Hemaris tityus; seen at about 14:15 on 17th May 2011 at Oldtown, Ardgay, NH 595 895, feeding on Erysimum nectar.
Weather was sunny, warm and breezy.
Tags: bee hawkmoth, day flying moth, Erysimum, Hemaris tityus, moth, Narrow-bordered Bee Hawkmoth, Scarce B
Excellent record Phil & Marion. Your garden seems to be a prime spot for these moths.