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Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York
Blue-winged Olives

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.

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.

Dorsal view of a Female Dolophilodes distincta (Philopotamidae) (Tiny Black Gold Speckled-Winged Caddis) Caddisfly Adult from Brodhead Creek in Pennsylvania
This is a really strange specimen. I would guess it's one of the dry caddis pupa that scoots across the surface of the water as a pupa rather than emerging right away. Its "wing pads" sure don't look right, though. Maybe they're deformed and that's why I was able to find this one as a pupa in the first place. It also looks like it might be a caddis adult missing its wings, but since I found three of them, that kind of rules out such an anomalous maiming.

I found this one and one other on a midstream rock. The previous day, I caught a similar creature kicking around on the water's surface.

This one died and shriveled a little bit before I could photograph it, but it's basically in its original shape.
Posts: 1
Ictodd on Jun 7, 2007June 7th, 2007, 4:10 am EDT
Ross (1944) mentions that Dolophilodes (Trentonius) distinctus adults "...remarkable b/c of the production of adults during the entire year, incl. the winter months, and the wingless condition of most of the females.....records indicate the females produced during the colder months are all wingless.....Winged females have been taken during the warmer months of the year." He goes on to mention that wing presence is caused by temperature reactions influencing late larvae. Was it a really cold stream? Seems late for ambient air influences.
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Bellevue, WA

Posts: 2758
Troutnut on Jun 7, 2007June 7th, 2007, 5:04 am EDT
The stream was not unusually cold, although the previous night was.
Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist
Posts: 1
Rjs887 on Nov 22, 2007November 22nd, 2007, 1:10 pm EST
We get fantastic hatches of these on the Farmington river here in Connecticut. Two broods, summer and winter and the fish are always willing to eat the female pupa that skitters across the water. Starting in November the action gets really hot and continues through the winter till march. Colder days they come off later in the morning and can continue throughout the day, warmer days, they will come at daybreak.
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"Bear Swamp," PA

Posts: 1681
GONZO on Nov 22, 2007November 22nd, 2007, 2:41 pm EST
Hi Rich,

I've been hoping that we would eventually hear from a Farmington angler about these unusual caddisflies. Although they are quite common and widespread, it seems that nobody knows them as well or fishes them as often as the folks on the Farmington. These strange little buggers frustrated me for several seasons on the Lehigh, until I learned about the Farmington hatch and made the connection. Do you have a favorite imitation?


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