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Sticker of Least pygmy woodlouse
Bug card No. 2562 of 4,939

Least pygmy woodlouse

Trichoniscus pygmaeus
Eats: Leftovers and dead thingsWoodliceGardens and meadows14 legsNot an insect, but a bug cousin

The least pygmy woodlouse is a teeny tiny woodlouse, smaller than a grain of rice. Its shell is pinkish or yellowish and a little see-through. Down the middle of its back runs a thin coloured line.

Fun fact: woodlice are not insects. They are crustaceans, cousins of crabs and shrimps, that live on land.
Lives in
Britain and Ireland, and a small area of the USA
Length
2.5 mm (0.1 in)
Top speed
about 0.07 km/h (0.04 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. It cannot bite or sting people.
What does it eat?
Like other woodlice, it nibbles on dead leaves and other rotting plant bits in the soil.
For real!Photo of Least pygmy woodlouse
Picture by Lark999. CC BY 4.0, via Wikimedia Commons.

How big is it?

How long is it?

Least pygmy woodlouse about 2.5 mm long (0.1 in)A grain of rice about 6 mm (0.24 in)
2.5 of them in a row are as long as one grain of riceit has about 14 legscould run across a dinner table in 51 seconds

How big is Least pygmy woodlouse compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

It is only about 2.5 millimetres long, so you could fit several on your fingernail.

2

Its shell is partly see-through, pinkish to yellowish in colour.

3

A yellow or pinkish line runs down the middle of its back.

4

Woodlice are not insects. They are crustaceans, cousins of crabs and shrimps, and have 14 legs.

you asked

Most asked questions about Least pygmy woodlouse

?How big is the least pygmy woodlouse?

Very small, only about 2.5 millimetres long.

?Is a woodlouse an insect?

No. Woodlice are crustaceans, related to crabs, and they have 14 legs instead of 6.

For bug experts

Scientific name
Trichoniscus pygmaeus
Group
Woodlice
Family
Trichoniscidae
Classification
Malacostraca > Isopoda > Trichoniscidae
Lives on
Europe, North America

Where the facts come from

  1. Trichoniscus pygmaeus (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 Lark999. CC BY 4.0, 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: Woodlice

Also at home here: Gardens and meadows

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