The Olive Sparkle Pupa Emerger Fly is the result of closely observing hatching caddis flies in underwater environments. It is an unconventional but effective fish catcher. The antron case is supposed to imitate the gas bubbles used by hatching flies to propel them to the surface. Whether or not this is accurate trout seem to inhale this fly when caddis are hatching. It can be fished with a dead drift, twitched, or swung. Different colors and sizes allow the angler to match the local caddisflies.