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.

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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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Epeorus albertae (Pink Lady) Mayfly Nymph Pictures

This specimen keys to the Epeorus albertae group of species. Of the five species in that group, the two known in Washington state are Epeorus albertae and Epeorus dulciana. Of the two, albertae has been collected in vastly more locations in Washington than dulciana, suggesting it is far more common. On that basis alone I'm tentatively putting this nymph in albertae, with the large caveat that there's no real information to rule out dulciana.

Dorsal view of a Epeorus albertae (Heptageniidae) (Pink Lady) Mayfly Nymph from the East Fork Issaquah Creek in Washington

Ventral view of a Epeorus albertae (Heptageniidae) (Pink Lady) Mayfly Nymph from the East Fork Issaquah Creek in Washington

Ruler view of a Epeorus albertae (Heptageniidae) (Pink Lady) Mayfly Nymph from the East Fork Issaquah Creek in Washington The smallest ruler marks are 1 mm.

Epeorus albertae (Heptageniidae) (Pink Lady) Mayfly Nymph from the East Fork Issaquah Creek in Washington

This mayfly was collected from the East Fork Issaquah Creek in Washington on February 18th, 2023 and added to Troutnut.com by Troutnut on February 21st, 2023.

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