Flat-headed Mayfly vs Creek Pacer Ground Beetle
Side-by-side species comparison
| Attribute | Flat-headed Mayfly | Creek Pacer Ground Beetle |
|---|---|---|
| Scientific Name | Epeorus assimilis | Chlaenius tricolor |
| Order | Ephemeroptera | Coleoptera |
| Family | Heptageniidae | Carabidae |
| Size | 10-14 mm | 10-14 mm |
| Habitat | Rivers & Streams | Rivers & Streams |
| Diet | Herbivores | Predators |
| Regions | Europe | North America, from Canada to the southern United States |
| Conservation | Least Concern | Least Concern |
Flat-headed Mayfly
A stream-dwelling mayfly nymph with a flattened body for clinging to rocks in rapids.
Did You Know?
Its flattened nymph shape allows it to live in the boundary layer of fast currents.
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.
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.