Common Mayfly vs Black Mayfly

Side-by-side species comparison

Attribute Common Mayfly Black Mayfly
Scientific Name Ephemera danica Ephemera danica var. nigra
Order Ephemeroptera Ephemeroptera
Family Ephemeridae Ephemeridae
Size 15-25 mm body 15-25 mm body
Habitat Rivers & Streams Rivers & Streams
Diet Detritivores Omnivores
Regions Europe Europe
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.

💡

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.

Black Mayfly

A dark color variant of the common Green Drake mayfly found in some European populations. The dark form is more prevalent in upland, acidic waters. Important for trout feeding.

💡

Did You Know?

The dark form predominates in acidic upland streams while the typical yellow form prefers alkaline lowland rivers.