
Appearance
The wingspan is 27–40 mm. Adult seasonally and sexually dimorphic, but the middle of the outer margin of the hindwing and forewing are conspicuously pointed in all forms, and there is usually a dark triangular patch along the costa near the apex of the forewing .The spring brood of both sexes has mottled light brown wings. The summer brood male is bright yellow with reddish-brown shading, while the female is all yellow. Adults are on wing from April to May with an occasional mid March and mid June record as well as from July to August with occasional September to mid October records. There is one generation in Canada, and at least two southward.

Food
The larvae have been recorded on Aceraceae, Anacardiaceae, Betulaceae, Ebenaceae and Rosaceae species, including ''Alnus rugosa'', ''Physocarpus opulifolius'' and ''Prunus serotina''.References:
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