Sthenopis purpurascens, the four-spotted ghost moth, is a species of moth of the family Hepialidae. It was described by Packard in 1863. It is found in Canada and the United States, from Labrodor and New York north and west to British Columbia and the Northwest Territories, south in the mountains to Arizona. The larvae feed on Populus, Salix and Alnus species. They bore into the roots of their host plant. The larvae have a cream-white body and brown head and reach a length of 50–60 cm. They need two years to complete their lifecycle