It's not the best, but there's a photo of the butterfly in Figure 1(B) on page 20.

On a separate note, if you're looking for something more explicit, there are some suggestive violin plots in item F in the same figure, ironically with the caption even saying "Nymphalidae" (here referring to the family of butterflies, but "nymph" is also a general anatomical term/prefix for female genitals, or particularly the inner labia or clitoris).