MATERIAL STUDIED (SELECTED): New Zealand, Westland, Lake Mapourika, on Coprosma, J.M. Dingley, XI.1946, PDD 5252 (holotype of Poria coprosmae); Stewart Island, vic. Halfmoon Bay, Ackers Point, Scenic Walk, on wood on ground, P.K. Buchanan 85/181, 24.Apr.85, PDD 53813; Auckland, Waitemata, Waitakere Ranges, Spragg Track, M. Rajchenberg 10020, 11.Apr.89, BAFC; ibid., Winstone Track, on Olearia furfuracea, M. Rajchenberg 10034, 11.Apr.89, BAFC; Coromandel, Port Charles, track between Stony Bay and Fletcher Bay, M. Rajchenberg 10039, 22.Apr.89, BAFC.
CULTURES STUDIED: BAFC/cc 531, from specimen M. Rajchenberg 10020; BAFC/cc 561, from specimen M. Rajchenberg 10034; BAFC/cc 463, from specimen M. Rajchenberg 10039 (above).

REMARKS: This is the correct epithet for the specimens named as Tyromyces chioneus (Fr.) Karst. by Cunningham (1965), who stated that his fungus was the same one treated as Polyporus semipileatus Peck by Overholts (1953) from North America, and now widely accepted as a synonym of S. nivea (David 1982; Gilbertson & Ryvarden 1987). Cunningham (1965) himself realised that his Poria coprosmae G.H. Cunn. was the same taxon, but he incorrectly used the name Tyromyces chioneus, which is a different taxon, as stated by Buchanan & Ryvarden (1988). The latter authors, in their type studies of polypores described by G.H. Cunningham (Buchanan & Ryvarden 1988), were of the opinion that Poria coprosmae was a distinct taxon and placed it in Ceriporiopsis Dom. My own studies of the holotype, other herbarium material, freshly collected materials, and cultural studies lead me to support Cunningham's (1965) view.
The species has a dimitic or semi-trimitic hyphal system with clamped generative hyphae, arbuscular "binding hyphae" that are branched, solid and lateral processes of the generative hyphae, and skeletal hyphae (Fig. 9B-D). Buchanan & Ryvarden (1988) depicted these solid binding processes indicating that a "careful examination of the thick-walled `binding' hyphae shows the occasional clamp". They did not mention the presence of skeletal hyphae but I found them in the holotype of P. coprosmae as well as in other specimens studied. The holotype contains several fruit bodies. In some of them skeletal hyphae are lacking in the dissepiments but they are found in other fruit bodies of the collection. The same situation was found in other specimens studied. This is not strange, as typical specimens of S. nivea are devoid of skeletal hyphae in the dissepiments (David 1982; Gilbertson & Ryvarden 1987). In the context, however, they are commonly found, as in PDD collections of P. coprosmae including the holotype. Pyramidic crystals on generative hyphae in the dissepiments of S. nivea were said to be absent in the holotype of P. coprosmae (Buchanan & Ryvarden 1988). Nevertheless, I was able to find them regularly in some fruit bodies of this collection (Fig. 10) as well as in many other collections. The spores of P. coprosmae are also typical of S. nivea (Fig. 9E).
Cultures of P. coprosmae showed similar features to those described for S. nivea (Nobles 1965; Bakshi et al. 1969; Stalpers 1978; David 1982). In brief: growth of the mycelium is very slow, oxidase reactions are positive, the generative hyphae become irregularly thick walled and may develop sclerified lateral arbuscular branches. Fibre hyphae are also formed as well as contorted, encrusted, and sclerified hyphal tips (Fig. 11). The sexuality is tetrapolar.