Brown Marmorated Stink Bug
Halyomorpha halys
A marbled shield that smells when bothered
This shield-shaped true bug from East Asia sucks the sap of fruit trees and seed pods with a needle beak. Carried accidentally to North America and Europe, it became a serious orchard pest, defended by the foul fluid that gave stink bugs their name.
Key figures
- Size
- Adults about 12–17 mm long
- Mouthparts
- A needle-like beak stabs under fruit skin to drink sap
- Defence
- Scent glands vent foul-smelling fluid when disturbed
- Habitat
- Orchards, fields and forest edges; houses in autumn
- Life cycle
- Breeds through summer; adults hide in cracks over winter
- Feature
- Marbled back, big triangular scutellum, pale-banded antennae
Life cycle
Egg → Nymph → Adult
Ecological role
It drains sap from dozens of crops and wild plants, and is chased in turn by birds, spiders and parasitic wasps.
Did you know
On autumn evenings it slips through window seals to spend winter in wall voids, waking on warm indoor days and buzzing at lamps.
Range
Native to East Asia; invasive in North America and Europe
Status
Abundant; a notable invasive pest
Anatomy
- Scutellum — A large triangular plate between the wing bases — the classic shield-bug badge
- Pronotum — The broad shoulder plate behind the head is marbled ("marmorated") in shades of brown
- Rostrum — A jointed needle folded beneath the body, stabbing fruit to pump out sap
- Antenna — Dark segments ringed with pale bands — a quick field mark against native look-alikes
- Abdomen — The flat underside hides gland openings; nymphs carry extra scent glands along the back
- Legs — Clawed feet grip leaves and fruit while feeding parties cluster on ripening crops
Open the interactive 3D specimen