Pale Morning Dun vs Cottonwood Stag Beetle

Side-by-side species comparison

Attribute Pale Morning Dun Cottonwood Stag Beetle
Scientific Name Ephemerella excrucians Lucanus mazama
Order Ephemeroptera Coleoptera
Family Ephemerellidae Lucanidae
Size 7-10 mm 22-35 mm
Habitat Rivers & Streams Rivers & Streams
Diet Detritivores Wood Feeders
Regions North America Central and Southern United States
Conservation Least Concern Least Concern

Pale Morning Dun

A small pale yellowish mayfly that hatches in large numbers on western North American streams during late spring. It is a crucial food source for trout.

💡

Did You Know?

Pale morning duns often hatch in such dense swarms that trout become highly selective, ignoring all but perfect imitations.

Cottonwood Stag Beetle

A medium-sized North American stag beetle found near river bottoms. Males have moderately large mandibles.

💡

Did You Know?

They are most commonly found near cottonwood and willow trees along river corridors.