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Sticker of Red triangle slug
Bug card No. 1129 of 1,500

Red triangle slug

Triboniophorus graeffei
Eats: PlantsSnails, slugs and wormsForests and woodsNo legsNot an insect, but a bug cousin

The red triangle slug is Australia's biggest native land slug. It can be white, yellow, grey, pink or green, but every grown-up has a red triangle on its back and a red line around its foot. Its back has a pattern like the veins of a leaf.

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
The east coast of Australia, in damp forests, woodlands and city gardens
Length
14 to 15 cm (5.5 to 5.9 in)
Top speed
about 0.03 km/h (0.02 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 grazes on the thin green algae that grow on smooth gum tree bark and rocks. Sometimes it sneaks into houses and eats mould off bathroom walls.
For real!Photo of Red triangle slug
Picture by (c) Sue Carnahan, some rights reserved (CC BY). CC BY 4.0, via Wikimedia Commons.

How big is it?

How long is it?

Red triangle slug about 15 cm long (5.9 in)A crayon about 9 cm (3.5 in)A banana about 18 cm (7.1 in)A house cat about 50 cm (20 in)
as long as 5 toy building bricks in a rowabout as long as your handneeds 2 minutes to cross a dinner table

How big is Red triangle slug 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 is in danger, it makes a special super sticky slime that can glue an attacker stuck for days.

2

It has only two feelers on its head. Most slugs have four.

3

Babies do not have the red triangle yet. They have three dark grey stripes down their back instead.

4

You can sometimes see the tracks where it has scraped algae off tree trunks.

5

It can grow up to 15 centimetres long, almost as long as a pencil.

you asked

Most asked questions about Red triangle slug

?Is the red triangle slug dangerous?

No. It is harmless, but wash your hands after touching it.

?How big is the red triangle slug?

It can grow up to about 15 centimetres long.

?What does the red triangle slug eat?

Algae from tree bark and rocks, and sometimes mould inside houses.

For bug experts

Scientific name
Triboniophorus graeffei
Named by
Humbert
Group
Snails, slugs and worms
Family
Athoracophoridae
Classification
Gastropoda > Stylommatophora > Athoracophoridae
Lives on
Australia and Oceania

Where the facts come from

  1. Red triangle slug (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 (c) Sue Carnahan, some rights reserved (CC BY). 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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