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Sticker of Giant mayfly
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Giant mayfly

Hexagenia limbata
Eats: Nothing as a grown-upOther insectsPonds, rivers and shores6 legs

The giant mayfly is a pale yellow insect with see-through wings and two long tails. It spends most of its life underwater as a baby, digging in the mud. Then it flies out for only a few days to find a mate.

Lives in
North America, near lakes and slow rivers with muddy bottoms
Length
2.7 cm (1.1 in)
Top speed
about 7.5 km/h (4.7 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless. It cannot bite or sting, and it cannot even eat.
What does it eat?
The grown-ups cannot eat at all, because they have no working mouth. The babies underwater eat tiny bits of dead stuff that the water brings into their burrow.
For real!Photo of Giant mayfly
Picture by Cody Hough. CC BY-SA 3.0, via Wikimedia Commons.

How big is it?

How long is it?

Giant mayfly about 2.7 cm long (1.1 in)A grain of rice about 6 mm (0.24 in)A toy building brick about 3.2 cm (1.3 in)A crayon about 9 cm (3.5 in)
as long as 4 grains of rice in a rowcould fly across a whole football pitch in 50 secondsmoves 77 times its own body length every second

How big is Giant mayfly compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

When thousands hatch at once, the swarm can be so big that it shows up on weather radar.

2

Around the Great Lakes people call them fish flies, because the piles of mayflies make the shore smell like rotten fish.

3

The baby lives in a U-shaped tunnel in the mud and waves its feathery gills to pull fresh water through.

4

It changes its skin up to thirty times while it grows.

5

After it flies out of the water it changes its skin one more time, which almost no other insect does.

you asked

Most asked questions about Giant mayfly

?How long does a giant mayfly live?

As a flying grown-up only a few days. As a baby underwater it can live up to two years.

?Do giant mayflies bite?

No. Grown-up mayflies cannot even eat, so they cannot bite you.

?Why are there so many mayflies at once?

They all hatch at about the same time, which helps them find a mate.

For bug experts

Scientific name
Hexagenia limbata
Group
Other insects
Family
Ephemeridae
Classification
Insecta > Ephemeroptera > Ephemeridae
Lives on
North America
Also known as
Golden mayfly, Big Michigan mayfly, Great leadwing drake, Fish fly

Where the facts come from

  1. Hexagenia limbata (Wikipedia, CC BY-SA 4.0): what it looks like, where it lives, what it eats, sizes and fun facts, retold in simple words.
  2. Picture by Cody Hough. CC BY-SA 3.0, Wikimedia Commons. The round sticker of this bug is cut from the same picture.

If we got something wrong, sorry, we are bug fans, not a science journal. Tell us at hello@bugwiki.app and we will fix it.

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