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.
Mayfly Species Ironodes geminatus
Physical description
Most physical descriptions on Troutnut are direct or slightly edited quotes from the original scientific sources describing or updating the species, although there may be errors in copying them to this website. Such descriptions aren't always definitive, because species often turn out to be more variable than the original describers observed. In some cases, only a single specimen was described! However, they are useful starting points.
Female Dun
Wing length: 8-9.5 mm
This species was described from male and female subimagos and a female imago. Description comparative, the species said to resemble Heptagenia sulphurea Mull. European and H. elegantula Etn., in the female sex. Vertex of head of female “‘suffused with light reddish brown, no black spots near the eyes either on the vertex or on the face, nor any at the bases of the coxae.” Wings hyaline; membrane tinted uniformly with very pale yellowish. Venation brownish black, the main longitudinal veins being amber-colored near the base. Tails whitish, not darker at joinings.
Start a Discussion of Ironodes geminatus
References
- Jacobus, L. M., Wiersema, N.A., and Webb, J.M. 2014. Identification of Far Northern and Western North American Mayfly Larvae (Insecta: Ephemeroptera), North of Mexico; Version 2. Joint Aquatic Science meeting, Portland, OR. Unpublished workshop manual. 1-176.
- Merritt R.W., Cummins, K.W., and Berg, M.B. 2019. An Introduction to the Aquatic Insects of North America (Fifth Edition). Kendall/Hunt Publishing Company.
- Needham, James G., Jay R. Traver, and Yin-Chi Hsu. 1935. The Biology of Mayflies. Comstock Publishing Company, Inc.