Comprehensive DescriptionRead full entry
General DescriptionA very large (8.5-11.0 cm wingspan) narrow-winged heavy-bodied moth. The forewings are very dark grey or dull black. The leading edge, particularly the basal two-thirds, is sharply contrasting white or pale grey. The hindwings are black, crossed by a white median band and with a pale grey base and outer margin. The abdomen has a series of large black and white lateral spots. The dark blackish forewings with the contrasting pale leading edge will separate it from all other Alberta sphinx. The similar S. vashti and S. chersis are much paler grey. See also the female of S. luscitiosa.