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Sticker of Northern dusky slug
Bug card No. 3028 of 4,939

Northern dusky slug

Arion fuscus
Eats: A bit of everythingSnails, slugs and wormsForests and woodsNo legsNot an insect, but a bug cousin

The northern dusky slug is a brown roundback slug. It can be dark brown, olive, orange or bright reddish orange. Its slime is special: it is yellow-orange.

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
Central, northern and eastern Europe, China, and brought to eastern North America
Length
5 to 7 cm (2 to 2.8 in)
Top speed
about 0.02 km/h (0.01 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. Wash your hands after touching it, like after touching any wild animal.
What does it eat?
It eats almost anything: fungi, dying leaves, fruit, dead insects and worms, and even animal poo.
For real!Photo of Northern dusky slug
Picture by Holger Krisp. CC BY 3.0, via Wikimedia Commons.

How big is it?

How long is it?

Northern dusky slug about 7 cm long (2.8 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 2 toy building bricks in a rowneeds 3 minutes to cross a dinner table

How big is Northern dusky slug compared to YOU?

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

How fast is it?

cool stuff

Fun facts

1

It is most busy at dusk, when the light fades.

2

In winter it burrows into the soil, and in summer it hides from the dry heat.

3

It usually lives only 8 to 12 months.

4

It is the most common slug brought from abroad in eastern North America.

5

It looks just like its western cousin. Scientists can only tell them apart by their genes or inner organs.

you asked

Most asked questions about Northern dusky slug

?How big is the northern dusky slug?

About 5 to 7 centimetres long.

?What does the dusky slug eat?

Almost anything: fungi, old leaves, fruit, dead insects and worms, and animal poo.

For bug experts

Scientific name
Arion fuscus
Group
Snails, slugs and worms
Family
Arionidae
Classification
Gastropoda > Stylommatophora > Arionidae
Lives on
Europe, Asia, North America
Also known as
Dusky arion, Dusky slug, Northern dusky arion

Where the facts come from

  1. Arion fuscus (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 Holger Krisp. CC BY 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.

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More from the same group: Snails, slugs and worms

Also at home here: Forests and woods

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