Gynnidomorpha alismana, the water plantain conch, is a moth of the family Tortricidae. It was described by Ragonot in 1883. It is found in most of Europe, except Spain, Switzerland, most of the Balkan Peninsula and Ukraine. Outside of Europe, it is found in China (Anhui, Fujian, Guangdong, Guizhou, Hebei, Heilongjiang, Hubei, Hunan, Inner Mongolia, Jiangxi, Jilin, Shaanxi, Yunnan) and Korea. It is found in riverine and other watery habitats. The wingspan is 11–14 mm. Adults are on wing from June to August.