Abstract
The antigenic relationships among Phialophora verrucosa, Fonsecaea pedrosoi, and Cladosporium carrionii were studied by comparing water soluble antigens extracted from mycelia and extra-cellular antigens from culture filtrates. Immunodiffusion and immunoelectrophoresis tests detected common antigens among all 3 species, as well as antigens which appeared to be either genus or species-specific. Each test revealed more common antigens between P. verrucosa and C. carrionii than between either species and F. pedrosoi, indicating that P. verrucosa and C. carrionii are more closely related to one another than they are to F. pedrosoi. These findings provide justification for the retention of F. pedrosoi in the genus Fonsecaea.