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Sticker of Dark Hendrickson
Bug card No. 1276 of 4,939

Dark Hendrickson

Ephemerella subvaria
Eats: Nothing as a grown-upOther insectsPonds, rivers and shores6 legs

The dark Hendrickson is a mayfly from North America. It spends most of its life as a young one at the gravelly bottom of cool, fast streams. In spring the grown-ups fly up out of the water with just one job: to find a mate.

Lives in
Eastern and central North America, in the United States and Canada, in cool, clean streams
Top speed
about 5 km/h (3.1 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless. Mayflies cannot bite or sting.
What does it eat?
The grown-ups do not eat at all. Their young munch rotting plants and algae on the stream bottom.
For real!Photo of Dark Hendrickson
Picture by Bob Henricks. CC BY-SA 2.0, via Wikimedia Commons.

How fast is it?

cool stuff

Fun facts

1

It only lives in very clean water, so finding it tells you a stream is healthy.

2

The males have big reddish eyes and a rusty red body, which is why it is also called the red quill.

3

The females are bigger than the males and duller, grey-brown to olive.

4

Just before it is fully grown, it can already fly and has three long tails.

5

The grown-ups come out in April and early May, after the first warm days of spring.

you asked

Most asked questions about Dark Hendrickson

?Does the dark Hendrickson bite?

No. Mayflies cannot bite or sting, and the grown-ups do not even eat.

?Why is the dark Hendrickson important?

It only lives in clean water, so it shows that a stream is healthy. It is also food for trout.

For bug experts

Scientific name
Ephemerella subvaria
Group
Other insects
Family
Ephemerellidae
Classification
Insecta > Ephemeroptera > Ephemerellidae
Lives on
North America
Also known as
Hendrickson mayfly, Red quill, Red quill spinner, Whirling dun

Where the facts come from

  1. Ephemerella subvaria (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 Bob Henricks. CC BY-SA 2.0, Wikimedia Commons. The sticker of this bug is drawn from this picture.

If we got something wrong, sorry, we are bug fans, not a science journal. Tell us at [email protected] and we will fix it.

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More from the same group: Other insects

Also at home here: Ponds, rivers and shores

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