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.

We were lucky to be able to fish through this storm as it skirted around us to the north, giving us just enough clouds to prompt a BWO hatch but keeping the lighting at a safe distance.

From Slough Creek in Wyoming

Stream photos

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Pycnopsyche guttifera (Great Autumn Brown Sedge) Caddisfly Larva Pycnopsyche guttifera (Great Autumn Brown Sedge) Caddisfly Larva

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.

15 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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Male Tallaperla maria (Common Roachfly) Stonefly Adult Pictures

The adult stoneflies of this family look surprisingly normal given the strange shape of the nymphs. I tried to identify it beyond family level 15 years after collecting it, based on my photos, which are not ideal. It's difficult even to tell the gender for sure because I don't have a good picture of the terminalia, but the body size suggests it's a male, and the species ranges suggest either Peltoperla arcuata or a male Tallaperla maria. One distinctive feature of the original description of this species is that the antennae are paler for a short distance beyond the first two thick, dark segments. That can be seen on this specimen and on a specimen on BugGuide identified as Tallaperla maria.