Elm Seed Bug vs Eastern Bat Bug

Side-by-side species comparison

Attribute Elm Seed Bug Eastern Bat Bug
Scientific Name Arocatus melanocephalus Cimex adjunctus
Order Hemiptera Hemiptera
Family Lygaeidae Cimicidae
Size 6-7 mm 4-5 mm
Habitat Underground Gardens
Diet Seed Feeders Blood Feeders
Regions Europe (native), Northwestern North America (invasive) Eastern North America
Conservation Least Concern Least Concern

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.

Eastern Bat Bug

A blood-feeding ectoparasite primarily of bats in eastern North America. It can bite humans when bat colonies are removed from buildings.

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Did You Know?

It is nearly indistinguishable from the common bed bug and requires microscopic examination to tell apart.