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.

Upper Titcomb Lake

From Titcomb Basin in Wyoming

Stream photos

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Glossosoma (Little Brown Short-horned Sedge) Caddisfly Larva Glossosoma (Little Brown Short-horned Sedge) Caddisfly Larva

Dorsal view of a Glossosoma (Glossosomatidae) (Little Brown Short-horned Sedge) Caddisfly Larva from the Yakima River in Washington

I caught this tiny larva without a case, but it seems to key pretty clearly to to Glossosomatidae. From there, the lack of sclerites on the mesonotum points to either Glossosoma or Anagapetus. Although it's difficult to see in a 2D image from the microscope, it's pretty clear in the live 3D view that the pronotum is only excised about 1/3 of its length to accommodate the forecoxa, not 2/3, which points to Glossosoma at Couplet 5 of the Key to Genera of Glossosomatidae Larvae.

11 Recently Added Photos

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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Arctopsyche grandis (Great Gray Spotted Sedge) Caddisfly Larva Pictures

At first I had trouble believing this giant Hydropsychidae larva was actually a member of its family, because of the size. I had never seen such a thing. It turned out to be a member of this exceptionally large species with a fitting name, grandis.

Ruler view of a Arctopsyche grandis (Hydropsychidae) (Great Gray Spotted Sedge) Caddisfly Larva from the East Fork Big Lost River in Idaho The smallest ruler marks are 1 mm.

Arctopsyche grandis (Hydropsychidae) (Great Gray Spotted Sedge) Caddisfly Larva from the East Fork Big Lost River in Idaho

Lateral view of a Arctopsyche grandis (Hydropsychidae) (Great Gray Spotted Sedge) Caddisfly Larva from the East Fork Big Lost River in Idaho

Dorsal view of a Arctopsyche grandis (Hydropsychidae) (Great Gray Spotted Sedge) Caddisfly Larva from the East Fork Big Lost River in Idaho

This caddisfly was collected from the East Fork Big Lost River in Idaho on August 3rd, 2020 and added to Troutnut.com by Troutnut on August 19th, 2020.

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