Specimens Examined
NEW ZEALAND: North 1.: no data, P. K. Buchanan, 1993 (PDD 63797); Northland: Waipoua Forest, Marlborough Rd, on decayed log of ?Melicytus, P. K. Buchanan 93/030, 20 May 1993 (PDD 63359); Bay of Plenty: Mt Te Aroha, on Metrosideros robusta, G. H. Cunningham, 19 June 1957 (PDD 20252 (holotype), PDD 20253 and 20254, all as Grifola campyla); Rotorua: Whakarewarewa State Forest, Cpt 11, on Eucalyptus fastigata, J. W. Gilmour, 27 May 1980 (NZFRI 3130, as Grifola rosularis); Whakarewarewa Forest, on stump, D. Cross, 3 May 1988 (NZFRI 3251, as G. rosularis); Wellington: Kaitoke, Waterworks reserve, on dicot. host, M. Thompson, 3 May 1980 (PDD 41133, as G. campyla); Otaki Forks, on dead wood, E. H. Atkinson, July 1922 (PDD 3661, as G. campyla); Pukematawai, Tararua Ranges, on dead wood, E. E. Chamberlain, 22 Mar. 1933 (PDD 3973, as G. campyla); Erua, on Libocedrus bidwillii, G. B. Rawlings, 1940 (PDD 5660, as G. campyla); South I.: Buller: Reefton, on Nothofagus fusca, G. B. Rawlings, June 1946 (PDD 5667, as G. rosularis); Reefton, on N. fusca, E. E. Ensor, 6 June 1953 (NZFRI 1707, as Polyporus rosularis); Reefton, Staircase Creek, on N. fusca, S. D. Baker, Nov. 1952 (PDD 13375, as G. campyla); Westland: Douglas Rock, Copland Valley, 3500 ft, on Libocedrus bidwillii, G. T. S. Baylis, 31 Jan. 1947 (PDD 5079, as G. campyla); Mt Aspiring National Park, Haast Pass, Pike Creek, on fallen trunk of Nothofagus menziesii, M. Rajchenberg 10094, 8 May 1989 (CIEFAP, PDD 65317); Otago: Leith Valley, on dead wood (PDD 6514, as G. campyla).
AUSTRALIA: Victoria: Mt St Leonards, E. W. B. Da Costa, Apr. 1949 (PDD 13524, as G. campyla).

Fruit-body annual, lignicolous, compound, with several imbricate pilei or numerous pilei arising from a common base. Pilei flabelliform, up to 6 x 5 x 0.8 cm, with an attenuated, narrow base either strictly lateral or elevated, fruit-body somewhat pendent. Margin regular or irregular, slightly undulated, lacking a sterile portion both at the growing margin and in lateral parts. Pileus surface continuous laterally with the tubes, pubescent or glabrous, delicately granulose or roughly pulverulent and, in sectors, with bundles of longitudinally tightly arranged hyphae; surface longitudinally crenulated, azonate, brown, deep brown to dark umbrinous chestnut, contrasting with the white hymenial surface and the white to pale yellow lateral edges of the tubes.
Context white, up to 3 mm thick. Tubes white, up to 5 mm long. Pores regular, round, 3.5-4.5 per mm, with smooth or slightly fimbriate mouths.
Hyphal system monomitic. Generative hyphae with clamps, 5-8 µm diam. in the context, 3-5 µm diam. in the dissepiments, with hyaline walls to 1.5 µm thick, strongly metachromatic in cresyl-blue, IKI-, swelling and distorting in KOH to leave an irregular lumen that stains weakly with phloxine. Gloeopleurous hyphae 5-8 µm diam. with contents chestnut or strongly staining with phloxine.
Basidia claviform, 9-17 x 4-6 µm, 2-4 sterigmate. Spores ellipsoid, 4.0-5.5 x 2.5-3.5 µm, with an oil-like droplet in the cytoplasm and with slightly thickened, hyaline walls, IKI-; spores abundant in all collections examined. Chlamydospores globose or ellipsoid, 4-11 µm diam., with thickened walls, present in the context and the dissepiments of some specimens (PDD 13375, PDD 6015, PDD 65317; vide infra).
Wood-rot brown.

Basidiocarpus pileatus, imbricatus vel multipileatus, annuus, poroideus; pileus flabellatus, lateraliter vel dorsaliter affixus, basis attenuata, brunneus; pori 3.5-4.5 per mm albi; systema hypharum monomitica; hyphae genitoriae fibulatae, crassitunicatae, in KOH 5% difluentes metacromaticaeque; basidiosporae ellipsoideae, hyalinae, leviter crassitunicatae, 4.0-5.5 x 2.5-3.5 µm; carie brunnea consociata.

Etymology: The specific epithet brunnea means brown, and refers to the coloration of the pileus surface.
Remarks: Cunningham (1965) refered material of P. brunnea to two species that he described in the genus Grifola, G. campyla (Berk.) G.Cunn. and G. rosularis (G.Cunn.) G.Cunn. His descriptions of both of these species were based in part on specimens of P. brunnea. By comparing an isotype specimen (PDD 28027) of G. campyla (basionym: Polyporus campylus Berk. (Berkeley 1860)) and the holotype (PDD 3914) of G. rosularis (basionym: Polyporus rosularis G.Cunn. (Cuuningham 1948)), it was concluded that these species are conspecific. The recombinatiom Ryvardenia campyla (Berk.) Rajchenb. (Rajchenberg 1994) is accepted.
Ryvardenia campyla differs from P. brunnea in its dimidiate to flabelliform pilei, the white to very pale brown coloration of the pileus surface, and the pinkish-beige marginal area of way texture when fresh. Also, the upper pileus surface has a poroid sterile structure towards the base. Generative hyphae in R. campyla are thin-walled and sclerified and then refractive in KOH; they do not swell in KOH, and are not metachromatic in cresyl-blue. The dissepiments are dimitic with skeletal hyphae. Spores are hyaline and slightly larger than those of P. brunnea, 4.6-6.5 x 3.7-4.5 µm.
Postia brunnea appears to be closely related to P. pelliculosa (Berk.) Rajchenb. (Rajchenberg 1988). The species have spores of similar shape and with somewhat thickened walls. The latter character is unusual in Postia Fr., where most species have thin-walled spores (Julich 1982). Postia pelliculosa differs from P. brunnea in its solitary, dimidiate and thickly strigose pelei, sterile margin, pinkish-ochraceous context and slightly larger spores, 5-7.5 x 3-4 µm. For a description of P. pelliculosa see Cunnginham (1965) (under Tyromyes), Buchanan & Hood (1992), Hood (1992), Marks et al. (1982) (under Tyromyces) and Wright and Deschamps (1972) (as Spongipellis chubutensis Wright & J.R.Deschamps).
Hood (1992) included a brief description and line drawings (figs 84a-e) of P. brunnea, as Grifola sp. Hood's fig. 84a is a habit drawing of NZFRI 3251, somewhat atypical because the pelei are immature with pores poorly developed. The fungus photographed in fig 84 (plate 5) appears to be a different species.

Holotypus PDD 20252.