Aflavarin 131, a new bicoumarin, and f3-aflatrem 1111, an isomer ofthe tremorgen aflatrem, were isolated from the sclerotia ofAspergillusfbvuJ. The structures were determined through a series of 1D and 2D nmr experiments, assisted by spectral comparisons with known compounds. Aflavarin exhibits potent antifeedant activity against the fungivorous beetle Curpophilus hemiptenrs. f3-Aflatrem causes a significant reduction in the growth rate of the corn earworm Helicoverpa ZM. The presence of nominine 1131 as a minor metabolite ofA. fbvus is reported for the first time.