Common Mayfly vs Blue-Winged Olive

Side-by-side species comparison

Attribute Common Mayfly Blue-Winged Olive
Scientific Name Ephemera danica Baetis tricaudatus
Order Ephemeroptera Ephemeroptera
Family Ephemeridae Baetidae
Size 15-25 mm body 5-9 mm
Habitat Rivers & Streams Rivers & Streams
Diet Detritivores Omnivores
Regions Europe North America
Conservation Least Concern Least Concern

Common Mayfly

Adults have no functional mouths and live only 1-3 days. Massive synchronized emergences called "hatches" are among natures great spectacles. Excellent water quality indicators.

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Did You Know?

Mayflies have the shortest adult lifespan of any insect — some species live just 5 minutes as adults, long enough only to mate. They are the only insects with a winged sub-adult stage.

Blue-Winged Olive

A small olive-colored mayfly with distinctive bluish-gray wings, abundant in clean streams across North America. It produces multiple generations per year.

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Did You Know?

Blue-winged olives are among the few mayflies that hatch in winter, providing vital food for trout during cold months.