Nigrospora sphaerica is an airborne filamentous fungus in the phylumAscomycota. It is found in soil, air, and plants as a leaf pathogen. It can occur as an endophyte where it produces antiviral and antifungal secondary metabolites. Sporulation of N. sphaerica causes its initial white coloured colonies to rapidly turn black.N. sphaerica is often confused with the closely related species N. oryzae due to their morphological similarities.
Often the common response to N. sphaerica in humans is hay fever or asthma. N. sphaerica is not widely considered a true human pathogen, however there are various reported cases of Nigrospora species in human eye and skin infections. Of those, there have only been a handful of reported cases of N. sphaerica infection in human.