This species is quite similar to C. unijuga with its relatively light forewings and dark markings.
C. unijuga, however, lacks the dark bar paralleling the inner margin from the wing-body juncture all the way to the outer margin.
Below is an image of C. unijuga for comparison.
Larva of both species feed on poplar and willow foliage. Often where you find one, you will also find the other.
Henry (left-click on the frog) to find more