Mycetomas are caused by various species of fungi and bacteria, which occur as saprophytes in soil or on the plants. Actinomycotic mycetoma is caused by aerobic species of actinomycetes belonging to the genera Nocardia, Streptomyces and Actinomadura with Nocardia brasiliensis, Actinomadura madurae, Actinomadura pelletieri, and Streptomyces somaliensis being most common.