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.

Looking across Island Lake toward the Titcomb Basin—one of the popular crown jewels of the Wind River Mountains

From Island Lake in Wyoming

Stream photos

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Isoperla (Stripetails and Yellow Stones) Stonefly Adult Isoperla (Stripetails and Yellow Stones) Stonefly Adult

Dorsal view of a Isoperla (Perlodidae) (Stripetails and Yellow Stones) Stonefly Adult from Mystery Creek #308 in Washington

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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.

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Female Sweltsa (Sallfly) Stonefly Adult Pictures

These stoneflies--abundant during midday--seemed at first to be flying around with plain yellow bodies, but on closer inspection turn out to have striking, fiery red abdomens.

Lateral view of a Female Sweltsa (Chloroperlidae) (Sallfly) Stonefly Adult from the Madison River in Montana

Ruler view of a Female Sweltsa (Chloroperlidae) (Sallfly) Stonefly Adult from the Madison River in Montana The smallest ruler marks are 1 mm.

Female Sweltsa (Chloroperlidae) (Sallfly) Stonefly Adult from the Madison River in Montana

Ventral view of a Female Sweltsa (Chloroperlidae) (Sallfly) Stonefly Adult from the Madison River in Montana

Artistic view of a Female Sweltsa (Chloroperlidae) (Sallfly) Stonefly Adult from the Madison River in Montana

This stonefly was collected from the Madison River in Montana on June 30th, 2019 and added to Troutnut.com by Troutnut on July 17th, 2019.

Discussions of this Adult

Sweltsa?

1 replies

Posted by Taxon on Jul 17, 2019

Last reply on Jul 17, 2019 by Troutnut

Hi Jason-

My guess would be genus Sweltsa, of which I believe there to be ~8 species in MT. It looks pretty similar to a (mostly) dorsal view of Sweltsa townsesi, which is pictured in American Stoneflies: A Photographic Guide to the Plecoptera by Bill B. Stark, et. al. However, I believe that species is only present in the Northern Sierra Nevada Mountains of CA and NV.

Anyone able to ID this Chloroperlid?

Posted by Troutnut on Jul 17, 2019

Last reply on Jul 17, 2019 by Troutnut

I didn't do the best job taking pictures of key characteristics (such as wing venation), but I'm hoping somebody might be familiar with the striking color pattern. I'd love to know the species on this one.

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