Ascomata perithecial, ± spherical, black, 90-110 µm diam with a very short neck, the ostiole visible from the surface as a minute black spot surrounded by a clypeus 100-150 µm diam. Peridium 6-7 µm thick, composed of 2-3 layers of flattened cells. Asci 40-60 x 7-11 µm, clavate-ellipsoidal, with a conspicuous refractive apical ring ca 2 µm diam, 8-spored. Ascospores 10.5-16 x 3.2-4.5 µm, elliptical, often slightly inaequilateral with one face ± flat, hyaline, aseptate, thin- and smooth-walled, the contents appearing granular, without a gelatinous sheath or appendages.
Anamorph: Monostichella robergei. Conidiomata acervular, inserted between the epidermis and the cuticle, 60-220 µm diam. Conidiogenous cells short, ± isodiametric, 6-9 x 5-7 µm, proliferating percurrently. Conidia 13-15 x 6.5-7.5 µm, ovoid, hyaline, aseptate.