Small moth, about half an inch long. Pure white wings save for a yellow border at the leading edge. Top of head yellow to match the yellow border. Body also yellowish with large black spots on abdomen. Flies from late spring to fall in open areas where milkweeds and dogbanes are found. Usually flies at night, but sometimes in the day. Is one of those moths that can jam bat echolocation with continuous clicking noises.

The caterpillar is a short bit of gray to yellow to white fuzz. Feeds on foliage of milkweeds and dogbane.

Native to pretty much the entire lower 48 and southern Canada. Favors open areas where milkweeds and dogbane plants are found, which includes all the open areas of the Park.

Two other species in the genus are very similar but differ in the details of their yellow borders. Neither has been seen in the Park.