This species is usually sterile, but is recognized by its thin whitish thallus with scattered, black, urceolate pycnidia, each surrounded by a neat, white thalline rim, which is K–, C–. The conidia are non-septate, bacilliform, c. 5–6 × 1.5 µm.
On trunk of large Quercus sp.
GB&I: England (Shropshire).
A species of veteran trees, especially oaks, in communities of the Arthonietum impolitae and Lecanactidetum premneae associations