Rheumaptera undulata
The Scallop Shell (Rheumaptera undulata or Hydria undulata) is a moth of the Geometridae family. It is found in most of the Palearctic ecozone and North America.
The wingspan is 25–30 mm.
The ground colour of the forewings is pale.The cross-lines are darker, wavy, evenly spaced and numerous. The outer margin is pale brown with a scalloped fringe. The hindwings resemble the forewings but are paler.