About 64% of species in genus Aspergillus lack knowned sexual reproduction in their life cycle,[2] causing them were classfied into Fungi imperfecti before, producing the teleomorph name Neosartorya fischeri when the sexual reproduction were discoverd.

But after the abolish of the Fungi imperfecti nomenclature, Aspergillus which is the anamorph name of should be the holomorph name when we discuss this species.

According to the number of mating type produced by individual, fungi thus to classfied into homothallic and heterothallic.

And Aspergillus fischeri is homothallic, which can producing both mating type within one individuals.

Recent research [4] has show that the difference between these two species, such as the progression when treating on immune depress rat.