Giant Michigan Mayfly vs Pale Evening Dun

Side-by-side species comparison

Attribute Giant Michigan Mayfly Pale Evening Dun
Scientific Name Hexagenia bilineata Heptagenia adaequata
Order Ephemeroptera Ephemeroptera
Family Ephemeridae Heptageniidae
Size 18-28 mm 8-12 mm
Habitat Rivers & Streams Rivers & Streams
Diet Detritivores Omnivores
Regions North America Europe
Conservation Least Concern Least Concern

Giant Michigan Mayfly

A large burrowing mayfly with two dark stripes on its thorax. Nymphs dig into soft clay and silt bottoms of large rivers.

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Did You Know?

Mass emergences along the Great Lakes have caused road closures due to the slippery accumulation of millions of dead adults.

Pale Evening Dun

A flat-bodied mayfly whose nymphs press tightly against rocks in swift currents. Adults emerge at dusk during summer months.

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Did You Know?

Its extremely flattened body allows it to resist currents that would sweep away most other insects.