In coccidioidomycosis, containing many endospores form in the lungs.

spherules

Explanation:

Like histoplasmosis, coccidioidomycosis is acquired by the inhaling fungal spores.

Arthrospores are formed by the hyphal fragmentation in this case. Once in body, fungus differentiates into the spherules which are filled with the endospores.

Most of the C. immitis infections are self-limiting and asymptomati. The endospores are transported in blood, disseminating infection and thus leading to formation of granulomatous lesions on face and nose. I

Thus, spherule is a thick-walled spherical structure which encloses the endospores and occurring in parasitic form of the fungi of genus Coccidioides.