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.
Based on the pale longitudinal forewing veins (excepting the costals), dark middle terga, and genitalia (Burks '53), this specimen is P. adoptiva.
This mayfly was collected from Factory Brook in New York on May 9th, 2007 and added to Troutnut.com by Troutnut on May 18th, 2007.