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 collected at the same time as this male and is likely the same species.
This mayfly was collected from the Madison River in Montana on July 1st, 2019 and added to Troutnut.com by Troutnut on July 17th, 2019.