Xylobolus frustulatus

Scientific name:  Xylobolus frustulatus (Persoon:Fries)
Boidin
Derivation of name:  
Synonyms:  Sterium frustulosum
Common name(s):   Ceramic parchment
Phylum:   Basidiomycota
Order:   Russulales
Family:   Stereaceae
Occurrence on wood substrate:  Saprobic; clustered on
hardwood logs, particularly oak; year-round. 
Dimensions: Individual fruitbodies 0.3 to 2 cm wide.    
Description: Fruitbodies occur as crowded, polygonal, woody
plates that resemble broken pieces of tile. The fertile surface is
pinkish-buff to whitish and the outer, sterile surface is
blackish. Colonies of these fungi can cover considerable areas
of wood.      
Edibility: Not edible.  
Comments: Most commonly found on old decorticated oak
logs and stumps.

    

Figure 1. Appearance of ceramic parchment on an oak log.

Figure 2. Xylobolus frustulatus on oak.

Figure 3. Many individual fruitbodies are typically clustered
together like broken pieces of tile.

Figure 4. The light-colored surfaces bear basidia.

Figure 5. Note how tightly clustered the individual "tiles" are.
Photo © George Barron.