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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.

> The Foss River

Landscape & scenery photos from the Foss River

Closeup insects by Troutnut from the Foss River in Washington

Male Doroneuria baumanni (Golden Stone) Stonefly Adult
I found this stonefly on some streamside vegetation. I didn't see any in the air in several hours of fishing.
Ephemerella aurivillii  Mayfly Nymph
This is a puzzling one to identify and I'm not sure about the species. The maxillary palp is present and segmented, and the maxillary canines are not strongly serrate laterally. I think it's Ephemerella, not Serratella. The ventral lamellae of the gills on abdominal segment 6 have a clear median notch with a depth at least half the length of the lamellae, which points toward a couple of uncommon species (most likely Ephemerella alleni), but the abdominal tubercles and coloration don't fit that species. To add to the confusion, none of the above species are expected to emerge in the fall, as far as I know. I'm going to call this one Ephemerella aurivillii for now, but that's highly uncertain.
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