Creek Pacer Ground Beetle vs Giant Stonefly

Side-by-side species comparison

Attribute Creek Pacer Ground Beetle Giant Stonefly
Scientific Name Chlaenius tricolor Pteronarcys californica
Order Coleoptera Plecoptera
Family Carabidae Pteronarcyidae
Size 10-14 mm 30-50 mm body
Habitat Rivers & Streams Rivers & Streams
Diet Predators Herbivores
Regions North America, from Canada to the southern United States North America
Conservation Least Concern Least Concern

Creek Pacer Ground Beetle

A handsome ground beetle with bright metallic green elytra, a bluish pronotum, and reddish-brown legs. It is commonly found near streams and rivers across North America.

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Did You Know?

Like other Chlaenius species, it produces a strong, distinctive odor from defensive glands that some collectors describe as smelling like leather or wet dog.

Giant Stonefly

Large aquatic insects whose nymphs require pristine, cold, oxygen-rich streams. Adults are poor fliers and stay near water. Important food source for trout.

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Did You Know?

Stonefly nymphs are so sensitive to water pollution that their presence is used by scientists as a living indicator of water quality — no stoneflies means polluted water.