Header image
Enter a name
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.

Case view of a Pycnopsyche guttifera (Limnephilidae) (Great Autumn Brown Sedge) Caddisfly Larva from the Yakima River in Washington
It's only barely visible in one of my pictures, but I confirmed under the microscope that this one has a prosternal horn and the antennae are mid-way between the eyes and front of the head capsule.

I'm calling this one Pycnopsyche, but it's a bit perplexing. It seems to key definitively to at least Couplet 8 of the Key to Genera of Limnephilidae Larvae. That narrows it down to three genera, and the case seems wrong for the other two. The case looks right for Pycnopsyche, and it fits one of the key characteristics: "Abdominal sternum II without chloride epithelium and abdominal segment IX with only single seta on each side of dorsal sclerite." However, the characteristic "metanotal sa1 sclerites not fused, although often contiguous" does not seem to fit well. Those sclerites sure look fused to me, although I can make out a thin groove in the touching halves in the anterior half under the microscope. Perhaps this is a regional variation.

The only species of Pycnopsyche documented in Washington state is Pycnopsyche guttifera, and the colors and markings around the head of this specimen seem to match very well a specimen of that species from Massachusetts on Bugguide. So I am placing it in that species for now.

Whatever species this is, I photographed another specimen of seemingly the same species from the same spot a couple months later.
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.

Peltoperla (Roachfly) Stonefly Nymph Pictures

I'm guessing this is an immature Peltoperla, because it lacks the well-developed setal fringe on the hind femora that would indicate Tallaperla, but it also lacks the dark spots that should indicate a mature Peltoperla nymph.

Peltoperlidae stonefly nymph. This odd-shaped stonefly family is also known was the "roachflies"

Dorsal view of a Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York
Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York
Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York
Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York
Ventral view of a Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York
Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York
Ruler view of a Peltoperla (Peltoperlidae) (Roachfly) Stonefly Nymph from Mystery Creek #62 in New York The smallest ruler marks are 1 mm.

This stonefly was collected from Mystery Creek #62 in New York on April 1st, 2007 and added to Troutnut.com by Troutnut on April 3rd, 2007.


Start a Discussion of Nymph

Peltoperla (Roachfly) Stonefly Nymph Pictures

Collection details
Location: Mystery Creek #62, New York
Date: April 1st, 2007
Added to site: April 3rd, 2007
Author: Troutnut
Troutnut.com is copyright © 2004-2024 (email Jason). privacy policy