Anamorph: conidial stroma with a white to gray disc, sometimes with a dark border, circular to irregular, rounded or flat, with 1-4 black ostioles located in the centre or to one side. Conidial locule one per stroma, composed of numerous irregular or radiating chambers lined with thin-walled angular cells, from which the conidiophores arise. Conidia 3-6 x 0.75-1 µm, allantoid, aseptate, hyaline, thin-walled. Teleomorph: stromatal disc chalky white to light gray, furfuraceous, circular to irregular, flat, prominent or rarely reduced, to 700 µm diam. Ascomata forming conical or rounded protuberances on the bark surface. Ectostroma usually well-developed in the upper regions. Entostroma normally limited to the region near the perithecial walls. Ostioles clustered or scattered in the centre of the disc. Perithecia circinate, 2-10 (-15) per stroma, 300-500 µm diam. Asci 30-65 x 6-10 µm. Ascospores 8-20 x 2-4 µm.