Fungi associated with coffee rust Hemileia vastatrix and the description of two new species

Coffee leaf rust, caused by Hemileia vastatrix, continues to pose a severe threat to coffee production in Mexico and globally. In response, the search for sustainable, ecologically based control strategies has turned toward mycopathogenic fungi as natural antagonists of plant pathogens. This study reports the isolation and characterization of 27 mycopathogenic fungal strains resembling Lecanicillium and Verticillium spp. from H. vastatrix pustules in the Mexican states of Chiapas, Colima, Nayarit and Veracruz. Detailed morphological and molecular analyses revealed two novel species (Akanthomyces hemiliae-vastatricis sp. nov. and Akanthomyces jabaliensis sp. nov.) as well as a new national record of Akanthomyces uredinophilus. The detection of Simplicillium lanosoniveum, a key natural antagonist of coffee rust, further underscores the ecological complexity of fungal interactions within coffee agroecosystems. These findings enrich the understanding of mycopathogen diversity associated with H. vastatrix and support the integration of native fungal strains into biological control frameworks, offering a promising path toward more resilient coffee cultivation systems.