At least I’m pretty sure (“Battus philenor”). The other possibility would be Spicebush Swallowtail (“Papilio troilus”), but the Spicebush Swallowtail has two rows of orange spots under its hind wings while the Pipevine Swallowtail has a single sub-marginal row.
I note that 1/400-th of a second is not fast enough to “freeze” the motion of its proboscis…
Retired economics professor (“dismal scientist”). Married 40+ years to the love of my life; we have two grown daughters, both married, two granddaughters and a...