Acentria ephemerella – Water Veneer

Family Crambidae   Hodges # 5299

Caterpillar foods:  Eurasian Watermilfoil, pondweeds (Potomogeton spp.)  and Canadian Waterweed (Elodea canadensis)  (Bugguide)

This species is native to Eurasia, and was introduced to North America in the 1920s.  There have been attempts to use it to control Eurasian Watermilfoil, so far without success.  Its larvae are aquatic; they overwinter underwater, attached to leaves of their food plants.  Adult females are wingless;  adult males have wings.  (Bugguide)

There’s a note by Dr. Jean Francois Landry of the Canadian National Collection of Insects, Ottawa, Canada, on one of the Bugguide pages.  He says:  “This is Acentria ephemerella, family Crambidae, subfamily Acentropinae. This is a very cool and unsual moth. It is widespread here and in Europe. Its larvae are subaquatic and feed on aquatic plants, mainly Canadian waterweed (Eleodea canadensis) and pondweed (Potamogeton) up to a depth of 2m in standing or slow-moving water. Females come in two forms, one fully winged, the other with rudimentary wings and flightless. Wingless females swin below the water surface. Mating takes place on the water surface. Winged adults swarm at night, in June in our area. Adults live only a couple of days and winged ones can fly a great distance from the water. ”




on Bugguide