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.
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.
Litobrancha on Jun 4, 2007June 4th, 2007, 11:47 am EDT
pretty sure this psilotreta, possibly labida. frontalis has big puffy head warts that pop out and hairy maxillary palps. some of the other species are lighter colored.