Slate Maroon Drakes

There is remarkable variety of form and color within this prolific genus of fast-water mayflies. Different species are found across the country, and several cause good hatches. Fly anglers are likely to encounter the lesser species on occasion, too.

The best Epeorus hatch in the East is Epeorus pleuralis, the famous Quill Gordon, the first abundant large mayfly hatch of the year. Epeorus vitreus comes a little later and is important in both the East and Midwest.

In the West, Epeorus longimanus dominates in fast, high-altitude streams, while Epeorus albertae inhabits slower and lower waters.

This large, relatively uncommon Western mayfly may produce short fishable hatches. Ernest Schwiebert remarked in Matching the Hatch about its unique appearance:

This large dark mayfly is one of the most unusually colored insects to hatch on Western streams, for its sternites (

One sternite of this Isonychia bicolor mayfly spinner is highlighted in red.

Sternite: The bottom (ventral) part of a single segment on an insect's abdomen.) are a reddish maroon.