Mayflies. Order Ephemeroptera. Only insects that moult after they have wings. Aquatic as larvae, gills along the side of the abdomen. Larvae take up to a year to develop, and then moult to a winged stage called the subimago before reaching adulthood - at which point they die very quickly.
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Nemoptera is a Palearctic genus of insects of the family Nemopteridae or spoonwings. All species are diurnal with an exclusively floral diet, preferring to fly in open spaces in full sunshine while visiting flowers. They can be recognized by their very long hind wing prolongations. By Jo Williams