Description contributed by Graham Kinsey, CABI; based on Wehmeyer (1933).
Anamorph: Phomopsis sp. Alpha-conidia 6-8 x 2.5 µm, cylindrical to cylindric-fusiform; beta-conidia 11-15 x 1.5 µm.
Teleomorph: Stromata visible on the host surface as scattered pustulate, circular or laterally elongated, blackened, ectostromatic discs, 0.5-2 x 0.2-1 mm, the flat blackened discs contain scattered ostioles or are nearly obliterated by a dense fascicle of ostioles, entostroma well-developed. Ascomata 250-400 µm diam, spherical to ovoid, definitely clustered beneath the ectostroma, ostioles papillate to conical or when in a fascicle occasionally much elongated and bent. Asci 37-45 x 6-9 µm, clavate, short-stalked, with a conspicuous refractive apical ring. Ascospores 11-15(-16) x 2-3(-3.5) µm, fusiform, slightly constricted at the septum at maturity.
The ascospores of this species are slow to mature and most specimens show immature ascospores without septa or constriction.