male genitalia typically exhibit patterns of rapid and divergent evolution, and there is now considerable evidence that sexual selection is an important driver of these patterns of phenotypic variation. Female genitalia have been less well studied, and are generally thought to be relatively invariant. Here we use experimental evolution to show that sexual selection drives the correlated evolution of female and male genital morphology in the scarabaeine dung beetle Onthophagus taurus. moreover, we use quantitative genetic analyses to provide a rare insight into the genetic architecture underlying morphological variation in female genital morphology, and uncover evidence of the genetic covariation with male genital morphology that is expected to arise under persistent sexual selection.