关键词: 瓢虫科, 黄斑盘瓢虫;一雌多雄, 交配选择, 繁殖能力, 后代适应性

Abstract: 【Aim】Although polyandry is common among Coccinellidae, the data attained in various studies are insufficient to explain the general adaptive significance (or fitness consequences) of female remating and polyandry. Temperature was used as a stressor in the study. This study aims to evaluate whether certain benefits of polyandry in terms of increased fitness are also passed on to the progeny. 【Methods】The present study examined the fitness consequences of three mating treatments in Coelophora saucia (Mulsant) (Coleoptera: Coccinellidae): monandry (five matings with same male; one mating/day), sequential polyandry (five matings with five different males with one mating/day with a new male), and simultaneous polyandry (five matings with five males introduced together allowing female to select male to mate; one mating/day). Changes in fecundity and egg fertility, and offspring development and survival of the different mating treatments under different temperatures (25, 27 and 30℃) were observed. 【Results】The results revealed that females subjected to simultaneous polyandry and thus allowed mate choice or competition amongst males had maximum reproductive performance and offspring best suited to developing and surviving at a wider temperature range. However, sequential polyandrous females had similar reproductive performance as the monandrous female. 【Conclusion】This indicates that in the absence of mate choice or male competition conditions, benefits of polyandry are not evident. This could be either due to sperm competition amongst subsequent male ejaculates or female cryptic choice. The lack of benefits of polyandry in absence of mate choice as observed in this study has not been previously observed in insects to the best of our knowledge.

Key words:  Coccinellidae, Coelophora saucia, polyandry, mate choice, reproductive performance, offspring fitness