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.
I confirmed the identity of this nymph by looking at it under a microscope to be certain of the shape of its gills and head.
This mayfly was collected from unknown in Wisconsin on January 31st, 2004 and added to Troutnut.com by Troutnut on January 25th, 2006.