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Sticker of Yellow fly of the Dismal Swamp
Bug card No. 4863 of 4,939

Yellow fly of the Dismal Swamp

Diachlorus ferrugatus
Eats: BloodFlies and mosquitoesPonds, rivers and shores6 legs

The yellow fly of the Dismal Swamp is a yellow horse fly with blue-green eyes striped with purple. It flies almost silently, so people often notice it only when it bites. It lives near water and woods in warm places.

Lives in
From the southeastern USA, from New Jersey to Texas, down to Costa Rica, near water
Length
1 cm (0.39 in)
Top speed
about 19 km/h (12 mph)
Flying, estimate
Can it hurt you?
Can bite
The female gives painful bites that leave itchy bumps. Long sleeves, a hat and insect spray help, and a grown-up can help if a bite itches a lot.
What does it eat?
The female drinks blood, which she needs to make her eggs.
For real!Photo of Yellow fly of the Dismal Swamp
Picture by Judy Gallagher. CC BY 2.0, via Wikimedia Commons.

How big is it?

How long is it?

Yellow fly of the Dismal Swamp about 1 cm long (0.39 in)A grain of rice about 6 mm (0.24 in)A toy building brick about 3.2 cm (1.3 in)
small enough to sit on your fingernailas long as 1.5 grains of rice in a rowcould fly across a whole football pitch in 20 secondsmoves 530 times its own body length every second

How big is Yellow fly of the Dismal Swamp compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

It has been called the most aggressive fly in Florida.

2

It likes to hide in Spanish moss hanging from trees.

3

It bites most in summer and early autumn, in the late afternoon and on cloudy days.

4

In Belize people call it the doctor fly.

5

Its larvae are thin white grubs covered in fine yellow fuzz.

you asked

Most asked questions about Yellow fly of the Dismal Swamp

?Do yellow flies bite?

Yes. The females bite people to get blood, and the bites hurt and itch.

?How can you keep yellow flies away?

Insect spray helps, but when there are many of them, long sleeves, gloves and a head net work best.

For bug experts

Scientific name
Diachlorus ferrugatus
Named by
Fabricius, 1805
Group
Flies and mosquitoes
Family
Tabanidae
Classification
Insecta > Diptera > Tabanidae
Lives on
North America
Also known as
Yellow fly, Doctor fly

Where the facts come from

  1. Diachlorus ferrugatus (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 Judy Gallagher. CC BY 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: Flies and mosquitoes

Also at home here: Ponds, rivers and shores

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