Mayflies (Ephemeroptera)

Greek "ephemera" (short-lived) + "ptera" (wings)
Mayflies have two pair of wings held upright over the back: large fore wings and much smaller hind wings. They have three filiments at the end of the abdomen that look like tails. They are found near water, and the larva and nymph of mayflies live in water. Mayflies are a good indicator of whether a stream is unpolluted since they only live in fresh, unpolluted water. Most mayflies have a very short lifespan - some species emerge, reproduce, and die in a single day. Adult mayflies do not have mouthparts and they do not eat. Nymphs and larvae eat water plants and algae.


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© 2004 Joyce Gross
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© 2006 Joyce Gross
click for enlargement
© 2004 Joyce Gross

Quick ID

  • Triangular front wings held up straight
  • Much smaller hind wings
  • 2-3 long threads at end of abdomen
  • Long front legs, held out in front

More information about Mayflies

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Last updated: Jan 2, 2017