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.
This one was surprisingly straightforward to identify. The lack of a sclerite at the base of the lateral hump narrows the field quite a bit, and the other options followed fairly obvious characteristics to Clostoeca, which only has one species, Clostoeca disjuncta.
Millcreek on Jun 9, 2017June 9th, 2017, 4:35 pm EDT
These nymphs are common in the Russian River. Suwallia nymphs are usually found in tail-outs of rapids at depths of about 6 inches on a gravel bottom. They measure 10-13 mm not including the cerci and antennae. The nymphs are found from early March to July.
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