Aspergillus cumulatus sp. nov., from rice straw and air for meju fermentation.

A new species named Aspergillus cumulatus sp. nov. is described in Aspergillus section Aspergillus (Eurotium state). The type strain (KACC 47316(T)) of this species was isolated from rice straw used in meju fermentations in Korea, and other strains were isolated from the air in a meju fermentation room. The species is characterized by growth at a wide range of water activities and the formation of aerial hyphae on malt extract 60% sucrose agar (ME60S) that resemble a cumulus cloud. Furthermore, A. cumulatus produces yellow ascomata containing small lenticular ascospores (5.1-5.7 μm) with a wide furrow, low equatorial crests, and tuberculate convex surface. The species is phylogenetically distinct from the other reported Aspergillus section Aspergillus species based on multilocus sequence typing using rDNA-ITS, β-tubulin, calmodulin, and RNA polymerase II genes.