Northern Prairie Wildlife Research Center
Wingspan 2.3 cm. Forewing is elongate and pointed with white and black costal and submarginal patches. This geometrid is very common in the Pacific West. Moths fly in early spring. Caterpillars feed on the foliage of buckthorn (Rhamnus purshiana).
Similar species: more than 120 species of Eupithecia occur in North America and are very difficult to identify. Typically genitalia must be observed for distinguishing the species. Also, adults reared from field-collected caterpillars with knowledge of host plants can be helpful for accurate identifications; among the species of Eupithecia, the forewing of E. ravocostaliata is one of the more intricately patterned and is the most common species reared from the foliage of buckthorn.