“…Several morphological and electrophysiological studies have been carried out in different Apoidea species, describing the antennae sensillar patterns in both males and females (Gupta, 1992;Wcislo, 1995;Ågren and Hallberg, 1996). In Apis mellifera L. several morphological studies have focused on the antennal sensilla of the different colony members (Richards, 1952;Slifer and Sekhon, 1961;Dietz and Humphreys, 1971), leading to mapping of the different number and type of sensilla in the three forms (Chauvin, 1968): the workers have about 6500 sensilla per antenna (Esslen and Kaissling, 1976), the queen, 2-3000 (Dade, 1962) while the drones have the highest number, about 20 000. This enormous difference among castes and sexes is mostly due to sensilla placodea which make up about 18 600 in drones (Brockmann and Brückner, 2001).…”