Bug Wiki
Bug Wiki / All bugs / Snails, slugs and worms
Sticker of Chestnut slug
Bug card No. 0867 of 4,939

Chestnut slug

Deroceras invadens
Eats: PlantsSnails, slugs and wormsGardens and meadowsNo legsNot an insect, but a bug cousin

The chestnut slug is a small slug with soft, almost see-through skin. It can be light greyish brown or almost black, with fine dark spots all over. It started out in southern Italy and has now spread to gardens all around the world.

Fun fact: this one is not an insect at all, it has no legs! But kids find it on every bug hunt, so it lives in Bug Wiki too.
Lives in
First from southern Italy, now in gardens on every continent except Antarctica
Length
2 to 3.5 cm (0.79 to 1.4 in)
Top speed
about 0.02 km/h (0.01 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. Wash your hands after holding a slug, like after touching any wild animal.
What does it eat?
Like most garden slugs, it nibbles plants and is easiest to find hiding under rubbish.
For real!Photo of Chestnut slug
Picture by J. M. C. Hutchinson. CC BY-SA 3.0, via Wikimedia Commons.

How big is it?

How long is it?

Chestnut slug about 3.5 cm long (1.4 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)
as long as 6 grains of rice in a rowneeds 3 minutes to cross a dinner table

How big is Chestnut slug compared to YOU?

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

How fast is it?

cool stuff

Fun facts

1

In a big survey of gardens all over Britain, it was found in more gardens than any other slug.

2

It cannot survive when it gets colder than minus 7 degrees, so very cold winters keep it from spreading.

3

Its slime has no colour at all.

4

In cold countries like Finland, Norway and Russia, it was first found in greenhouses, where it is nice and warm.

5

Scientists used the wrong name for it for many years and only gave it its own new name in 2011.

you asked

Most asked questions about Chestnut slug

?How big is the chestnut slug?

Usually 2 to 3.5 centimetres long.

?Where does the chestnut slug live?

It started in southern Italy and now lives in gardens and greenhouses around the world.

For bug experts

Scientific name
Deroceras invadens
Group
Snails, slugs and worms
Family
Agriolimacidae
Classification
Gastropoda > Stylommatophora > Agriolimacidae
Lives on
Europe, Africa, Asia, Australia and Oceania, North America, South America

Where the facts come from

  1. Deroceras invadens (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 J. M. C. Hutchinson. CC BY-SA 3.0, 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.

Bug Wiki honey jar For grown-ups: Bug Wiki is free, with no ads and no tracking. A small tip helps keep it online.Leave a tip

More from the same group: Snails, slugs and worms

Garden snailSnails, slugs and wormsGiant African land snailSnails, slugs and wormsLeopard slugSnails, slugs and wormsBladder snailSnails, slugs and wormsMedicinal leechSnails, slugs and wormsCommon earthwormSnails, slugs and worms

Also at home here: Gardens and meadows

Eastern baton blueButterfliesCitrus looperMothsScorched carpetMothsRed chestnutMothsEastern green bush-cricketGrasshoppers and cricketsZilla orbweaverSpiders
Honey jarfor grown-ups