Description made from dried material. Sclerotia developing within or beneath the bark, visible as blackened patches on the surface of the wood where the bark has rotted away. Anamorph: not known. Teleomorph: ascomata apothecia, 1.5-3.5 mm diam., erumpent through irregular fissures in the bark, in clusters usually of 3 to 8, substipitate or clearly stalked, cupulate, the disc initially oliveaceous but becoming dark brown to black at maturity as the epithecial crystals develop, usually folded or crenulate, the margin dark reddish-brown, not pruinose, the outer wall similar in coloration to the margin and appearing minutely powdery. Ectal excipulum 50–70 μm thick at the base, 20–30(−40) μm at lower flanks and towards the margin, with an outer layer of cylindrical cells covered in a dark brown exudate and an inner part of vertically oriented globose to angular cells. Medullary excipulum 400–600 μm thick in the centre, 80–100 μm at lower flanks, of loose interwined hyaline non-gelatinized hyphae 3-5 µm diam. Interascal tissue of unbranched paraphyses 3-5 µm diam., not or hardly inflated at the apices, surrounded by brown exudate and densely covered with dark brown granules. Asci developing from croziers, cylindric-clavate, 80-120 x 5.5-7.5 µm, long-stalked (the part containing spores ca 35-45 µm in length), rather thick-walled, not fissitunicate, the apex rounded to truncate, not staining in iodine, usually 8-spored. Ascospores arranged biseriately, (5.5-) 7-8.5 x (2-) 2.5-3 µm, cylindric-allantoid, slightly to moderately curved, aseptate, hyaline, fairly thin- and smooth-walled, without a gelatinous sheath or appendages.