A common feature of dematiaceous molds is the production of melanin pigment, which confers dark pigmentation to hyphae. Dematiaceous molds are typically dark pigmented on the surface and reverse sides of the plate, because both their hyphae and conidia are melanized. There are some species that produce only pigmented conidia, which imparts a dark top surface and a light-colored reverse.
Bipolaris, Curvularia, and Alternaria spp. grow relatively rapidly.
Scedosporium apiospermum/boydii is a moderately rapid grower.
Scedosporium prolificans is slow growing.
Dematiaceous molds are most often involved in subcutaneous infections, although they can be isolated from a variety of specimen types from various anatomic locations.
The image to the right shows a Bipolaris spp. culture plate demonstrating dark pigmentation.
Image courtesy of the CDC.