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Blue-winged Olives

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.

Male Callibaetis pallidus (Speckled Dun) Mayfly Spinner Pictures

This specimen keys to Callibaetis pallidus using the key in Needham et al (1935) based on the wing venation: numerous crossveins in the forewing behind the fourth longitudinal vein, paired marginal intercalaries in the middle area of the fore wing, longitudinal veins largely light rather than black and white banded, and wing wholly pale.

This mayfly was collected from the Teal River in Wisconsin on June 10th, 2021 and added to Troutnut.com by Troutnut on June 11th, 2021.

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  • Needham, James G., Jay R. Traver, and Yin-Chi Hsu. 1935. The Biology of Mayflies. Comstock Publishing Company, Inc.
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