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

Blue-winged Olives
Baetis

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.

Middle Fork Snoqualmie

From the Middle Fork Snoqualmie River in Washington

Stream photos

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Limnephilus (Summer Flier Sedge) Caddisfly Larva Limnephilus (Summer Flier Sedge) Caddisfly Larva

Case view of a Limnephilus (Limnephilidae) (Summer Flier Sedge) Caddisfly Larva from the Yakima River in Washington

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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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Female Helicopsyche borealis (Speckled Peter) Caddisfly Adult Pictures

This one keys pretty easily to the Helicopsychidae family, of which there is only one genus in North America, and one species reported in this general area.

Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho

Ventral view of a Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho

Dorsal view of a Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho

Lateral view of a Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho

Ruler view of a Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho The smallest ruler marks are 1 mm.

The large warts on the back of the head, between the eyes, are partly diagnostic of this family.

Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho

Ventral view of the terminalia.

Female Helicopsyche borealis (Helicopsychidae) (Speckled Peter) Caddisfly Adult from the Henry's Fork of the Snake River in Idaho

This caddisfly was collected from the Henry's Fork of the Snake River in Idaho on July 31st, 2020 and added to Troutnut.com by Troutnut on August 17th, 2020.

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