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Sticker of Alligatorweed flea beetle
Bug card No. 0050 of 4,939

Alligatorweed flea beetle

Agasicles hygrophila
Eats: PlantsBeetlesPonds, rivers and shores6 legs

The alligatorweed flea beetle is a small black beetle with yellow stripes on its back. It is a helper beetle. People bring it to rivers and lakes to eat a weed that clogs up the water.

Lives in
From South America, now also in the southeastern United States and New Zealand, on waterways
Length
5 mm (0.2 in)
Top speed
about 0.29 km/h (0.18 mph)
On foot, estimate
Can it hurt you?
Harmless
Harmless. It does not bite people or sting.
What does it eat?
It eats only the leaves of alligator weed, a plant that grows in thick mats on water. Both the beetles and their yellow larvae munch the leaves.
For real!Photo of Alligatorweed flea beetle
Picture by Gary Buckingham, USDA Agricultural Research Service. Public domain, via Wikimedia Commons.

How big is it?

How long is it?

Alligatorweed flea beetle about 5 mm long (0.2 in)A grain of rice about 6 mm (0.24 in)
small enough to sit on your fingernailcould run across a dinner table in 12 seconds

How big is Alligatorweed flea beetle compared to YOU?

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

How fast is it?

cool stuff

Fun facts

1

One female lays about 1,000 eggs in her short life of six weeks.

2

She lays her tiny eggs in neat rows on the leaves.

3

When the beetles eat all the leaves of a weed mat, the weed dies and the water is clear again.

4

Using one living thing to stop a pest is called biological control, and this beetle is a famous success.

you asked

Most asked questions about Alligatorweed flea beetle

?Why do people use the alligatorweed flea beetle?

It eats alligator weed, a plant that clogs rivers and lakes, and helps clear the water.

?Is the alligatorweed flea beetle dangerous?

No. It is harmless to people and only eats alligator weed.

For bug experts

Scientific name
Agasicles hygrophila
Group
Beetles
Family
Chrysomelidae
Classification
Insecta > Coleoptera > Chrysomelidae
Lives on
South America, North America, Australia and Oceania
Also known as
Alligator weed flea beetle

Where the facts come from

  1. Agasicles hygrophila (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 Gary Buckingham, USDA Agricultural Research Service. Public domain, 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: Beetles

Also at home here: Ponds, rivers and shores

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