[2] Colonies of Madurella grisea are slow growing, dark, leathery, and folded with radial grooves and with a light brown to greyish surface mycelium.

With age, colonies become dark- to reddish-brown and acquire a brownish-black reverse.

Grains of Madurella grisea (tissue microcolonies) are black, round to lobed, soft to firm, up to 1.0 mm, with two distinctive zones, a hyaline to weakly pigmented central zone and a deeply pigmented periphery.

M. grisea can be distinguished from Madurella mycetomatis by the inability to grow at 37C or assimilate lactose.

Antifungal susceptibility testing of individual strains is recommended.