Annual effused-reflexed stereoid fungus. [Spreading up to 14 cm.] Upper side white, hairy, sulcate, [projecting up to 2 cm]. Underside white to cream to gray [or ochre in age], wrinkled (merulioid). Microscopic features: hyphae without clamps. A few hyphae with small incrustations. The underside may turn pinkish orange after storage in a herbarium (or at least under Dan's desk).
The common Irpex lacteus has underside with jagged pores to flat teeth (microscope: encrusted cystidia). Plicatura nivea is a northern species on alder (Alnus).
Saprobe on dead hardwoods, causing a white rot.
April, July, October to early December for the known Chicago Region records. Elsewhere it is recorded throughout the year, though less in summer. Mostly winter and spring in the West.
Widely distributed, apparently worldwide. For North America it is reported on Mushroom Observer from the West Coast and Arizona though there are herbarium records for most of the continent. Rare in the Upper Midwest (outside of Kansas) or seldom collected and identified, or records not online.
Chicago Region status
Uncommon; ten records over 20 years. This species was first determined in 2013 (PRL 10675, dry mesic oak savanna) but a 2012 collection (PRL 11502, oak-hickory woodland) has since been identified, both from McHenry County. A third location in the county was added October 2014. A returned loan included 2 specimens from 1999, Cook County, and 2004, Dekalb County, identified by Karen Nakasone. It was seen again in Cook County in 2015 and 2017, McHenry County in 2016, and DuPage County in 2017. The nearest historic collection is a July 1910 Harper collection from Blue Mounds, Dane County, Wisconsin, and is the only collection on MycoPortal for Wisconsin. The only Illinois collection that was online MycoPortal was made by Epling in 1923 from Jacksonville, Morgan County.
I first learned of this species at the 2012 NAMA foray in California where we made two collections (NAMA 2012-281, NAMA 2012-336) and Tom Bruns and Karen Nakasone held a corticioid workshop. Tom Bruns calls it the band-aid crust. This allowed me to recognize it the next year in Illinois.
Taxon Details and Links
Byssomeruliuscorium(Pers. : Fr.) Parmasto,
Eesti NSV Teaduste Akadeemia Toimetised Bioloogia 16(4): 383 (1967)