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

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

Dorsal view of a Setvena wahkeena (Perlodidae) (Wahkeena Springfly) Stonefly Nymph from Mystery Creek #199 in Washington
As far as I can tell, this species has only previously been reported from one site in Oregon along the Columbia gorge. However, the key characteristics are fairly unmistakable in all except for one minor detail:
— 4 small yellow spots on frons visible in photos
— Narrow occipital spinule row curves forward (but doesn’t quite meet on stem of ecdysial suture, as it's supposed to in this species)
— Short spinules on anterior margin of front legs
— Short rposterior row of blunt spinules on abdominal tergae, rather than elongated spinules dorsally
I caught several of these mature nymphs in the fishless, tiny headwaters of a creek high in the Wenatchee Mountains.
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.

Posts: 24
Isidro on Mar 27, 2008March 27th, 2008, 1:09 am EDT
I think that this one can be impossible...

Sabiñanigo, NE Spain. Fresh mountain-climate, about 900 meters. River: with many trees and hedges in the sides. Contaminated, slow, with some lime and big stones, without water weeds, not deep. Mayfly: about 11-12 mm. wingspan, Three cerci, of very clear colour, very dark body, turbinate eyes.

Some helps can be given?
Taxon's profile picture
Site Editor
Plano, TX

Posts: 1311
Taxon on Mar 27, 2008March 27th, 2008, 3:09 am EDT

My guess would be a species in family Leptophlebiidae. The fact that the median filament is longer than the cerci should identify it rather easily for someone familiar with European mayflies. I recommend you ask Dr. Nikita J. Kluge of St. Petersburg University.

Edit: Now that I look at the photo again, I suspect the tails may actually be of equal length, and the angle of the photo makes it appear they are not. In any event, that impacts neither my guess as to family, nor my recommendation for consultation.
Best regards,
Roger Rohrbeck
Posts: 24
Isidro on May 4, 2008May 4th, 2008, 2:56 am EDT
Thanks Roger. I see that adult mayflies are more difficult taht I supposed...

Quick Reply

Related Discussions

Last Reply
Sep 15, 2006
by Troutnut
Troutnut.com is copyright © 2004-2023 (email Jason). privacy policy