Multiple behavioural asymmetries impact male mating success in the khapra beetle, Trogoderma granarium

Abstract

Extensive research has recently been conducted to shed light on mating behavioural asymmetries in various species of vertebrates. However, little is available on this key issue for invertebrates, especially for species of the order Coleoptera. In the present study, we highlighted the presence of four population-level lateralized mating traits in the mating behaviour of an alien and invasive pest of stored products, the khapra beetle, Trogoderma granarium (Dermestidae). Male recognition and mounting, as well as the female post-copulation kicks, were left-biased, while male foreleg tapping acts were right-biased. Notably, left-biased asymmetries in the recognition approach led to significant differences in recognition duration, the number of head wagging acts, whole mating duration and, most importantly, male mating success. Overall, the results reported here represent a unique example of four subsequent mating traits lateralized at the population level which influence male mating success. From an applied perspective, the quantification of lateralized mating traits is expected to contribute to a better understanding of key biological traits of this species, which can be used for the prediction of its spread and population growth parameters.