Northern Prairie Wildlife Research Center
Wingspan 3.3 cm. Forewing is slightly falcate, lightly speckled brown with a dark brown median band and postmedian line, or separate small postmedian spots. This geometrid is abundant in wet conifer forests in the Pacific West. Moths fly in the early spring. Caterpillars feed on the fronds of ferns, particularly sword fern (Polystichum munitum).