Anamorph: not known. Teleomorph: stromata 0.5-1.5 mm diam., forming a black spot on the upper surface of the leaf, ± lenticular, slightly prominent, concealed by the host leaf hairs on the lower surface, containing a single ascoma. Ascomata perithecia, 300-400 µm diam., 120-230 µm high; neck at first 200-500 µm long, 30-60 µm diam., straight and subcylindrical, sometimes eventually reaching to 1 mm long and becoming twisted and transversely flattened when dry, emerging on either leaf surface, with some ascomata having two ostioles. Peridium 8-12 µm thick, composed of 3-4 layers of dark-walled angular cells. Interascal tissue absent. Asci (150-)185-235 x 6-7.5 µm, produced horizontally within the perithecium, cylindrical with a rounded apex, tapering at the base, apically somewhat thick-walled, with a single discernable wall, with a I- refractive apical ring, 8-spored. Ascospores sometimes lying in parallel but often twisted within the ascus, (120-)165-225 x ca 1.5 µm, filiform, tapering towards the ends, hyaline, smooth, thin-walled, 9- to 12- (to 14-) septate, not constricted at the septa, often with short disc-shaped appendages at one or both ends.