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.

Stream photos

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Clostoeca disjuncta (Northern Caddisfly) Caddisfly Larva Clostoeca disjuncta (Northern Caddisfly) Caddisfly Larva

Lateral view of a Clostoeca disjuncta (Limnephilidae) (Northern Caddisfly) Caddisfly Larva from the Yakima River in Washington

This one was surprisingly straightforward to identify. The lack of a sclerite at the base of the lateral hump narrows the field quite a bit, and the other options followed fairly obvious characteristics to Clostoeca, which only has one species, Clostoeca disjuncta.

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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Ameletus (Brown Dun) Mayfly Nymph Pictures

Ventral view of a Ameletus (Ameletidae) (Brown Dun) Mayfly Nymph from the South Fork Snoqualmie River in Washington

Ameletus (Ameletidae) (Brown Dun) Mayfly Nymph from the South Fork Snoqualmie River in Washington

Dorsal view of a Ameletus (Ameletidae) (Brown Dun) Mayfly Nymph from the South Fork Snoqualmie River in Washington

Ruler view of a Ameletus (Ameletidae) (Brown Dun) Mayfly Nymph from the South Fork Snoqualmie River in Washington The smallest ruler marks are 1 mm.

Lateral view of a Ameletus (Ameletidae) (Brown Dun) Mayfly Nymph from the South Fork Snoqualmie River in Washington

This mayfly was collected from the South Fork Snoqualmie River in Washington on June 13th, 2019 and added to Troutnut.com by Troutnut on June 14th, 2019.

Discussions of this Nymph

Siphlonurus sp.

1 replies

Posted by Millcreek on Jan 27, 2020

Last reply on Feb 2, 2020 by Troutnut

This looks more like an Ameletus species than a Siphlonurus species. At any rate it isn't Siphlonurus because it dosen't have double gills on any segments.

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