Stromata as numerous pustules 0.1-1 mm diam, papillate; ectostromatic disc slight, minute, greyish; containing ascomata in definite but loose groups. Ascomata perithecial, 240-440 µm diam, necks 80-90 µm wide at the apex, stout, separate, scarcely emergent. Peridium 18-25 µm thick. Asci 40-50 x 8-11 µm. Ascospores 13.5-17.5 x 2.5-5 µm, sometimes curved, becoming constricted at the septum with maturity, often 4-guttulate, sometimes with minute filiform appendages.
Description contributed by G. Kinsey (IMI). Holm & Holm (1991) described an anamorph in culture with thick-walled 1-septate yellowish conidia 13-16 x 3.5-4 µm in size. Mejía et al. (2011) note that a LSU sequence of this species suggests that it is not congeneric with the type of Cryptodiaporthe (here placed into synonymy with Plagiostoma) but an alternative generic placement was not provided.