Marasmarcha lunaedactyla is a moth of the Pterophoridae family. It is found in most of Europe, except Ireland and most of the Balkan Peninsula. The wingspan is 18–22 mm. Adults have a moon-shaped creamy-white marking at the cleft of their brownish forewing. Adults are on wing from June to August. The larvae feed on the flowers and young shoots of Ononis species, including Ononis repens, Ononis spinosa, Ononis natrix and Ononis rotundifolia and Ononis arvensis. Pupation takes place along a shoot or on a leaf of the food plant.