, commonly known as Ojo de gallo (Rooster's Eye) or American Leaf Spot , is a parasitic fungus responsible for one of the most destructive coffee diseases in Latin America. Unlike most Mycena species, which are harmless decomposers (saprobes), M. citricolor is a specialized plant pathogen. It primarily affects Coffea arabica , where it can cause yield losses ranging from 20% to 90% depending on environmental conditions. Key Characteristics & Biology
The disease is identified by circular, brown lesions on coffee leaves, stems, and fruits. As the spots mature, they turn straw-colored and often develop small, yellow, hair-like structures called gemmifers . Ojo de gallo Mycena citricolor
While most damaging to coffee, it can infect over 550 plant species across 80 families, including avocado, citrus, and various weeds, which often serve as "hidden" reservoirs of the pathogen. Environmental Impact & Distribution , commonly known as Ojo de gallo (Rooster's
It is found throughout Latin America, including Costa Rica, Guatemala, Mexico, Colombia, and Brazil. It primarily affects Coffea arabica , where it