Like most other moths, it is nocturnal but is sometimes observed at lights. The imposing larva, known as the hickory horned devil, is most often observed when it is full grown and comes down from the trees to wander in search of a site for pupation. The regal moth is found throughout the deciduous forest areas of the eastern U.S. from Missouri to Massachusetts and southward to Texas and central Florida. It is more common in the southern part of its distribution. The regal moth has a wingspan of 9.5-15.5 cm.
Females are larger than males.
The forewings are gray to gray-green with orange veins and a row of seven to nine yellow spots near the distal margin. There also are single yellow discal and basal spots. The hind wing may also have one to two rows of gray-green spots. The body is orange with narrow yellow banding. They vary slightly in color, but are commonly blue-green.