One of the largest butterflies in North America, the Giant Swallowtail lives throughout Texas. You will see this butterfly in your garden and flitting along wooded paths.
The Giant Swallowtail is a strong flyer and rarely sits still for a picture. Still, good light and a high shutter speed will help you get a great shot.
I also got lucky once and came out to one who had gotten caught in the cold in my garden. He was stuck still until the sun rose high enough to warm him up. I made sure to get some closeups while I had a captive subject!