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 specimen is certainly Nyctiophylax and most likely Nyctiophylax affinis. I don't know my caddisfly parts well enough to definitively follow the Nyctiophylax key in Morse (1972), but that source states that affinis is the predominant Midwestern species, being widespread and common in the region where I found this one. The anatomy of this one seems to match those at least as well as the other two potential options based on range, Nyctiophylax uncus and Nyctiophylax banksi.
This caddisfly was collected from the Teal River in Wisconsin on June 8th, 2021 and added to Troutnut.com by Troutnut on June 9th, 2021.