Eudonia lacustrata is a species of moth of the family Crambidae. It is found in Europe, north-West Africa, Asia from Turkey, Iran and Syria to Siberia and the western part of China (Hunan). The subspecies E. lacustrata persica is found in Iran and Armenia. The wingspan is 16–18 mm. The moth flies from May to August depending on the location. The larvae feed on various mosses.