Generic short diagnoses:
Tiny to small, barrel- to disc-shaped operculate discomycetes with a hymenium dotted by dark, free spores in protruding, amyloid asci. On dung, soil and debris.
The picture originates from the MycoKey 2.0 DVD. Here you will also find a larger picture along with a detailed generic description, references and an interactive, synoptical key to genera.