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.
Featured on the forum
This species was fairly abundant in a February sample of the upper Yakima.
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.
GONZO on Jul 19, 2011July 19th, 2011, 4:10 am EDT
This looks more like a Leucrocuta nymph to me (possibly L. hebe?).
Troutnut on Jul 19, 2011July 19th, 2011, 9:37 am EDT
Thanks, you're right on the genus for sure. There's no fibrilliform portion on gill 7, and the tails only have spines at the segments. I'd guess you're right on the species too but I don't know.
Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist
Troutnut and salmonid ecologist
GONZO on Jul 19, 2011July 19th, 2011, 4:24 pm EDT
It's difficult to be certain of the species, Jason. If reliable keys to the nymphs exist, I haven't seen them, and McCafferty (2004) says that some of the species are "questionably valid."