Euthrix potatoria, the drinker, is an orange-brown moth of the family Lasiocampidae. It is found in Europe. The moth's wingspan is 45–65 mm and is identifiable by two white spots on the forewings. It flies from June to August depending on the location. The larvae feed on various grasses and reeds. The species' common and scientific names derive from the larva's supposed drinking of drops of dew.