Header image
Enter a name
Lateral view of a Female Hexagenia limbata (Ephemeridae) (Hex) Mayfly Dun from the Namekagon River in Wisconsin
Hex Mayflies
Hexagenia limbata

The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.

27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.
Troutnut is a project started in 2003 by salmonid ecologist Jason "Troutnut" Neuswanger to help anglers and fly tyers unabashedly embrace the entomological side of the sport. Learn more about Troutnut or support the project for an enhanced experience here.

Millcreek has attached these 4 pictures to aid in identification. The message is below.
Female. 7 mm.
Female. 7mm.
Male. 6.5 mm.
Male. 6.5 mm.
Healdsburg, CA

Posts: 344
Millcreek on Jan 24, 2015January 24th, 2015, 1:07 pm EST
This mayfly was collected from the Russian River near Healdsburg, Ca. It's common from March through October. It's usually found in shallow water 3-12 inches deep and relatively free of silt with a bottom of sand, gravel and cobble.

It's fairly easy to identify from the dorsal side of the abdomen with section five, nine and ten being mostly light in color. It's also got a mouth with labial palpi having the inner margin of segment 2 slightly convex to nearly straight as opposed to variously concave. It also has the first gill much smaller than the others.

Descriptions to genus were from Merritt, Cummins and Berg (2008). The descriptions to species were from Morihara and McCafferty (1997) "The Baetis Larvae of North America (Baetidae: Ephemeroptera).
and MacCafferty, Meyer, Randolph and Webb (2008) "Evaluation of Mayfly Species Originally Described as Baetis Leach (Ephemeroptera: Baetidae)From California.
"If we knew what it was we were doing, it would not be called research, would it?"
-Albert Einstein

Quick Reply

Related Discussions

Last Reply
Troutnut.com is copyright © 2004-2023 (email Jason). privacy policy