Fragrance collection, storage, and accumulation by individual male orchid bees

Individually marked males of two species of Euglossa were sighted repeatedl y and over considerable periods of time (up to 44 days) at artificial fragr ance baits exposed on Barro Colorado Island (BCI), Panama. Individuals swit ched between different bait chemicals that are attractive for the respectiv e species, and no bait preferences or individual bait constancy was observe d. CC-MS analyses of 153 males of three species showed that individual hind tibiae contain highly variable quantities of a complex and species-specifi c blend of fragrance compounds, mainly terpenoids and aromatics. In all thr ee species, frequency distributions of individual quantities were strongly skewed towards individuals with small amounts, and individual amount and co mplexity were positively correlated. Tibial contents of male Euglossa imper ialis that were kept alive in a flight cage for 0, 5, 10, or 15 days showed no qualitative or quantitative change over time, suggesting that the fragr ances are very efficiently stored in the hind legs. In Euglossa cognata win g wear, an established age correlate of the species, was positively correla ted with individual fragrance quantity. Our results suggest that male euglo ssines forage continuously for a variety of volatiles, store them, and fina lly acquire large quantities of a complex and specific fragrance bouquet. B oth qualitative and quantitative aspects of individual contents are likely to contain information on male phenotypic and genotypic quality.