This is a species of Antrodiella Ryv. & Johans. because of the dense basidiocarp, dimitic hyphal system, small spores, and minute pores with a resinous appearance. It is separated from other species in the genus by the black lines between successive strata of the tubes and by the thickness of the basidiocarp (to 2.5 cm thick). In some collections, scattered, dark-brown, granular deposits are present on walls of the skeletal hyphae. The spores are slightly larger and the pores smaller than those of A. semisupina (Berk. & Curt.) Ryv., the type species.

Holotype: PDD 3868 - New Zealand, Rangitikei, Ruahine Ranges, Ngatimoti (?), 27 Jan. 1933, J.G. Gibbs, on Metrosideros robusta A. Cunn.

Hymenophore to 8 x 4 cm., 6-10 min. thick, firm, horny, hard, wood-coloured when dry; margin tapering, irregular, to 2 mm wide, floccose, not lifting, cream coloured; surface even, compact, dissepiments not toothed. Pores wood-coloured in section, stratose, round or slightly angular, to 4 mm. deep, each layer separated by a black line 0.5 mm. thick, 50-150 µ diameter, or 7-9 to mm.; dissepiments 30-100 µ thick, apex tapering, appearing as a firm even layer, of cemented parallel hyphae, not velutinate. Context to 0.8 mm. thick, thinner when old, white or isabelline, hyphae parallel or slightly woven, passing unchanged into the dissepiments; skeletal hypha 3-4 µ thick, thick-walled, lumen often almost obliterated, hyaline, aseptate, sparsely branched near ends, irregular; generative hyphae to 2 µ thick, branched, septate, thin-walled, clamp connections present. Basidial type clavate, basidia clavate, to 10 x 4 µ, soon collapsing. Spores ovate, elliptical, or pip-shaped, 3.5-4 x 2-2.5 µ, smooth, hyaline.

New Zealand.

Metrosideros robusta A.Cunn., on decorticated fallen trunk lying on the forest floor.

Characters of the species are the firm, horny, wood-coloured hymenophore (when dry), stratose minute pores with layers differentiated by a black line, thin dissepiments, aseptate sparsely branched skeletal hyphae with almost obliterated lumen, clavate basidia and small ovate or elliptical spores. The specific name is taken from the Maori name applied to the host.

Wellington. Ngatamoti, Ruahine Ranges, 2,800 feet, Jan. 1933, J.G.Gibbs, type collection.

UNKNOWN HOSTS. Tasmania, Cascades, Hobart, type collection (herb. Cleland). Victoria, Sherbrooke Forest, Dandenong Ranges.

Hymenophore biennial or perennial, loosely attached, effused forming irregular linear areas 3-7 x 2-5 cm, 2-5 mm thick, obscurely stratose. Hymenial surface even, dull white drying dingy buff, not creviced; margin abrupt, 1-3 mm wide, white, fibrillose, adherent, base almost black. Pores in 2-3 vague layers, round or subangular, 4-5 per mm, 50-150 µm diameter, 1-2 mm deep in each layer, stuffed when old; dissepiments 50-100 µm,thick, equal, at first finely velutinate at apices, becoming even. Context dull white, 0.5-1 mm thick, of densely intertwined hyphae embedding numerous crystals; skeletal hyphae 2.5-3 µm diameter, lumena almost obliterated, sparsely branched, irregularly waved, aseptate ; generative hyphae 2-2.5 µm diameter, walls 0.25 µm thick, branched, septate, with abundant clamp connections. Hymenial layer to 16 µm deep, a close palisade of basidia and paraphyses. Basidia subclavate, 8-12 x 3.5-4 µm, bearing 4 spores; sterigmata erect, to 4 µm long. Paraphyses subclavate, 6-10 x 3-3.5 µm. Spores cylindrical or allantoid, 3-3.5 x 1-1.5 µm, walls smooth, hyaline, 0.1 µm thick.

DISTRIBUTION: Australia, Tasmania.

HABITAT: Decorticated fallen trunks, associated with a white rot.

Although the type is sterile, the collection from Victoria bears spores as described and matches the type in other features. Identified by the vaguely stratose pores, soft white context, irregular skeletal hyphae with almost capillary lumena, and small allantoid spores. Pores of old layers are stuffed, and sometimes plants are rigid with hyphae cemented with mucilage as in those of P. rata. In the hymenium of the type collection are numbers of fusiform paraphysate hyphae with delicate aeuminate apices; but these are wanting in the Victorian specimen. Bases of plants, which are loosely attached, are fuscous or almost black, a few of the basal hyphae possessing discoloured walls.

TYPE LOCALITY: Cascades, Hobart, Tasmania.