A Synoptic Key and Evaluation of Species in the Aspergillus Flavus Group

SUMMARY

A synoptic key for identification of 16 taxa in the Aspergillus flavus group is presented. The key uses definitive and readily observable features: vesicle size, color of conidial heads, conidiophore and conidium features, growth at 37 C, and form and size of sclerotia. Brief descriptions are included as an aid to identification. The author's interpretation of relatedness among species, based upon morphological and cultural data and involving an ordination using coefficients of similarity, is compared to results from chemotaxonomic studies by other workers. A distributional and ecological analysis has been based upon examination of species lists in nearly 100 surveys. Aspergillus leporis, A. avenaceus, A. sojae, A. subolivaceus, and A. zonatus, in particular, are interpreted as morphologically and ecologically distinct species. Aspergillus flavus, A. oryzae, and A. parasiticus are in part domesticated species with broad and overlapping morphologies. Aspergillus toxicarius appears to be a biseriate form of A. parasiticus, and A. kambarensis probably belongs with A. oryzae.