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Sticker of True armyworm
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True armyworm

Mythimna unipuncta
Eats: Nectar and pollenMothsGardens and meadows6 legs

The true armyworm is a brownish moth that flies at night. Its caterpillars got their name because they march together in long lines from field to field, like a little army. The moths travel too: north in spring and south again in autumn.

Lives in
Most of North America, and parts of South America, Europe, Africa and Asia, in fields and grassland
Wingspan
4 cm (1.6 in)
about
Top speed
about 14 km/h (8.7 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless to people. It can damage crops, but it does not bite or sting.
What does it eat?
The moths drink flower nectar and eat ripe or rotting fruit. The caterpillars eat grasses and crops, which makes farmers unhappy.
For real!Photo of True armyworm
Picture by Luis Miguel Bugallo Sánchez ( Lmbuga Commons )( Lmbuga Galipedia ) Publicada por/ Publish by : Luis Miguel Bugallo Sánchez. CC BY-SA 3.0, via Wikimedia Commons.

How big is it?

How wide are its wings?

True armyworm wings about 4 cm tip to tip (1.6 in)A toy building brick about 3.2 cm (1.3 in)A crayon about 9 cm (3.5 in)A banana about 18 cm (7.1 in)
wings as wide as 7 grains of rice in a rowcould fly across a whole football pitch in 27 seconds

How big is True armyworm compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

It can hear very well, which helps it find a mate and escape from hungry bats.

2

A female can lay 500 to 1500 eggs in her life, up to 80 in one cluster.

3

Its eggs are covered in something sticky that glues them to leaves and helps hide them.

4

If a young caterpillar is disturbed, it lets out a silk thread and drops to the ground.

5

The caterpillar grows from 4 millimetres to about 3.5 centimetres long.

you asked

Most asked questions about True armyworm

?Why is it called an armyworm?

Because its caterpillars move together in big lines from field to field, like an army.

?What does the true armyworm eat?

The caterpillars eat grasses and crops. The moths drink nectar and eat ripe fruit.

?Is the true armyworm harmful?

Not to people, but large groups of caterpillars can damage farm crops.

For bug experts

Scientific name
Mythimna unipuncta
Named by
Haworth, 1809
Group
Moths
Family
Noctuidae
Classification
Insecta > Lepidoptera > Noctuidae
Lives on
North America, South America, Europe, Africa, Asia
Also known as
White-speck moth, Common armyworm, Rice armyworm

Where the facts come from

  1. Mythimna unipuncta (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 Luis Miguel Bugallo Sánchez ( Lmbuga Commons )( Lmbuga Galipedia ) Publicada por/ Publish by : Luis Miguel Bugallo Sánchez. 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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