Female and male genital surface microstructures in shining leaf beetles (Coleoptera, Chrysomelidae, Criocerinae)

Female genital diversity and co-evolution of female and male genitalia have been increasingly unveiled, particularly through recent studies. These findings highlight the importance of genital coupling in genital studies. In this pilot study, I examined membranous elements of female and male genitalia that come into physical contact during copulation in five representative species of shining leaf beetles by employing stereomicroscopy and scanning electron microscopy. The female genital surfaces are largely smooth, but a thickened sensilla-bearing patch is present. In contrast, the male surfaces are at least partially covered with microprotrusions. I present distribution maps of these microstructures for all study species. By comparing the results with those of previous studies, I discuss their possible functions and future research directions in this field.