Spring this is a time when first bigger mayflies will appear and in that time I like to use a emerger type of flies. In many situations, when the dry fly is not so effective, it is easier to tempt the trout using fly under the surface, using the emerger.
For tying emerger's bodies I prefer to use the antron, which is in my opinion the best fly tying material for that patterns. Very fine, delicately shimmering and transparent fibers this is all what we need. Ribbing by a thin pearl tinsel will additionally brighten the fly.
Hook: Fmfly 706 no. 14
Thread: UNI 8/0 Brown
Body: Wapsi Antron Dubbing Golden Olive + UNI Pearl #16
Gills: hare mask dubbing
Wing case/mini wing: natural CdC