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Sticker of Ilia underwing
Bug card No. 0764 of 1,500

Ilia underwing

Catocala ilia
Name means: “underwing is for its bright back wings, which hide under the front wings”
Eats: PlantsMothsForests and woods6 legs

The Ilia underwing is a big moth with grey and brown front wings. When it opens them, it shows a surprise: bright orange or red back wings with black stripes. On each front wing there is a spot with a neat white ring around it.

Lives in
Eastern United States and southern Canada, in oak woods
Wingspan
6.5 to 8.2 cm (2.6 to 3.2 in)
Top speed
about 20 km/h (12 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless. It cannot bite or sting.
What does it eat?
Its caterpillars munch oak leaves, from black, bur, red and white oak trees.
For real!Photo of Ilia underwing
Picture by NCBioTeacher. CC0, via Wikimedia Commons.

How big is it?

How wide are its wings?

Ilia underwing wings about 8.2 cm tip to tip (3.2 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)
wings as wide as 2.5 toy building brickscould fly across a whole football pitch in 19 seconds

How big is Ilia underwing compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

Its hidden back wings can be light orange or deep red.

2

The front wings can look very different from one moth to the next, but the white ringed spot helps you know it.

3

It flies from June to September, depending on where it lives.

4

A different kind of it lives far away in California and Arizona.

you asked

Most asked questions about Ilia underwing

?What does the Ilia underwing eat?

Its caterpillars eat the leaves of oak trees.

?How big is the Ilia underwing?

Its wings are about 6.5 to 8 centimetres from tip to tip.

For bug experts

Scientific name
Catocala ilia
Named by
Cramer, 1776
Group
Moths
Family
Erebidae
Classification
Insecta > Lepidoptera > Erebidae
Lives on
North America
Also known as
Beloved underwing, Wife underwing

Where the facts come from

  1. Catocala ilia (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 NCBioTeacher. CC0, 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: Moths

Also at home here: Forests and woods