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.
Jason, as noted before the photos of the ventral side, from the fish's eye view are great. These Show the lighter edges of the segments that Gonzo often imitates with lighter thread. I've been tying some of my baetids and paraleps with a unithread body ribbed with a lighter color (twisted to make the rib thin) and the trout seem to like it. I sometimes, (when I remember) add a coat of thinned flexament, which preserves the true thread color when it gets wet. I'd be curious to hear others ideas about Blue Quill imitations. A parachute has been working as well as Gonzo's upside down comparadun tie, one of which was readily gobbled (and seated in the lip on the hookset) by a nice spring creek brown as I hit the tail end of the hatch after a day of nymphing yesterday.