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Sticker of Spotted keeled slug
Bug card No. 4113 of 4,939

Spotted keeled slug

Tandonia rustica
Eats: PlantsSnails, slugs and wormsForests and woodsNo legsNot an insect, but a bug cousin

The spotted keeled slug is a big pale slug covered in lots of little black dots. Along its back runs a ridge called a keel, like the bottom of a boat. It has no shell at all.

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 Europe, and now also Britain, Ireland and other parts of Europe, in hilly forests
Length
7 to 10 cm (2.8 to 3.9 in)
Top speed
about 0.03 km/h (0.02 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless to people. Wash your hands after touching any slug.
What does it eat?
It eats plants. People worry it could harm crops in places where it does not belong.
For real!Photo of Spotted keeled slug
Picture by Francisco Welter Schultes. CC BY-SA 3.0, via Wikimedia Commons.

How big is it?

How long is it?

Spotted keeled slug about 10 cm long (3.9 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 3 toy building bricks in a rowabout as long as your handneeds 2 minutes to cross a dinner table

How big is Spotted keeled 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 can be creamy white, reddish or yellowish grey, always with many black dots.

2

The keel on its back is yellowish to white, and the bottom of its foot is cream.

3

It likes forests on mountain slopes with lots of broken limestone rocks.

4

It does not live in the United States, and experts there want to keep it out because it could become a pest.

you asked

Most asked questions about Spotted keeled slug

?How big is the spotted keeled slug?

It grows to about 7 to 10 centimetres long.

?Is the spotted keeled slug harmful?

Not to people. But it eats plants, so it could become a pest on farms in new places.

For bug experts

Scientific name
Tandonia rustica
Group
Snails, slugs and worms
Family
Milacidae
Classification
Gastropoda > Stylommatophora > Milacidae
Lives on
Europe

Where the facts come from

  1. Tandonia rustica (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 Francisco Welter Schultes. 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.

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