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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.

Dorsal view of a Glossosoma (Glossosomatidae) (Little Brown Short-horned Sedge) Caddisfly Larva from the Yakima River in Washington
I caught this tiny larva without a case, but it seems to key pretty clearly to to Glossosomatidae. From there, the lack of sclerites on the mesonotum points to either Glossosoma or Anagapetus. Although it's difficult to see in a 2D image from the microscope, it's pretty clear in the live 3D view that the pronotum is only excised about 1/3 of its length to accommodate the forecoxa, not 2/3, which points to Glossosoma at Couplet 5 of the Key to Genera of Glossosomatidae Larvae.
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.

Male Isoperla fulva (Yellow Sally) Stonefly Adult Pictures

Family-level ID following Merritt, Cummins, & Berg 5th Edition:
1. Thoracic gill remnants absent
2. Arms of mesosternal Y-ridge approach posterior end of furcal pits
3. Submental gill remnants short, obscure, or absent
4. Male. Note that sternum 9 (the long, dark, last segment) appears to be the 8th if you count from the front in the ventral view, because the first segment is not easily visible ventrally.
5. Male abdominal tergum 10 not divided posteriorly; Paraprocts modified as hooks.
6. Male abdominal tergum 10 simple without notches or other prominent processes. This one was tricky, because at first glance it looks like the hooks arise from tergum 10, but in fact they're coming from the paraprocts underneath. There's a medial groove on tergum 10 that could be seen as a "notch" too, but it seems by "notch" the key is referring to a notch in the margin.
7. Abdominal sternum 8 with a conspicuous lobe and sternum 7 without such a lobe.
This leads to Isoperla.
Among Isoperla species known in Washington, most species are ruled out by different shapes of the vesicle (the rounded posterior bump on sternum 8). Isoperla pinta is ruled out by the lack of a region of stout spinules on tergum 9. The remaining options (without knowing how to properly dissect and image the aedeagus) are Isoperla fulva, Isoperla marmorata, Isoperla tilasqua, and Isoperla gravitans, the latter of which is too large. The other three are all at least slim possibilities, but several described characteristics seem to best match Isoperla fulva, which is also mentioned as the most common western Isoperla.

Artistic view of a Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Ventral view of a Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Ruler view of a Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington The smallest ruler marks are 1 mm.
Dorsal view of a Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
The red box shows the paraprocts extending above tergum 10.

Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington
Dorsal view of one of the cerci, showing the single row of setae on the other side

Male Isoperla fulva (Perlodidae) (Yellow Sally) Stonefly Adult from Mystery Creek #295 in Washington

This stonefly was collected from Mystery Creek #295 in Washington on May 31st, 2022 and added to Troutnut.com by Troutnut on June 1st, 2022.


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Male Isoperla fulva (Yellow Sally) Stonefly Adult Pictures

Collection details
Location: Mystery Creek #295, Washington
Date: May 31st, 2022
Added to site: June 1st, 2022
Author: Troutnut
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