That's a killer looking nymph! Very very fishy. This may be redundant, but make sure you tie up a variety of czech nymphs in various size/weights and color variations/hotspots so you can accommodate a variety of water types and feeding cycles. Many times Czech or Euro Nymphing is less about the dressing and more about how the presents in a "team".
I think I'm going to go tie a handful of those right now.