Coprosma australis (A. Rich.) Robinson. Wellington: Ohakune, 2,000ft.. December, 1953, J.M. Dingley. Coprosma robusta Raoul. Auckland: Campbell's Bay, July, 1953, J.M. Dingley. Griselinia lucida Forst. f. Taranaki : Mt. Egmont, 2,500ft., March, 1951, J.M. Dingley. Metrosideros robusta A. Cunn. Auckland: Mt. Te Aroha, 2,750ft., November, 1946, G.H.C. Nothopanax colensoi (Hook. f.) Seem. Auckland: Mt. Hauhangatahi, 2,800ft., February, 1952, G.H.C., type collection, P.D.D. herbarium, No. 11350. Taranaki Mt. Egmont, 3,000ft., March, 1951, .J.M. Dingley. Wellington: Obakune, 2,000ft., December, 1953, J.M. Dingley.

Hymenophore annual, closely adnate, ceraceous, effused, forming linear areas to 30 x 6 cm.; surface rich cream to pallid yellow ochre, even, not creviced; margin thinning out, definite, cream, even, byssoid. Context 10-50 µ deep, white, composed of a few basal hyphae and an intermediate layer of mainly vertical hyphae; generative hyphae 2-3.5 µ diameter, wall 0.2 µ thick, naked, branched, septate, without clamp connections, sometimes inflated near septa. Hymenial layer to 70 µ deep, of basidia, paraphyses and gloeocystidia. Basidia subclavate, 20-24 x 5^-6 µ, projecting, 2-4-spored; sterigmata slender, 6-8 µ long. Paraphyses clavate, shorter than the basidia. Gloeocystidia of two types: (a) arising in the sub-hymenium, aculeate, apex long-acuminate, 15-40 x 5-6 µ, projecting; (b) arising from the base of the context, flexuose-cylindrical, 40-80 x 6-8 µ, with rounded base and apex, some passing into the hymenium but not projecting, wall 0.25 µ thick. Spores globose or subglobose, apiculate, 4-6 x 4-5 µ, wall smooth, hyaline, 0.2 µ thick.

DISTRIBUTION. New Zealand.

HABITAT. Effused on decorticated wood.

Hymenophorum ceraceum, adnatum, effusum, superficie cremea vel pallide ochracea, non rimosa. Hyphae contextus afibulatae, 2-3.5 µ diam., nudae. Basidia 20-24 x 5-6 µ, 2-4 sporis. Gloeocystidia strati hymenialis, longo-acuminata, contextus cylindricale flexuosa, 40-80 x 6-8 µ. Sporae globosae vel subglobosae, apiculatae, 4-6 x 4-5 µ, laeves, hyalinae.

Characterized by the two types of gloeocystidia, small globose smooth spores, absence of clamp connections, and widely effused, adnate, pallid ochre, thin and even hymenophore closely appressed to naked wood. Gloeocystidia of the hymenial layer are long-aculeate and project for about half their length. Because of their size, shape and position the species might be sought under Peniophora; without justification, however, since these bodies are true gloeocystidia with naked exterior and oily yellow contents. Those of the context are flexuous-cylindrical with rounded ends, often bent at an angle or allantoid and also contain oily yellow contents. Gloeocystidia may be abundant or scanty in different collections; sometimes the aculeate form may be wanting. All structures of the hymeniam are filled with conspicuous oil globules and each spore contains a large globule, sometimes almost filling the interior. Plants are so readily devoured by snails or insects that it is usually difficult to secure a fertile specimen for examination - hence the specific name.

Auckland: Mt. Hauhangatahi, 2,800ft., February, 1952, G.H.C., type collection, P.D.D. herbarium, No. 11350.

Basidiome subinvisible when dry, probably pruinose when fresh, about 60 µm thick. Hyphae hyaline, thin-walled, 1.5-3 µm wide, without clamps. Gloeocystidia clavate, 20-40 x 5.5-9.5 µm, amyloid, with pale yellowish contents, sulpho-positive. Cystidia hyaline, acuminate, 15-40 x 4-6.5 µm, tapering towards the top, rarely abruptly narrowed. Basidia hyaline, clavate to suburniform, sometimes stalked, 15-30 x 6-7.5 µm, amyloid, with 2-4 sterigmata. Spores hyaline, thin-walled, smooth, globose to subglobose, (5-)5.5-6.5 X (4.5-)5-6 µm, amyloid.

Macroscopically, the species appears close to Xenasma Donk or Tubulicrinis. However, pleurobasidia are absent and, although amyloid- basidia and hyphae do occur in Tubulicrinis, the absence of thick-walled, multi-rooted lyocystidia does not permit the inclusion of the species in Tubulicrinis. The presence of two kinds of cystidia and the smooth, globose spores might indicate a relationship to Vesiculomyces Hagstrõm, but there are some obvious differences (amyloid hyphae and basidia, sulpho-positive gloeocystidia, and very thin basidiome). The species causes a weak white rot and is tentatively placed in Gloeocystidiellum Donk rather than in a new monotypic genus.

Geographic and host distribution. Amylofungus corrosus is known only from New Zealand. According to Cunningham (1963), specimens of this species have been collected from several families of deciduous trees.

Basidiomata resupinate, effuse, ceraceous, 40-120 µm thick. Hymenial surface yellow, smooth. Monomitic. Subiculum thin, with compact texture, hyphae colorless, 1.5-3 µm, thin-walled. Subhymenium ± thickening. Gloeocystidia irregularly cylindrical or clavate, sometimes long-acuminate toward apices, 20-60 x 6-12 µm, thin-walled, amyloid, SA+. Basidia utriform, 33-43 x 5-7 µm, four-sterigmate, amyloid. Basidiospores globose to subglobose, smooth, thin-walled, 5.5-6.5(-7) x 4.5-5.5 µm, amyloid.

This description is based on the holotype (see also Cunningham, 1963; Stalpers, 1985).
This species was tentatively placed in Gloeocystidiellum by Stalpers (1985), but Gloeocystidiellum s. s. has clavate basidia and ornamented basidiospores. The basidioma of the type specimen (PDD 11350) has been largely destroyed; it was probably eaten by invertebrates attracted by the fragrant gloeocystidia. This attraction was also mentioned by Cunningham (1963, p. 58).

Specimen examined. NEW ZEALAND. AUCKLAND: Mt. Hauhangatahi, 900 m, on Neopanax colensoi, Feb. 1952, G.H. Cunningham (PDD 11350, HOLOTYPE).