Unnamed spotting

The range reference was for the Western Tiger Swallowtail; Papilio rutulus. the range for the Eastern goes west to Colorado. In the middle of the country you can have both, which can be confusing.
For more fun; there is a tiny population of Appalachian Tiger Swallowtail, Papilio appalachiensis. Their range is southern Appalachian Mountains from Pennsylvania to Georgia, westward to northeast Alabama.

This butterfly was spotted in New Jersey. Range: Western North America from British Columbia south to southern New Mexico and Baja California; east to western South Dakota and southeast Colorado. A rare stray to central Nebraska. http://www.butterfliesandmoths.org/speci...