This beauty is a Great Mormon, part of the Swallowtail family. It is a large butterfly with a 120 to 150 millimetre (4.7 to 5.9 in) wingspan. It has four male and 26 female forms, many of them being mimics of unpalatable butterflies. This one is a female “alcanor” form. Isn’t she gorgeous?
I've never seen one like this before!