Artistic view of a Male Pteronarcys californica (Pteronarcyidae) (Giant Salmonfly) Stonefly Adult from the Gallatin River in Montana

Salmonflies
Pteronarcys californica

The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.

Stream photos

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Onocosmoecus (Great Late-Summer Sedge) Caddisfly Larva Onocosmoecus (Great Late-Summer Sedge) Caddisfly Larva

Lateral view of a Onocosmoecus (Limnephilidae) (Great Late-Summer Sedge) Caddisfly Larva from the Yakima River in Washington

This specimen keys pretty easily to Onocosmoecus, and it closely resembles a specimen from Alaska which caddis expert Dave Ruiter recognized as this genus. As with that specimen, the only species in the genus documented in this area is Onocosmoecus unicolor, but Dave suggested for that specimen that there might be multiple not-yet-distinguished species under the unicolor umbrella and it would be best to stick with the genus-level ID. I'm doing the same for this one.

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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.

Ephemera simulans (Brown Drake) Mayfly Nymph Pictures

Video Clip

Ephemera 1

Featuring: Ephemera simulans Mayfly Nymph

Shot on Jan 12, 2004

Added by Troutnut on Mar 30, 2006

This mayfly was collected from the Namekagon River in Wisconsin on January 31st, 2004 and added to Troutnut.com by Troutnut on January 25th, 2006.

Discussions of this Nymph

Nice pictures of accompanying Epoicocladius sp. larvae

3 replies

Posted by Beardius on Aug 1, 2008

Last reply on Aug 8, 2008 by Beardius

Several of these pictures show larvae of the midge Epoicocladius (Diptera: Churonomidae: Orthocladiinae) attached to the gills of the nymph. This species is an obligate commensal that feeds on organic material that accumulates on hair tufts at the base of the gills. They are almost always present where burrowing mayflies are present in large numbers. Different species of Epoicocladius are found on Ephemera spp., Hexagenia spp., and Litobrancha sp.

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