Anamorph: conidiomata 1-2 x 0.3-0.5 mm. Conidiophores 10-12 x 2.5-3 µm. Conidia 6-8 x 2.5-3 µm.
Teleomorph: Stromata as numerous longitudinally elongate blackened areas 0.5-1 x 0.1-0.2 mm, often with a central light-coloured ectostromatic disc. Ascomata 150-300 µm diam, necks emergent, fused together. Asci 30-40 x 5-7 µm. Ascospores 8-10 x 1.5-2 µm, without appendages.
Description contributed by Graham Kinsey, CABI. The placement of this species is uncertain, and no molecular data are available. It has also been included in Cryptodiaporthe, a genus now considered a synonym of Plagiostoma.