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.

Mount Deborah and Hess Mountains. Two of the greatest peaks of the Alaska Range rise behind the braided, glacial Susitna River. These massive mountains are 35 miles north of where I took this picture.

From the Susitna River in Alaska

Stream photos

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Skwala (Large Springfly) Stonefly Nymph Skwala (Large Springfly) Stonefly Nymph

Dorsal view of a Skwala (Perlodidae) (Large Springfly) Stonefly Nymph from the Yakima River in Washington

This Skwala nymph still has a couple months left to go before hatching, but it's still a good representative of its species, which was extremely abundant in my sample for a stonefly of this size. It's obvious why the Yakima is known for its Skwala hatch.

6 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 Cinygmula uniformis Mayfly Spinner Pictures

The identification of this specimen is not positive because some of the key characteristics conflict. The uniform amber tint of the wings and the rusty-colored mid-ventral markings on some of the abdominal sternites point to Cinygmula uniformis, but I could not locate the small ventral subapical spines on the penes that are supposed to also diagnose that species (the ones visible in the pictures aren't the ones I'm talking about). If I prioritize that characteristics, this would probably be Cinygmula mimus, but then the wing and sternite shading/markings are wrong.

Male Cinygmula uniformis (Heptageniidae) Mayfly Spinner from the South Fork Snoqualmie River in Washington

Lateral view of a Male Cinygmula uniformis (Heptageniidae) Mayfly Spinner from the South Fork Snoqualmie River in Washington

Ruler view of a Male Cinygmula uniformis (Heptageniidae) Mayfly Spinner from the South Fork Snoqualmie River in Washington The smallest ruler marks are 1 mm.

Dorsal view of a Male Cinygmula uniformis (Heptageniidae) Mayfly Spinner from the South Fork Snoqualmie River in Washington

Ventral view of a Male Cinygmula uniformis (Heptageniidae) Mayfly Spinner from the South Fork Snoqualmie River in Washington

This mayfly was collected from the South Fork Snoqualmie River in Washington on May 22nd, 2022 and added to Troutnut.com by Troutnut on May 24th, 2022.

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