Flagellar sensilla in male and female European beewolves, <i>Philanthus triangulum</i> F. (Hymenoptera: Sphecidae)

We investigated the morphology of the antennal sensilla of a sphecid wasp, the European beewolf Philanthus triangulum, to provide an inventory for the species and to compare the sensillar equipment between the sexes. The density of sensilla increased from the base to the tip of the antennae. We distinguished nine different types of sensilla. One type has not yet been described in Hymenoptera. The large sensilla basiconica occurred only on the antennae of female beewolves. We discuss the functional significance of the difference between the sexes and compare our results with data from other sphecids and the honeybee Apis mellifera.