Photo © Ilia Ustyantsev
Spargania luctuata, the white-banded carpet, is a moth of the family Geometridae. The species was first described by Michael Denis and Ignaz Schiffermüller in 1775. It is found throughout northern and central Europe, North Asia and North America.
The wingspan is 30–34 mm. The length of the forewings is 14–15 mm. The moth flies in two generations from the end of April to September.
The caterpillars feed on various species of rosebay willowherb.
Source: Wikipedia
The primary larval foodplant is Rosebay Willowherb (Chamaenerion angustifolium).