lying upon the substratum; hyphal system monomitic; generative hyphae to 5 µ diameter, walls 1 µ thick, dingy brown, or fuscus, sparsely branched, freely and closely septate. Setae arranged in many overlapping rows, projecting to 20 µ, subulate, 24-40 x 5-7 µ, walls coarsely verruculose, ferruginous, lumina harrow. Hymenial layer to 30 µ deep, a scanty palisade of basidia and paraphyses. Basidia subclavate or cylindrical, 20-24 x 5-6 µ, 4-spored; sterigmata arcuate, slender, to 5 µ long. Paraphyses cylindrical, shorter and narrower than the basidia. Spores allantoid, apiculate, 8-9 x 3-3.5 µ, walls hyaline, smooth, 0.1 µ thick.

DISTRIBUTION: New Zealand.

HABITAT: Effused on bark of dead branches associated with a white rot.

Resupinata, perennis, membranacea, fragilis, adnata. Superficies hymenii badia, rimosa; margine badia, crenato, adnato. Contextus badius, ordinibus setarum partim superimpositis, in hyphis erectis inclusis. Hypharum systema monomiticum. Setae subulatae, ad 20 µ eminentes, crasse verruculosae, 24-40 x 5-7 µ. Basidia subclavata vel cylindricalia, 20-24 x 5-6 µ, 4 sporis allantoidibus, 8-9 x 3-3.5 µ.

Specific features are the crowded small setae occupying the thickness of the context, large-diameter thick-walled cemented hyphae, and large allantoid spores. Basidia collapse as soon as spores are shed so are difficult to find save in growing margins. Immature setae of young plants are hyaline, thin-walled, naked and simulate gloeocystidia even to the contents. The surface colour is exactly the shade of weathered chocolate which has developed a greyish bloom. The species most closely resembles H. vallata in surface features, differing in the smaller setae, larger basidia and large spores.

Coprosma australis (A.Rich.) Robinson Auckland: House Creek, Little Barrier Island, November 1947, J.M.Dingley, type collection, P.D.D. herbarium, No. 5916