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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.

Dorsal view of a Amphizoa (Amphizoidae) Beetle Larva from Sears Creek in Washington
This is the first of it's family I've seen, collected from a tiny, fishless stream in the Cascades. The three species of this genus all live in the Northwest and are predators that primarily eat stonefly nymphs Merritt R.W., Cummins, K.W., and Berg, M.B. (2019).
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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Updates from July 4, 2017

Updates from July 4, 2017

Photos by Troutnut from the South Fork Sauk River in Washington

The South Fork Sauk River in Washington
The South Fork Sauk River in Washington
The South Fork Sauk River in Washington
A westslope cutthroat, I think.
The South Fork Sauk River in Washington
The South Fork Sauk River in Washington
My wife Lena casting to a promising pool.

From the South Fork Sauk River in Washington
The South Fork Sauk River in Washington

Closeup insects by Troutnut from the South Fork Sauk River in Washington

Artistic view of a Male Epeorus deceptivus (Heptageniidae) Mayfly Dun from the South Fork Sauk River in Washington
The lack of a darkened humeral crossvein rules out Epeorus albertae and Epeorus dulciana. The lack of a dark macula on the forefemora rules out Epeorus longimanus. The small size rules out Epeorus grandis and Epeorus permagnus. That leaves as the only possibility known in Washington state Epeorus deceptivus. It is a small species, although not reportedly quite as small as this specimen. I couldn't find anything in the species description in Traver (1935) to definitively confirm or rule out the species ID, given that I don't have the preserved specimen to check under a microscope, but it has to be either deceptivus or something not yet reported in Washington.

It was collected at the same time as a similar-sized female dun.
There's a pale amber tinge to the anterior areas of the wings, which doesn't show up all that well against the blue background.

Lateral view of a Male Rhithrogena virilis (Heptageniidae) Mayfly Spinner from the South Fork Sauk River in Washington
I'm fairly sure this is a specimen of Rhithrogena virilis based on closeup examination of the reproductive anatomy under the microscope (not shown in photos). The other other species of Rhithrogena this large is Rhithrogena flavianula, but the key in Needham's Biology of Mayflies mentions annulation in the abdomen (visible in some images on bugguide.net) more distinct than that on this specimen.

The body and front wing were both about 15.5 mm long, while the cerci were 40 mm long.
Lateral view of a Female Epeorus deceptivus (Heptageniidae) Mayfly Dun from the South Fork Sauk River in Washington
I'm guessing this female is of the same species as this male dun, because they came from the same pool at the same time and the size matches, although the males and females would look very different in this case.

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