Opegrapha brevis

Thallus absent (lichenicolous on Crutarndina petractoides). Ascomata scattered or somewhat clustered, black, not pruinose, at first shortly lirellate with a slit-like disc, but the disc soon widely expanded and ascomata becoming elliptical or disciform, 0.14–0.46 × 0.12–0.24 mm, 0.1–0.14 mm high; exciple well-developed laterally, 23–30 µm thick, brown-black, K+ greenish, at the base narrower and more irregular; epithecium dilute fuscous brown, K–; hymenium 45–60 µm tall, colourless, I+ blue or, in the lower half, reddish; paraphysoids sparingly branched, 1.7–2 (–2.7) µm thick, widening to ca 3.5 µm in the epithecium; asci clavate, 38–50 × 12–15 µm, with a minute dark amyloid apical ring, 4-spored at maturity; ascospores 3-septate, the upper two cells slightly wider, ends obtuse, colourless or becoming brown due to deposition of minute pigment granules in the sheath, (14–) 15–18 × 4.5–5 (–6) µm. Pycnidia inconspicuous, ± immersed, 50–70 µm diam.; conidia cylindrical, straight, 5–7 × ca 0.8 µm.

The species should be placed in the Lecanographaceae close to Phacographa according to Frisch et al. (2014), but an appropriate generic placement is not available.