Which medium provides differential identification of Aspergillus species?

• A. Czapek's Agar
• B. Dermatophyte Test Medium
• C. Corn Meal Agar
• D. SABHI Agar

Answer: (A)

Differential identification relies on how species express visible growth and pigments on a defined medium. Czapek’s agar provides that contrast because it has a defined carbon and nitrogen source that many Aspergillus species metabolize in distinct ways, producing characteristic colony colors and textures. For instance, some species form dark pigmented colonies, others yield yellow-green or blue-green hues, and growth rate can also vary by species on this medium. Those consistent color and growth differences make it easier to distinguish among Aspergillus species on sight.

Other media serve different purposes. Dermatophyte Test Medium is designed mainly to identify dermatophytes from skin samples, not to differentiate Aspergillus species. Corn Meal Agar emphasizes microscopic features and sporulation patterns rather than broad pigmentation differences for species-level ID. SABHI (Sabouraud-based) media are general fungal isolation media and aren’t tailored for differential identification of Aspergillus species.