Rhizopus delemar is the proper name for Rhizopus oryzae fumaric-malic acid producers.

The zygomycete Rhizopus oryzae currently is identified by sporangiophore morphology and growth temperature, but heterogeneity of the species has been reported. We examined the suitability of organic acid production as an effective taxonomic character for reclassification of the species. Strains were divided into two groups, LA (lactic acid producer) and FMA (fumaric-malic acid producers) according to organic acid production. These grouping were confirmed as phylogenetically distinct because analyses of rDNA ITS, lactate dehydrogenase B, actin, translation elongation factor-1alpha and genomewide AFLP resolved the same two exclusive clusters, corresponding with the organic acid grouping. Reclassification of strains in the FMA group as R. delemar was proposed.