Heterospecific physical interference modulates the reproductive attributes of a ladybird beetle

AbstractPropylea dissectaandCheilomenes sexmaculata(Coleoptera: Coccinellidae), are similar sized, co-ocurring aphidophagous insects that share common resources. We conducted the current study to observe the phenomenon of reproductive interference and effect of presence of heterospecific adults (C. sexmaculata) on the reproductive output ofP. dissecta. For this, we used two reciprocal mating combinations of heterospecifics. The first heterospecific combination usedP. dissectamales withC. sexmaculatafemales and the second heterospecific mating combination usedP. dissectafemales withC. sexmaculatamales. To further examine the effect ofC. sexmaculatamale onP. dissectafemale, we used mixed mating treatments (C. sexmaculatamale with conspecific pair ofP. dissecta). Our results suggested that (1) in the first heterospecific mating combination, mating did not commence betweenP. dissectamaleC. sexmaculatafemale, while in the second heterospecific mating combination, mating was recorded betweenP. dissectafemale andC. sexmaculatamale, (2)C. sexmaculatamale interferes the conspecific mating inP. dissectathrough multiple mating attempts which resulted in reduced fitness and reproductive success ofP. dissecta. Overall, we illustrated the negative effects of reproductive interference caused byC. sexmaculataon the reproductive output (fecundity and egg viability) ofP. dissecta.