Mayfly

Aquatic insects of the order Ephemeroptera

Mayflies (also up-winged flies or up-wing flies, or drake-flies in the UK; shadflies or fishflies in northern U.S. and Canada) are aquatic insects belonging to the order Ephemeroptera. This order is part of an ancient group of insects termed the Palaeoptera, which also contains dragonflies and damselflies. Over 3,000 species of mayfly are known worldwide, grouped into over 400 genera in 42 families.

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