Specimens examined: Holotype: 11474, on Brachyglottis repanda J. R. et G. Forst., May 1952, G. H. Cunningham, Hicks Bay, Aukland, New Zealand, in herb. PDD. USA: LOUISIANA - RLG 13549, on Ulmus rubra Muhl., Baton Rouge Parish (ARIZ, CFMR).

Basidiocarp broadly effuse, up to 15 x 2.5 cm in extent, up to 150 µm thick, membranous, tightly adherent; fertile area continuous, smooth, not cracked, "yellowish white" (3A2) to "dull yellow" (3B4); margin up to 0.25 mm wide, thinning out, fibrillose, irregular in outline, white. Hyphal system monomitic. Subiculum a textura intricata, hyphae 3.5-5.5 µm diam, thin walled or firm walled, hyaline, long celled, simple septate, smooth; subhymenium a compact textura intricata porrecta, hyphae 2.5-3.5 µm diam, thin walled, hyaline, short celled, simple septate; cystidia lacking; basidia clavate with slight median constriction, (27-)35-40 x 6.5-8.5 µm, thin walled, hyaline, 4-sterigmate, sterigmata up to 5 um long; basidiospores narrowly ellipsoid, (7-)8-9.5 x 3.5-4.5 µm, hyaline, thin walled, smooth, Melzer's -, acyanophilous.

Known only from New Zealand and Louisiana.

On hardwood branches; associated with a white rot.

Discussion: Phanerochaete corymbata is similar to P. auratum, P. tuberculata, and P. xerophila. It differs from P. auratum that has hyphae more than 6 µm wide and wider spores 7.5-9 x 4.5-5.5(-6) µm. Phanerochaete tuberculata has a fibrillose to nearly cordonic basidiocarp, some nodose septate hyphae, and basidiospores 6-7.5 x 3.5-4.5 µm. Phanerochaete xerophila has basidiospores 6-8 x 3.5-4.5 µm giving them a more broadly ellipsoid shape than in P. corymbata.
This species has been collected recently in Louisiana, the first time since its original collection. This results in an unusual distribution for this poorly known species. The second specimen differs from the type only in possessing a highly cracked fruiting body and hyphae encrusted with hyaline crystals.

Brachyglottis repanda Forst. Auckland: Hick's Bay, 300ft., May, 1952. G.H.C., type collection, P.D.D. herbarium, No. 11474. Pittosporum sp. Auckland: Whakapapa, Mt. Ruapehu, 3,000ft., October, 1949, J.M. Dingley.

Hymenophore annual, adnate, membranous, effused, forming linear areas to 40 x 3 cm. with numerous outlying islands; surface cream, even, not creviced; margin thinning out, white, arachnoid, adnate. Context white, 40-80 µ thick, composed of a narrow basal layer of parallel hyphae, and an intermediate layer of erect hyphae sparsely branched below, freely branched (corymbose) beneath the hymenium; generative hyphae 4.5-5 µ diameter, wall 0.5 µ thick, naked or occasional hyphae coated with fine crystals, hyaline, septate, without clamp connections. Hymenial layer to 40 µ deep, of basidia and paraphyses compacted into a dense palisade. Basidia subclavate, slightly projecting, 16-20 x 4-5 µ, 4-spored; sterigmata slender, to 4 µ long. Paraphyses subclavate, similar to the basidia but narrower. Spores obovate or elliptical, with rounded apex and acuminate base, 6-7 x 3-3.5 µ, apiculate, wall smooth, hyaline, 0.2 µ thick.

DISTRIBUTION. New Zealand.

Hymenophorum membranaceum, adnatum, effusum; superficie cremea aequa, non rimosa. Hyphae contextus in corymbis ordinatae, afibulatae, 4.5-5 µ diam., nudae. Basidia 16-20 x 4-5 µ, 4 sporis. Sporae obovatae vel ellipticae, 6-7 x 3-3.5 µ, laeves, hyalinae.

In the type collection the hymenophore is closely adnate, with an even, non-creviced cream surface, thin context with hyphae scantily branched below, corymbose beneath the hymenium, arising from a narrow basal layer of parallel hyphae, naked save for occasional hyphae which are finely crystal coated. The collection from Pittosporum differs in that the fructification is loosely attached, has a deeply creviced surface, hyphae are thinner, with thinner walls, and the basal layer is stouter. Occasional hyphae bear crystals, but most are naked. When further collections come to hand it may prove to be distinct.

Auckland: Hick's Bay, 300ft., May, 1952. G.H.C., type collection, P.D.D. herbarium, No. 11474.

Basidiome thin membranaceous. Hymenial surface cream-coloured to pale yellowish. Subicular hyphae hyaline, thin- to slightly thick-walled, 2.5-4.5 µm wide, without clamps, often branching at right angles. Subhymenial hyphae thin-walled, 2.5-3.5 µm wide, often sparsely covered with crystalline material. Basidia clavate to subcylindrical, 18-28 X 4-5 µm. Spores hyaline, thin-walled, smooth, navicular to narrowly ellipsoid, rarely subcylindrical, 6.5-7.5(-8) X 2.5-3 x 3-3.5 µm.

The species takes an intermediate position between Ceraceomyces Jlich and Ceraceomerulius (Parm.) J. Erikss. & Ryv. Despite the absence of clamps it is placed in the former genus because of the structure of the basidiome. The type of rot is indistinct.