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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Perlodidae (Springflies and Yellow Stones) Stonefly Nymph Perlodidae (Springflies and Yellow Stones) Stonefly Nymph

Artistic view of a Perlodidae (Springflies and Yellow Stones) Stonefly Nymph from the Yakima River in Washington

This one seems to lead to Couplet 35 of the Key to Genera of Perlodidae Nymphs and the genus Isoperla, but I'm skeptical that's correct based on the general look. I need to get it under the microscope to review several choices in the key, and it'll probably end up a different Perlodidae.

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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Male Acerpenna pygmaea (Tiny Blue-Winged Olive) Mayfly Spinner Pictures

Lateral view of a Male Acerpenna pygmaea (Baetidae) (Tiny Blue-Winged Olive) Mayfly Spinner from the Henry's Fork of the Snake River in Idaho

Male Acerpenna pygmaea (Baetidae) (Tiny Blue-Winged Olive) Mayfly Spinner from the Henry's Fork of the Snake River in Idaho

Dorsal view of a Male Acerpenna pygmaea (Baetidae) (Tiny Blue-Winged Olive) Mayfly Spinner from the Henry's Fork of the Snake River in Idaho

Artistic view of a Male Acerpenna pygmaea (Baetidae) (Tiny Blue-Winged Olive) Mayfly Spinner from the Henry's Fork of the Snake River in Idaho

Ventral view of a Male Acerpenna pygmaea (Baetidae) (Tiny Blue-Winged Olive) Mayfly Spinner from the Henry's Fork of the Snake River in Idaho

Ruler view of a Male Acerpenna pygmaea (Baetidae) (Tiny Blue-Winged Olive) Mayfly Spinner from the Henry's Fork of the Snake River in Idaho The smallest ruler marks are 1 mm.

This mayfly was collected from the Henry's Fork of the Snake River in Idaho on August 1st, 2020 and added to Troutnut.com by Troutnut on August 18th, 2020.

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