1) Class 2) Class pyrenomycetes 
Class of Ascomycotina, traditionally based on taxa with perithecioid ascomata that are ascohymenial in ontogeny and have unitunicate asci, often with an apical annulus. 
Pyrenomycetes is a family of ascomycetous fungi with flask-like fructifications. open at the top for the discharge of the spores. Some species are parasitic on plants, others on insect larvae, while several species are saprophytes.
[n] - class of fungi in which the fruiting body is a perithecium
class Pyrenomycetes noun class of fungi in which the fruiting body is a perithecium; includes powdery mildews and ergot and Neurospora