University of Alberta Museums Search

A medium-size (3.0 - 3.2 cm wingspan) grey moth with paler grey and black markings. The forewing has a prominent long narrow black basal dash that meets the pale, elongate claviform, the later faintly outlined in black. The pale orbicular and reniform are combined into a long, narrow wedge, also outlined in black. The normal cross lines are reduced to a series of dark spots on the costa. The veins on the outer half of the wing are finely marked in black scales. The subterminal line is indicated by a series of pale streaks, and the fringe is checkered grey and white. The hindwings are dirty white on the basal half, darkening to form a wide grey terminal band. There is also a small, grey discal bar. The hindwing fringe is grey on the basal half then white. Antennae are simple, and the sexes are similar. Most likely to be confused with O. riparia.