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Sticker of Common pill bug
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Common pill bug

Armadillidium vulgare
Eats: Leftovers and dead thingsWoodliceGardens and meadows14 legsNot an insect, but a bug cousin

The common pill bug is a little grey armoured creature that rolls into a perfect ball when you touch it. It is not an insect at all but a cousin of crabs and shrimps that lives on land. It loves dark, damp places under stones and wood.

Fun fact: woodlice are not insects. They are crustaceans, cousins of crabs and shrimps, that live on land.
Lives in
Started around the Mediterranean, now in gardens and woods almost all over the world
Length
0.8 to 1.8 cm (0.33 to 0.71 in)
Top speed
about 0.18 km/h (0.11 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. It cannot bite or sting. Put it back gently in a damp place after you look at it.
What does it eat?
It mainly eats dead, rotting leaves and plants. It also nibbles seeds, fungi, dung and dead animals, which helps keep the ground clean.
For real!Photo of Common pill bug
Picture by Xeroporcellio. CC BY 4.0, via Wikimedia Commons.

How big is it?

How long is it?

Common pill bug about 1.8 cm long (0.71 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 3 grains of rice in a rowit has about 14 legscould run across a dinner table in 20 seconds

How big is Common pill bug compared to YOU?

Just maths in your browser. Nothing is saved or sent anywhere.

How fast is it?

cool stuff

Fun facts

1

When it rolls up, it makes a perfect ball with no gap at all.

2

It must not dry out, so it hides in the daytime and comes out to eat at night.

3

It sees poorly and feels its way with its bristly antennae.

4

The mother carries her eggs in a little pouch under her belly until the babies hatch.

5

People keep them as pets because they come in many colours.

you asked

Most asked questions about Common pill bug

?Is a pill bug an insect?

No. It is a crustacean, a land-living cousin of crabs and shrimps. It has 14 legs, not 6.

?What do pill bugs eat?

Mostly dead leaves and rotting plants, which helps turn them back into soil.

?Why do pill bugs roll into a ball?

To protect themselves from enemies and to keep from drying out.

Myth buster

Myth: A pill bug is an insect.

Truth: No. It is a crustacean, a cousin of crabs and shrimps, and it has 14 legs instead of an insect's 6.

For bug experts

Scientific name
Armadillidium vulgare
Group
Woodlice
Family
Armadillidiidae
Classification
Malacostraca > Isopoda > Armadillidiidae
Lives on
Europe, Asia, Africa, North America, South America, Australia and Oceania
Also known as
Roly-poly, Potato bug, Slater, Doodle bug

Where the facts come from

  1. Armadillidium vulgare (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 Xeroporcellio. CC BY 4.0, 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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