» Genus Baetis (Blue-Winged Olives)
17 species aren't included.
This is page 4 of specimens of Baetis. Visit the main Baetis page for:
- The behavior and habitat of Baetis.
Pictures of 32 Mayfly Specimens in the Genus Baetis:
Female Baetis tricaudatus (Blue-Winged Olive) Mayfly Nymph
View 13 PicturesThese nymphs were highly abundant in my early April kick net samples from the Yakima Canyon, and one of them emerged into a dun, which I photographed immediately. Similar-looking nymphs but with distinctly brighter color patterns were also abundant. I just photographed one. After extensive views under the microscope, it's clear the bright ones are males and the dull ones are females of the same species.
The most likely guess at the species is Baetis tricaudatus, which may be a complex of related species that haven't all been sorted out yet. It isn't a perfect fit to every key characteristic (and I never seem to find a Baetis that matches the expected pronotum (Pronotum: The top of the insect prothorax.) color patterns, but that seems to be the closest.
The microscope images here were taken with different specimens from the main photos (so I could dissect them while preserving that one intact), but clearly the same species.