Elm Seed Bug vs Horned Aphid

Side-by-side species comparison

Attribute Elm Seed Bug Horned Aphid
Scientific Name Arocatus melanocephalus Tuberaphis styraci
Order Hemiptera Hemiptera
Family Lygaeidae Hormaphididae
Size 6-7 mm 1-2.5 mm
Habitat Underground Forests
Diet Seed Feeders Sap Feeders
Regions Europe (native), Northwestern North America (invasive) Japan, East Asia
Conservation Least Concern Not Evaluated

Elm Seed Bug

A small seed bug native to southern Europe that has become an invasive nuisance pest in the northwestern United States. It aggregates in enormous numbers on and inside buildings in summer and fall.

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Did You Know?

Thousands can invade a single home seeking shelter, producing a foul odor when disturbed or crushed.

Horned Aphid

A social aphid from East Asia that forms colonies defended by sterile soldier nymphs with horned heads. They live on styrax trees and produce a single soldier caste.

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Did You Know?

Soldiers stab intruders with their sharp horns and inject a toxic secretion, dying in the process like a honeybee's suicide sting.