Anamorph: conidiomata immersed in pale necrotic areas of the thallus surrounded by a black zone line, 50–100 μm diam., ± spherical to broadly oblate, black in external appearance. Peridium 9–15 μm thick, brown, darker in the ostiolar region, composed of 3–5 layers of cells 3–9 μm diam., the inner cells hyaline. Conidiogenous cells 5–9×3–4.5 μm, ampulliform, proliferating percurrently. Conidia (3.5-) 4-5 (-6) x 3-4 µm, widely ellipsoidal to subspherical, with one large or rarely two smaller guttules, hyaline, aseptate, smooth- and thin-walled, without a gelatinous sheath or perispore. Teleomorph: not known in GB&I. Stromata absent. Ascomata dispersed, developing in necrotic areas of the host thallus, visible as black dots often with a paler apical region indicating the ostiole; 200–250 μm diam., ± spherical or broadly oblate with a weakly papillate ostiolar region. Peridium 15–20 μm thick, brown, consisting of 3–4 layers of cells 5–10 μm diam. Interascal tissue of cellular pseudoparaphyses 1–2.5 μm diam., within hymenial gel that does not stain in iodine. Asci 70–100 × 7.5–10.5 μm, narrowly cylindrical, fissitunicate, laterally thickened when young, apically thickened when mature, with a small ocular chamber, wall I– and K/I– except for a dextrinoid reaction of the cytoplasm, 8-spored (but often with fewer spores reaching maturity). Ascospores ± uniseriate or partially biseriate, 11.5–15 × 4–5.5 μm, medium to dark brown, (1–)2(–3)-septate, the middle cell slightly wider than the end cells, slightly constricted at the septa, torus indistinct, distinctly verruculose, without a separate perispore, gelatinous sheath or appendages.