On dead Dysoxylon spectabile, Auckland, Titirangi, Atkinson Park, ll.XII.1966, R. F. R. McNabb (HOLOTYPE, PDD 25608); 6.I.l967, R. F. R. McN., 25609.

Fructifications soft-waxy to fleshy, resupinate, thin, effused, indeterminate, forming irregular areas to 10 cm in longest dimension, surface pruinose, white to greyish-white when fresh, drying to a white or colourless, inconspicuous film; margins concolorous, adnate. In section 25-75 µm thick, consisting of basal layer and hymenium. Basal layer thin, indistinct, composed of thin-walled, hyaline, agglutinated hyphae lying parallel with substratum, clamp connections present. Hymenium composed of paraphysoids and basidia, dikaryophyses absent; paraphysoids abundant, arising from basal hyphae or base of fertile hyphae, variable in shape, cylindrical to subclavate or clavate, often irregular or strangulated, hyaline, thin-walled, contents occasionally faintly yellow but not granular, 11-22 x 4.5-7,0 µm probasidia initially globose, later obovate to suburniform, proliferating through or near basal clamp connections, 5.8-8 x 4.5-5.5 µm  becoming  longitudinally  cruciate-septate;  sterigmata subulate, to 8 µm long. Basidiospores globose to subglobose, occasionally napiform, hyaline, minutely and symmetrically apiculate, smooth, 3-4 µm diam. Germination not observed.

Dead angiosperm wood.

Fructificationes molliter ceraceae ad carnatas, resupinatae, tenues, pruinosae, albae ad albidas; ordo basalis factus ex hyphis indistinctis, nodosis. Dikaryophyses absunt; paraphysoidea cylindrica ad clavata. saepe irregularia, 11-22 x 4.5-7 µm; probasidia ovata ad suburniformia, 5.8-8 x 4.5-5.5 µm, per longitudinem cruciata-septata; sterigmata subulata, ad 8 µm longa. Basidiosporae globosae ad subglobosas, 3-4 µm diam. Habitat in mortuo Dysoxylo spectabili.

In a number of features, Sebacina minutispora resembles S. grandinioides (Bourd. & Galz.) Rogers. It differs in the smooth hymenium, absence of gloeocystidia with yellow or brownish, granular contents, and absence of an involucre of collapsed basidia surrounding the fertile hyphae. The gloeocystidia-like paraphysoids are abundant but at no stage possess granular contents.
Sebacina minutispora is characterised by the numerous paraphysoids, small basidia with subulate sterigmata, and small, symmetrically apiculate globose to subglobose spores.

Typus Auckland Province, Titirangi, Atkinson Park, 11.XII.l966, R. F. R. McNabb, PDD 25608.