The left hindwing is slightly damaged as you can see in these photos. There are a number of possible causes for that, including insufficient nutrition as a larva, rapid temperature fluctuations during adult development, or simply an obstruction when emerging from the chrysalis or while pumping and drying the wings.
|Dorsal view of male giant swallowtail|
|Ventral view of male giant swallowtail|
|Giant swallowtail and chrysalis|