Smerinthus jamaicensis (Dru.)
Courtesy Janice Stiefel
Identification: Covell, Moths of Eastern North America, Page 37 -- Usually distinguished by the two small blue spots on the hindwing. A black bar divides the blue spot in half. A third blue spot is present toward the base of the hindwing of some specimens. A more reliable characteristic is the nearly straight costal margin of the hindwing and no terminal claw on the foretibia. The caterpillar host plants are apple, ash, birch, elm, and willow.