Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York

Blue-winged Olives
Baetis

Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.

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.

Burrowing mayfly

Willmilne has attached these 3 pictures to aid in identification. The message is below.

Willmilne
Manitoba Canada

Posts: 19

Willmilne on Sep 28, 2008September 28th, 2008, 2:51 pm EDT

Not sure but I think this is a E.Simulans

Manitoba Canada

Taxon

Site Editor
Plano, TX

Posts: 1311

Taxon on Sep 28, 2008September 28th, 2008, 3:39 pm EDT

Will-

Right, you are. Really nice photos.

Best regards,
Roger Rohrbeck
www.FlyfishingEntomology.com

Beardius
Posts: 19

Beardius on Dec 4, 2008December 4th, 2008, 8:14 pm EST

It looks like it recently molted and hasn't attained it's full color.

Troutnut

Administrator
Bellevue, WA

Posts: 2758

Troutnut on Dec 5, 2008December 5th, 2008, 7:51 am EST

Excellent photos!!

Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist

JZord
New York

Posts: 14

JZord on Mar 4, 2009March 4th, 2009, 7:57 am EST

where do they burrow?

Taxon

Site Editor
Plano, TX

Posts: 1311

Taxon on Mar 4, 2009March 4th, 2009, 11:39 am EST

Juntin-

Current Speed: Slow to medium
Substrate: Sand and fine gravel, sometimes silt

You may want to acquaint yourself better with the Aquatic Insects portion of this site. For example, here is a link to the page for Ephemera simulans.

Best regards,
Roger Rohrbeck
www.FlyfishingEntomology.com