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 mature nymph is associated with the dun from the same location and date posted on this hatch page. Size 10mm.
This mayfly was collected from the Fall River in California on November 12th, 2011 and added to Troutnut.com by Entoman on December 15th, 2011.