Annual brackets sessile, semi-globose, up to 6 cm.
May develop a stipe when fruiting on top of a log (Murrill 1903).
Upper surface smooth, glabrous, pale yellowish, cream or tan; extends as a veil-like membrane underneath creating a chamber under the pore layer, developing a hole near the base. Pore surface pale to darker brown. Pores round, 4–5 per mm.
Spores 12–16.5 × 4.5 µm, cylindric, smooth, non-amyloid. Hyphal system trimitic, with clamps. The veil is thought to retain moisture for spore production during dry summers.
Distinctive genus with a veil covering under pores.
Has some resemblance to a young Fomitopsis betulina (Piptoporus).
Causes a white rot of sapwood of conifers. Fruitbodies formed on recently dead trees. Most common on Pine (Pinus). Originally described by Peck from black spruce (Picea mariana, as Abies nigra). Also reported from fir (Abies), Douglas-fir (Pseudotsuga), hemlock (Tsuga), and tamarack (Larix).
Spores apparently dispersed by wood-boring beetles.
The persistent brackets can likely be found year round.
Throughout North America but rare in the central states, Great Plains, and southeast. Also found in South America and East Asia. MyCoportal has records for USA, Canada, Mexico, Cuba, Puerto Rico, Argentina, Brazil, Papua New Guinea, China, and Japan.
Chicago Region status
Rare. Surprisingly, there are no known historic collections or records for Illinois or Indiana. There is only one for Wisconsin (MyCoportal). It was first found in the Chicago Region in 2015.
Marengo Ridge, McHenry County, PRL 12380, 2015 June 9, on dead two-needle pine.
Taxon Details and Links
Bulletin of the Torrey Botanical Club 29: 450 (1902)
Annual Report on the New York State Museum of Natural History 27: 98 (1875)