Stromata appearing as scattered, ± circular, low or truncate-conical pustules erumpent through host bark, exposing a well-developed black-brown to greyish ectostromatic disc 0.2-2.0 mm diam through which the perithecial necks emerge, darkened area somewhat extended beneath the host bark; entostroma well-developed, brownish, composed of hyphae and rounded-angular cells intermixed with host cells and angular crystals, sometimes poorly developed beneath the ascomata, containing a cluster of perithecia in the lower part, lacking any distinct zone lines within the substrate.
Ascomata 200-500 µm diam, perithecial, globose or mutually deformed, with long necks, black, upright to oblique; necks 250-700 µm long, convergent or remaining separate, with just the upper part emergent, formed in clusters in the lower part of the entostroma. Peridium composed of brown, thick-walled, rounded-angular cells at the exterior, merging into an interior layer of compressed, hyaline cells, neck composed of elongate, brown, thick-walled cells. Interascal tissue composed of paraphyses, broad, ribbon-like at first but soon disappearing, the neck periphysate. Asci 50-73 x 7-12.5 µm, clavate to cylindric-clavate, the apex somewhat truncate, thick-walled particularly in the upper half, with a single discernable wall layer, 8-spored, with a refractive J- apical ring, becoming detached within the perithecial cavity. Ascospores 11-16(-18) x 2-3(-5.5) µm, narrowly ellipsoidal to near fusiform, often tapering slightly more at one end than the other, straight to slightly curved, hyaline, 1-septate, the septum usually median but sometimes dividing the spore nearly 2:1, slightly constricted at the septum, smooth, often with a small cylindrical hyaline appendage at each end.
Anamorph: Fusicoccum-like. Conidiomata formed in locules 0.5-1 mm diam within the stroma, often towards the periphery, with a poorly defined wall. Conidiophores filiform, hyaline, septate, smooth, irregularly branched, formed in the basal part of the locules. Conidiogenous cells cylindrical, hyaline, smooth, with a minute channel and collarette, proliferating percurrently. Conidia of two types; alpha-conidia 6.5-12.5 x 4-6 µm, ellipsoidal to ovoid, acute at one end and obtuse at the other, hyaline, simple; beta-conidia 9-19 x 1.5-3 µm, cylindrical to fusiform, straight or curved, hyaline, simple, smooth.