Byssochlamys is a genus of fungi in the Trichocomaceae family. Byssochlamys spp. are historically the most widely encountered mold causing spoilage of heat processed fruits and have therefore been most extensively researched. The widespread genus contains four species, associated with food spoilage, especially heat-processed acid foods. Species of the genus Byssochlamys can produce the mycotoxin patulin, as well as byssochlamic acid and mycophenolic acid.