Cuticular hydrocarbons as cues of caste and sex in the German wasp Vespula germanica

Abstract

The complex system of communication used by social insects is responsible for their success on Earth. Cuticular hydrocarbons (CHCs) are considered the most commonly used form of communication among social insects. The best-known function of CHCs is to distinguish nestmates, providing cues to the whole colony to identify potential threats. In some species, CHCs function as queen pheromones, which contribute to the queens’ ability to regulate the reproductive division of labor. Additionally, differences of CHCs were described in castes and they are also important in sex recognition. Here, we reinvestigated the chemical composition on the cuticle of German wasp Vespula germanica and we found that proportions of linear alkanes were more abundant in the cuticle of queens than other castes. Chemical analysis between caste and sex, including data of virgin queens and males, showed that each group possesses different compositions on their cuticle, being mostly quantitative differences. Thus, individuals of V. germanica may recognize and discriminate caste and sex through subtle chemical variations, or alternatively, based on templates used in nestmate recognition. The chemical analysis provides correlative evidence of CHCs being used as cues in the chemical communication of this species.