Lateral view of a Female Hexagenia limbata (Ephemeridae) (Hex) Mayfly Dun from the Namekagon River in Wisconsin

Hex Mayflies
Hexagenia limbata

The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.

Stream photos

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Coleoptera (Beetle) Insect Larva Coleoptera (Beetle) Insect Larva

Lateral view of a Coleoptera (Beetle) Insect Larva from Sears Creek in Washington

6 Recently Added Photos

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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Sweltsa onkos (Sallfly) Stonefly Adult Pictures

Ruler view of a Sweltsa onkos (Chloroperlidae) (Sallfly) Stonefly Adult from Mystery Creek #62 in New York The smallest ruler marks are 1 mm.

Lateral view of a Sweltsa onkos (Chloroperlidae) (Sallfly) Stonefly Adult from Mystery Creek #62 in New York

Sweltsa onkos (Chloroperlidae) (Sallfly) Stonefly Adult from Mystery Creek #62 in New York

Dorsal view of a Sweltsa onkos (Chloroperlidae) (Sallfly) Stonefly Adult from Mystery Creek #62 in New York

Ventral view of a Sweltsa onkos (Chloroperlidae) (Sallfly) Stonefly Adult from Mystery Creek #62 in New York

This stonefly was collected from Mystery Creek #62 in New York on May 15th, 2007 and added to Troutnut.com by Troutnut on May 18th, 2007.

Discussions of this Adult

Ontario Sallfly

Posted by GONZO on Sep 9, 2008

Last reply on Sep 9, 2008 by GONZO

I believe this is probably Sweltsa onkos. There are three Sweltsa species commonly listed for most of the Northeast (onkos, naica, and lateralis), and their individual pronotum/head markings seem rather distinctive.

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