Bug Wiki
Bug Wiki / All bugs / Snails, slugs and worms
Sticker of Horse leech
Bug card No. 0747 of 1,500

Horse leech

Haemopis sanguisuga
Eats: Other bugs and small animalsSnails, slugs and wormsPonds, rivers and shoresNo legsNot an insect, but a bug cousin

The horse leech is a long, slippery, brownish-black worm that lives in ponds and slow rivers. It has a sucker at each end of its body and ten little eyes on its head. Despite its scary name, it does not suck blood 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
Most of Europe and parts of Asia, in ponds, lakes, ditches and slow rivers
Length
10 cm (3.9 in)
Top speed
about 0.03 km/h (0.02 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. It has only a few blunt teeth and does not suck blood from people.
What does it eat?
It hunts small water animals like insect larvae, worms, snails, tadpoles and fish eggs, and swallows them whole. Sometimes it crawls out of the water to catch earthworms.
For real!Photo of Horse leech
Picture by Holger Krisp. CC BY 3.0, via Wikimedia Commons.

How big is it?

How long is it?

Horse leech 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 Horse leech compared to YOU?

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

How fast is it?

cool stuff

Fun facts

1

It moves like an inchworm: front sucker down, back sucker forward, then stretch again.

2

It can also swim, and it can crawl up to 30 metres away from the water.

3

It can stretch out even longer than its normal 10 centimetres.

4

Each leech is both a mum and a dad at the same time.

5

It lays its eggs in a little cocoon buried in damp earth by the water.

you asked

Most asked questions about Horse leech

?Does the horse leech suck blood?

No. It eats small animals like worms and insect larvae and swallows them whole.

?How big is a horse leech?

About 10 centimetres long, and even longer when it stretches.

?Where do horse leeches live?

In ponds, lakes, ditches and slow rivers in Europe and Asia.

Myth buster

Myth: The horse leech sucks blood from horses.

Truth: No. It got its name because it looks like another leech that bothers animals. The horse leech is a hunter that swallows small animals whole.

For bug experts

Scientific name
Haemopis sanguisuga
Named by
Linnaeus, 1758
Group
Snails, slugs and worms
Family
Haemopidae
Classification
Clitellata > Arhynchobdellida > Haemopidae
Lives on
Europe, Asia

Where the facts come from

  1. Haemopis sanguisuga (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 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.

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: Ponds, rivers and shores

Common stretch spiderSpidersLesser water boatmanTrue bugs and cicadasCrimson marsh gliderDragonflies and damselfliesHeike fireflyBeetlesKatipōSpidersDiving bell spiderSpiders