Reproductive behaviour of predaceous ladybirds (Coleoptera: Coccinellidae): A review

Abstract

Sexual activities of predaceous ladybirds (Coleoptera: Coccinellidae) involve complex interactions. Hence, we reviewed information on pre-mating, mating and post-mating behaviour to better understand their complexities and optimize their augmentation. Mate-recognition, mate-choice and mating refusals are the highlights of ladybirds’ pre-mating behaviour. Male ladybirds court the females and this behaviour declines with aging and intense sexual activities. Generally, older males exhibit coercive mating with young females, who strongly resist this approach. Copulation is characterized by either vigorous shaking or quiescent mating. In laboratory conditions, ladybirds indulged in both monogamy and polygamy (particularly polyandry) and polyandrous females surpassed monogamous ones in fecundity and fertility. Copulatory behaviour is largely driven by age, sexual status, and food with its duration indicating success in mating and progeny production. Mating duration decreases with the advancing age of ladybirds and successive matings, however, virgin males copulate for a shorter duration than the experienced ones. There is a trade-off between male mating and longevity. Mate choice, asymmetrical sexual maturity of males and females, mating refusals, differences in body size, promiscuity, post-copulatory female mating resistance were seemingly the proximal causes of sexual selection. Females are usually choosy and select better courters that have enriched male attributes, particularly, the ones who may sire numerous viable eggs in a single mating event. Post-mating behaviour highlighted females’ disinterest in remating and males’ showing prolonged mating or mate-guarding behaviour. Food, age, polyandry and multiple mating are the key factors for increased fecundity that help optimize the augmentation of ladybirds with biocontrol potential.