The Stachybotryaceae are a family of fungi in the order Hypocreales; the genera it contains have been described as "hyper-diverse".

Stachybotrys is a genus of molds, hyphomycetes or asexually reproducing, filamentous fungi, now placed in the family Stachybotryaceae. The genus was erected by August Carl Joseph Corda in 1837. Historically, it was considered closely related to the genus Memnoniella, because the spores are produced in slimy heads rather than in dry chains. Recently, the synonymy of the two genera is generally accepted. Most Stachybotrys species inhabit materials rich in cellulose. The genus has a widespread distribution and contained about 50 species in 2008. There are 88 records of Stachybotrys on Species Fungorum, of which 33 species have DNA sequence data in GenBank. Species in the genus are commonly found in soil, plant litter and air and a few species have been found from damp paper, cotton, linen, cellulose-based building materials water-damaged indoor buildings, and air ducts from both aquatic and terrestrial habitats.