Species guide

Boxelder bug

Nuisance, not harmful

Boisea trivittata

Boxelder bug
Photo: Daniel Washburn · CC BY

How to recognise it

A black bug about 1.3 cm with three red-orange lines on the shield behind the head and red edges on the folded wings. Congregates on warm, sunny walls in autumn.

Is it dangerous?

Harmless — it doesn't bite, sting or damage the home. It can leave a reddish stain if crushed and may smell when disturbed.

What to do

Seal entry points and vacuum up any that get inside.

Recorded 39,098 times in the wild worldwide.

Think you've spotted one?

Photograph it and let SpecieSense confirm the species — and show you the reasoning.

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