Ascomata 120-200 µm diam, ± spherical to ovoid, olivaceous to dark grey, with well-developed brown rhizoids. Peridium thin-walled, composed of brown angular cells 8-14 µm diam, with dimorphic hairs formed from the upper part. Hairs either seta-like, 5-6 µm diam at the base, thick-walled, long and tapering and smooth to warted; or short, narrow, strongly verrucose and repeatedly dichotomously branched. Interascal tissue none, at least at maturity. Asci 22-32 x 8-12 µm, clavate, evanescent at an early stage, 8-spored. Ascospores 6-7.5 x 4-5.5 µm, ovoid, often bilaterally flattened, brown and relatively thick-walled when mature, with a germ pore at the attenuated end and sometimes a pale spot at the other end.
Colonies growing rapidly, the aerial mycelium grey or white and sometimes with a yellow reverse.