Light Cahill Mayfly vs Green Drake Mayfly

Side-by-side species comparison

Attribute Light Cahill Mayfly Green Drake Mayfly
Scientific Name Heptagenia solitaria Ephemera guttulata
Order Ephemeroptera Ephemeroptera
Family Heptageniidae Ephemeridae
Size 9-13 mm 18-25 mm
Habitat Rivers & Streams Rivers & Streams
Diet Omnivores Omnivores
Regions North America Eastern North America
Conservation Least Concern Least Concern

Light Cahill Mayfly

A pale-colored mayfly highly prized by fly fishers for imitating hatches. Nymphs prefer moderate current over gravel substrates.

💡

Did You Know?

The Light Cahill dry fly pattern, designed to mimic this species, has been used since the 1880s.

Green Drake Mayfly

A large and strikingly beautiful mayfly with mottled wings that emerges in late spring. Its hatches on eastern North American streams create some of the year's best fly-fishing opportunities.

💡

Did You Know?

Green drake hatches trigger a feeding frenzy among trout, with even the largest fish rising to the surface.