Gulf fritillary may be mating

This is right beside the San Antonio River. I found it interesting because I believe there is a little butterfly head in front of it, making me think they may be mating. Also, this is the first photo I've taken with what looks like golden/shiny vertical lines on the wings that may be the place pheromones are transmitted as mentioned in the species literature. You must zoom in on the photo to see these lines better.

. Further research has confirmed that the glitter-like lines are only on males, and males have a longer abdomen than females. The photo above is a male.