Split Case PMD

Imitates emerging Pale Morning Dun; split wingcase shows nymph shedding shuck.

Printed on the 4 of clubs

Most emerger patterns suggest a stage; the Split Case shows a moment. A dark, glossy wingcase is tied so it splits open along the top, revealing pale fibres pushing out beneath — exactly what happens as a Pale Morning Dun tears its nymphal skin and starts to climb out. It is one of the more literal imitations in a fly box, and it works.

During a PMD hatch, a large share of the insects are stuck in this state, hanging half-out and going nowhere. Trout learn quickly that these cannot escape, and they will often eat nothing else while the hatch is on. Anglers fishing a clean dun into that situation get refused all afternoon.

It is fished just under or in the film rather than deep. That is the zone where the naturals are trapped, and being a few inches too low is enough to be ignored.

What does a Split Case PMD imitate?

Pale Morning Duns caught in the act of emerging.

How do you fish a Split Case PMD?

Fish it in or just under the surface film, dead drift, on fine tippet. Trailing it eighteen inches behind a visible dry solves the problem of tracking it.

When should you fish a Split Case PMD?

Summer PMD hatches, especially mid-hatch when fish stop taking clean duns but keep working.

What are the quick tips for fishing it?

• If fish are bulging rather than nosing, this is the fly.
• Grease the leader, not the fly.
• Trail it behind a Parachute Adams so you can see where it is.

How is a Split Case PMD tied?

• Hook: curved emerger hook, #16-#20
• Shuck: brown Z-lon
• Body: pale morning dun dubbing
• Wingcase: black Thin Skin, split
• Thorax: pale dubbing

Dressings vary by tier and region. Treat this as the common recipe, not the only one.