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Sticker of Common eastern firefly
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Common eastern firefly

Photinus pyralis
Name means: “big dipper comes from the male's flight, a J-shaped swoop that lights up on the way up”

The common eastern firefly is a small soft beetle with a light in its tummy. On summer evenings the males fly around blinking, drawing glowing J shapes in the air. The females sit in the grass and blink back if they like what they see.

Lives in
Eastern North America, in meadows, fields, wetlands and woods
Length
0.9 to 1.9 cm (0.35 to 0.75 in)
Top speed
about 3.8 km/h (2.4 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless. It cannot bite or sting. If you catch one, let it go again so it can keep blinking.
What does it eat?
The larvae live under the soil and eat worms, slugs and snails.
For real!Photo of Common eastern firefly
Picture by art farmer from evansville indiana, usa. CC BY-SA 2.0, via Wikimedia Commons.

How big is it?

How long is it?

Common eastern firefly about 1.9 cm long (0.75 in)A grain of rice about 6 mm (0.24 in)A toy building brick about 3.2 cm (1.3 in)A crayon about 9 cm (3.5 in)
as long as 3 grains of rice in a rowcould fly across a whole football pitch in 99 secondsmoves 56 times its own body length every second

How big is Common eastern firefly compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

It is the most common firefly in North America.

2

The babies glow too. Their light warns hungry animals to stay away.

3

It tastes horrible to birds and bats, because its body has special bad-tasting chemicals.

4

A larva can live under the ground for up to two years before it changes into a beetle.

5

Its biggest dangers are bright lights at night, poisons sprayed on plants and building on the places where it lives.

you asked

Most asked questions about Common eastern firefly

?Why do fireflies light up?

They blink to find a mate. The males flash while flying, and the females answer from the grass.

?What do fireflies eat?

The larvae eat worms, slugs and snails under the soil.

?How long does a firefly live?

As a grown-up beetle it lives about three weeks to two months, but it can spend up to two years as a larva.

For bug experts

Scientific name
Photinus pyralis
Group
Beetles
Family
Lampyridae
Classification
Insecta > Coleoptera > Lampyridae
Lives on
North America
Also known as
Big dipper firefly, Lightning bug

Where the facts come from

  1. Photinus pyralis (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 art farmer from evansville indiana, usa. CC BY-SA 2.0, 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 [email protected] and we will fix it.

More from the same group: Beetles

Also at home here: Gardens and meadows