Purple Loosestrife Beetle vs Western Water Penny

Side-by-side species comparison

Attribute Purple Loosestrife Beetle Western Water Penny
Scientific Name Galerucella calmariensis Psephenus falli
Order Coleoptera Coleoptera
Family Chrysomelidae Psephenidae
Size 4-5 mm 4-5 mm (adults)
Habitat Wetlands Mountains
Diet Herbivores Omnivores
Regions Europe (native), introduced to North America Western North America
Conservation Least Concern Least Concern

Purple Loosestrife Beetle

A small, yellowish-brown beetle deliberately introduced as a biocontrol agent against invasive purple loosestrife. Adults and larvae feed on leaves and growing tips of the target weed.

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Did You Know?

This beetle has been one of the most successful classical biological control agents, dramatically reducing purple loosestrife infestations across North America.

Western Water Penny

A water penny beetle restricted to clean mountain streams in western North America. Its disc-shaped larvae are indicators of high water quality.

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Did You Know?

The presence of water penny larvae is used by biologists as a reliable indicator that a stream is unpolluted.