The Pheasant Tail Nymph is one of the most ubiquitous nymphs there is. Its dark brown color is useful for hundreds of mayfly species all of which are similar in their nymphal stage. This is one fly pattern you should have in all sizes. The great thing about this fly pattern is the addition of the tungsten bead that gets it down in a hurry to the feeding zone. For those who like to fish multiple mayfly nymph fly patterns, these are winners. The flash replicated a bubble forming as the wings develop and the nymph lives underwater.