Family Hydrometridae

Hydrometra gracilenta Horvath

On floating leaves of aquatic vegetation or on the water surface of standing and slowly flowing waters, also found at edges of drying water bodies and in wet soil and mosses along the shores; zoophage (observed to consume 19-20 mosquito larvae per night); univoltine; overwinters as imago (Kanyukova 1973). West Eurasian.

Hydrometra stagnorum (Linnaeus)

On floating leaves of aquatic plants or on wet soil and mosses along the shores of ponds or slow-moving waters; zoophage (preys on small crustaceans); possibly univoltine; overwinters as imago on the shore (Kanyukova 2006). West Palearctic.