Diatrype stigma

Scientific name:  Diatrype stigma (Hoffmann:Fries) Fries
Derivation of name:  Stigma means "a spot" perhaps in
reference to the tiny "spotlike" bumps of the perithecia.
Synonyms:  
Common name(s):  
Phylum:   Ascomycota
Order:   Xylariales
Family:   Diatrypaceae
Occurrence on wood substrate: Saprobic; forming sheet-like
growths on decaying hardwood branches; year-round.   
Dimensions:  The black crusts of this fungus are variable in
shape and are up to 23 cm or more long and 1-1.5 mm thick.  
Description: The blackish-brown to black surface is shiny,
finely roughened to smooth, and sometimes minutely cracked.
Tiny bumps on the surface indicate the locations of perithecia
embedded in a white flesh.      
Edibility: Inedible.  
Comments:  This is a common fungus on beech branches where
the fungus often encircles the branch. The fungus gives the
impression that the wood is burned. 

Figure 1. Diatrype stigma on wood. Photo © Dianna Smith
 

Figure 2. An old specimen of Diatrype stigma.

Figure 3. When magnified with a hand lens, the tiny
bumplike pores of the embedded perithecia can be
seen all over the surface of the fungus.