Helminthosporium species

A rapidly-growing fungus that produces a dark gray to black colony with a black reverse, within five days, when incubated at 25oC (77oF). The hyphae, conidiophores, and conidia are pigmented olivaceous-brown (dematiaceous). It is found worldwide and is very common. It can be isolated from the air, plants, and soil. Rarely, it can be an opportunistic human pathogen causing eye (corneal ulcers) infections and subcutaneous or systemic disease.