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A medium-small size (approx. 2.5 cm wingspan) broad-winged grey and black moth. The forewings are pale grey, crossed by a series of dark bands. A small dark patch at the wing base is followed by a prominent slightly curved dark complete antemedian line. The postmedian line is made up of three parallel dark lines, separated by thin lines of light scales; prominent on the upper third or half of the wing, becoming faint or obsolete across the lower half. The outer edge of the upper third of the band is notched inward. The outer edge of the forewing is broadly darker grey, especially on the upper half of the wing. The hindwings are pale grey or dirty white, crossed by a series of faint bands and darkening toward the outer margin. All four wings have a small black discal dot. Sexes alike except male antennae bipectinate or bifasiculate; female simple. The small size, dark antemedian band and dark, notched upper third of the postmedian band combined with the lack of prominent brown or rusty scaling will separate abrasaria from most other small Alberta geometrids.

Adults are mainly nocturnal and come to light. There are no records for the larval hostplant(s) in NA; in Europe abrasaria is reported to use several species of bedstraw (Gallium). Adults are present in Alberta from mid-June through mid August, with the main flight in July. It is possible there is a small second brood in mid August. The larva of the nominate subspecies is illustrated in color on the web.

NL and LB west across the wooded parts of Canada to BC. In Alberta Most common in the Aspen parklands, southern Boreal forest and lower foothills regions; also present in the mountains south of the Crowsnest Pass and in the Boreal forest region. Open woodland and edges; meadows.