A rapidly-growing fungus that produces a white colony within three days, when incubated at 25oC (77oF). The white colony becomes dark gray with increased incubation. It is commonly isolated in tropical and subtropical areas and rarely in temperate areas. It can be isolated from cultivated and uncultivated soils, peat bogs, salt marshes, dunes, desert soils, caves, lake bottom mud, estuarine sediments, plants, and polluted water. Rarely, it can be an opportunistic human pathogen causing pulmonary infections in immunocompromised patients.