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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.
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Tiny Winter Blacks

Like most common names,"Tiny Winter Black" can refer to more than one taxon. They're previewed below, along with 5 specimens. For more detail click through to the scientific names.

Stonefly Family Capniidae

These are sometimes called Tiny Winter Blacks.
These are the first stoneflies of the year to appear in most parts of the country, and often the first aquatic insects noticed by the angler. Their dark brown or black bodies are easy to spot against the snowbanks where they crawl around.

Capnia in the West and Allocapnia in the East are probably the most common genera of this prolific family.
Capnia nana (Capniidae) (Little Snowfly) Stonefly Adult from the N. Fork Touchet River in Washington
Dorsal view of a Capniidae (Snowfly) Stonefly Nymph from Cascadilla Creek in New York

Stonefly Family Leuctridae

These are sometimes called Tiny Winter Blacks.
Leuctra is the only genus of any known importance to trout anglers. Their wings are rolled to a needle-like point; hence the common name, needle flies.
Megaleuctra stigmata (Leuctridae) (Little Black Needlefly) Stonefly Adult from Talking Water Creek in Montana
This is one of rarest stoneflies in western Montana. It is a bit unusual that it is fairly abundant in a handful of streams that empty into the east side of Flathead Lake. A very beautiful bug.

Stonefly Family Nemouridae

These are sometimes called Tiny Winter Blacks.
Lateral view of a Female Amphinemura (Nemouridae) (Tiny Winter Black) Stonefly Adult from Mystery Creek #23 in New York
A few of these tiny stoneflies were among the only species of aquatic insect adults in the air on this particular afternoon, with most of the action coming from a species of Epeorus mayfly. I somehow forgot to photograph this one on the usual ruler, but I recall it was very, very small, with an abdomen no more than 1mm in girth and the body, not counting the wings, probably just 5-7mm long.
Dorsal view of a Prostoia (Nemouridae) (Tiny Winter Black) Stonefly Nymph from Salmon Creek in New York

Tiny Winter Blacks

Scientific Names
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