The Myrothecium species are imperfect filamentous fungi belonging to the class Deuteromycetes. The sexual form belongs to the class Ascomycetes (Nectria). This genus contains 8 species.

Their moist colonies are black or green surrounded by a flaky white margin. The conidiophores, aggregated in superficial pads (sporodochia), bear cylindrical and densely grouped hyaline phialides. The unicellular and smooth conidia, fusiform or cylindrical, have a fan appendix.

The Myrothecium species are ubiquitous plant pathogens, but are also found on many substrates containing cellulose such as paper, cotton, textiles and plant debris. They are sometimes plant parasites with a pathogen capacity related to the production of mycotoxins (trichothecenes, Deoxytrichoverrins, etc.).

The Myrothecia have a significant industrial interest in the production of cellulase and are used as a biopesticide to control weeds and nematode population.

List of species