prl10675 prl11502

Byssomerulius corium (Pers. : Fr.) Parmasto

Eesti NSV Teaduste Akadeemia Toimetised Bioloogia 16(4): 383 (1967)

netted crust; band-aid crust
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).
Similar species:
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.
Europe ?
Specimens examined:
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.
Description links:
California Fungi ; Abney Fungi, London UK - Photos on Flickr.
Records online:
Mushroom Observer ; MycoPortal
Taxon links:
327227 MycoBank ; Index Fungorum ; Species Fungorum

See the ecology and description on Mycobank taken from Mycotaxon paper: Zmitrovich, Ivan V., Wjacheslav A. Spirin & Solomon P. Wasser. Variability of Byssomerulius corium in the Mediterranean. Mycotaxon 97: 83-90. 2006.