Anamorph: not known.
Teleomorph: stromata absent. Ascomata perithecia, 100-150 µm diam., globose, black, becoming concave when dehydrated. Neck central, to around 300 µm long and 60 µm diam., often curved and generally flattened when dry, surrounded by a white powdery crown-like structure at the base of the neck. Peridium 25-35 µm thick, formed of 6-7 layers of thin-walled flattened cells. Interascal tissue not known. Asci 40-50 x 7-10 µm, fusiform, with a conspicuous refractive apical ring ca 3 µm in diam., 8-spored. Ascospores biseriate or in two clusters, 19.7-25 x 2.6-3.2 µm, narrowly fusiform, straight and pointed, with a median septum and short gelatinous appendages at each end.
Not formally assessed. Only reported once from GB&I, but potentially under-recorded.
In petioles of dead overwintered leaves of Carpinus betulus.
VC17 (Surrey/ W Sussex borders).