Split Case PMD Emerger
The Split Case PMD Emerger artificial fly is truly one of the most accurate Pale Morning Dun nymphal emerger patterns there is on the fly fishing market. I have stomach pumped many trout caught during a Pale Morning Dun mayfly hatch and found in the contents many emerging PMD’s that look just like the picture above. On the Owyhee River at the Oregon and Idaho border the PMD mayfly is the dominant mayfly for all of summer. While on the Owyhee River I might visit with a few anglers I know during the day and you can bet your next month’s mortgage payment that they have Split Case PMD Emergers in their fly boxes. On the Owhyee River, over the course of the last five or six years, the Split Case PMD Emerger was far and above the most effective fly for catching large brown trout.
When the PMD nymph leaves the bottom of the river to swim to the surface to become a winged adult it arrives at the meniscus (surface film or tension) where it is stopped. At this point the nymph is no longer a nymph but an emerger, but it still looks like the PMD nymph. It is at this point in the emergence that the adult dun inside the emerger starts to break out of its nymphal shuck. This break out takes on the form of a split down the middle of the back where the adult dun will crawl out and emerge onto the surface. On the Split Case PMD Emerger that little yellow mark on top of the thorax is representing this phenomenon. The PMD is a little yellow mayfly and that bright yellow marker on the Split Case Emerger imitates this. This imitates the real PMD nymphal emerger to perfection.
When you identify trout feeding during a PMD hatch just under the surface you are seeing trout eating the nymphal PMD emerger and to best represent this tie on a Split Case PMD Emerger and your results will surprise you. The Split Case PMD Emerger is also the perfect pattern to nymph fish before or after a PMD hatch. It’s an imitative nymph that can be a game changer for you while waiting for the hatch to begin.