Red underwing
The red underwing is a big moth with a secret. Its front wings are grey and plain, so it disappears on tree bark during the day. But when it opens them, bright red back wings with black bands flash out.
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Fun facts
When a bird finds it, it suddenly shows its red back wings. The surprise gives it time to escape.
It flies at night from summer into early autumn and comes to lights, but usually lands a little away from them.
It spends the winter as a tiny egg.
The caterpillar is grey with a reddish tint and hides between leaves it has tied together with silk when it is ready to change.
Very rarely, people have found red underwings with blue, yellow or brown back wings instead of red.
Most asked questions about Red underwing
?Why does the red underwing hide its red wings?
Its grey front wings hide it on bark during the day. It flashes the red wings only to startle an enemy.
?How big is the red underwing?
It is a large moth, with wings about 8 centimetres from tip to tip.
?What does the red underwing caterpillar eat?
It eats the leaves of willow and poplar trees.
For bug experts
- Scientific name
- Catocala nupta
- Named by
- Linnaeus, 1767
- Group
- Moths
- Family
- Erebidae
- Classification
- Insecta > Lepidoptera > Erebidae
- Lives on
- Europe, Asia
Where the facts come from
- Red underwing (Wikipedia, CC BY-SA 4.0): what it looks like, where it lives, what it eats, sizes and fun facts, retold in simple words.
- Picture by John de Haura. CC BY-SA 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 [email protected] and we will fix it.
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