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Sticker of Bladder snail
Bug card No. 0145 of 1,500

Bladder snail

Physella acuta
Name means: “acuta is Latin for sharp”
Eats: Leftovers and dead thingsSnails, slugs and wormsPonds, rivers and shoresNo legsNot an insect, but a bug cousin

The bladder snail is a small water snail with a thin, shiny, pointy shell. Its shell curls to the left, while most snails curl to the right. It breathes air, so it comes up to the surface now and then.

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 North America, now in ponds, ditches and aquariums on every continent except Antarctica
Length
9 mm (0.35 in)
the width of the shell
Top speed
about 0.02 km/h (0.01 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. Wash your hands after touching pond water or snails.
What does it eat?
It eats leftovers and dead bits in the water, and the slimy green algae that grow on stones and glass.
For real!Photo of Bladder snail
Picture by Dat doris. CC BY-SA 4.0, via Wikimedia Commons.

How big is it?

How long is it?

Bladder snail about 9 mm long (0.35 in)A grain of rice about 6 mm (0.24 in)A toy building brick about 3.2 cm (1.3 in)
small enough to sit on your fingernailas long as 1.5 grains of rice in a rowneeds 3 minutes to cross a dinner table

How big is Bladder snail 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 the most widespread freshwater snail in the world.

2

When something attacks it, it can twist its shell back and forth very fast.

3

If there are hungry animals around, it grows a thicker shell to stay safe.

4

It can have babies even when it is all alone.

5

It probably first travelled to Europe with cotton shipments in the 1700s.

you asked

Most asked questions about Bladder snail

?How big is a bladder snail?

Its shell grows up to about 16 millimetres long and 9 millimetres wide.

?Are bladder snails good for an aquarium?

A few can help by eating leftovers and algae, but they have babies so fast that they can soon fill the tank.

?Can bladder snails live in dirty water?

Yes. They can live in polluted water with little oxygen, where many other snails cannot.

For bug experts

Scientific name
Physella acuta
Named by
Draparnaud, 1805
Group
Snails, slugs and worms
Family
Physidae
Classification
Gastropoda > Hygrophila > Physidae
Lives on
North America, Europe, Asia, Africa, South America, Australia and Oceania
Also known as
European physa, Tadpole snail, Sewage snail, Acute bladder snail

Where the facts come from

  1. Physella acuta (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 Dat doris. CC BY-SA 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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