mothguide.com Erannis defoliaria
Rather similar in wing pattern to Erannis defoliaria, especially to the vancouverensis subspecies, which is more boldly patterned.
However, defoliaria currently only occurs in Iceland and Eurasia. E. tiliaria does not occur in either of these places.
Distribution pattern: Introduced in Iceland (Wolff 1971), native to Eurasia.