The Leotiomycetes are an important class of ascomycete fungi and include many plant pathogens, like the powdery mildews. The fruiting bodies are cup-shaped (apothecia) or closed (chasmothecia) and may be brightly coloured. They vary in size from golfball-size to tiny, closed ascomata with one or several asci. Today, the characterization of the Leotiomycetes is based on their genetic structure.
This page only deals with plant pathogens. For other groups of Leotiomycetes in the system see
The following orders and groups are here included: