Hypoxylon fuscum

A species infecting wood of several hosts such as Alnus, Corylus, Betula, Salix, or Carpinus.

Asci cylindrical, uniseriate, 8-spored, up to 170 µm long and 8-12 µm wide, with spores concentrated in the upper half of the ascus, and an amyloid apical apparatus.

Paraphyses filiform, slender, hyaline, septate, projecting slightly above the level of the asci.

Ascospores ellipsoidal, flattened on one side, very dark brown, smooth-walled, with a straight to slightly sinuous germ slit extending the entire spore length, and a perispore dehiscent in KOH.