Squash Vine Borer Moth (Melittia cucurbitae)
Native to North America. The moth is often mistaken for a bee or wasp because of its movements, and the bright orange hindleg scales. The females typically lay their eggs at the base of leaf stalks, and the caterpillars develop and feed inside the stalk, eventually killing the leaf. They soon migrate to the main stem, and with enough feeding damage to the stem, the entire plant may die. For this reason, it is considered a pest that attacks cultivated varieties of squash.
This adult was taking food from milweed (Asclepia syriaca) flowers