Mercer’s Missing Link

Mercer’s Missing Link, Little Yellow May

Show

Tying Instructions

1. Pinch the barb of the hook with the tips of your vise.

2. Attach the thread just beyond the 1/3 position of the hook shank.

3. Attach a strand of Pearl Krystalflash to the top of the hook shank with some thread wraps.

4. Wrap the Krystalflash down to the hook bend with touching wraps. We want to the the abdomen show a natural curve. A position just before reaching the midpoint of the bend works well. Flattening the thread will also help.

5. Wrap the thread back up to the 1/3 position on the hook shank and build a light taper of thread from the bend of the hook to the 1/3 position.

6. Spiral wrap the ribbing forward to the 1/3 position. Note that the spirals get wider as you approach the thorax region.

7. Coat the ribbed thread abdomen with some fly finish. I am using Loons Clear Fly Finish Flow, a UV activated coating.

8. Use a UV lamp to harden the coating. This will protect both the ribbing and the thread abdomen from getting nicked and unraveling.

9. Apply some ice dubbing to the thread at the 1/3 position of the hook shank.

10. Create a small ball of dubbing at the 1/3 position. This represents the thorax and also helps separate the spent wings of the pattern.

11. Separate about 10-12 strands of Z-lon from the yarn. You don’t need much to represent the spent wings.

12. Secure the middle of the Z-lon strands to the top of the hook shank just in front of the ice dubbing ball. Direct the strands downward with your fingers and secure the strands with thread wraps to maintain the downward projectory of the strands.

13. Clip a section of Coastal Deer Hair from the hide and clean off the underfur. Place the hair into a stacker. Note all of the unequal lengths of the hair.

14. Even the tips and have the tips facing the rear of the hook.

15. Measure the tips so that they are about the same length as the hook shank.

16. Attach the deer hair with two tight wraps at the 1/3 position, lifting upwards with the thread to keep the hair on the top of the shank. Then wrap a small band of thread forward toward the eye of the hook.

17. Lift up on the tag ends of the hair and trim just above the eye of the hook.

18. Attach a sized saddle hackle to the side of the thread band at the base of the hackle.

19. Wrap the saddle hackle around the base of the wing and the trimmed hairs representing the head, twice. Secure the hackle against the bottom of the hook shank just behind the eye with three tight thread wraps.

20. Secure the thread with a few half hitches.

21. Trim the Z-lon spent wings at the end of the hook bend. Also trim off any errant hackle fibers around the head.

22. The finished Missing Link, Little Yellow May.

Materials to Order Material, click the link
Hook	TMC 102Y #11-15
Thread	Uni-thread Light Cahill 8/0
Body	Uni-thread Light Cahill 8/0
Thorax	Hot Yellow Ice Dubbing
Ribbing	Pearl Krystalflash
Wing	Yearling Elk Hair, Bleached
Downwing	Ginger Kinky Z-lon
Hackle	Dun Saddle Hackle

Mike Mercer

Mercer’s Missing Link

This pattern was designed by Mike Mercer, in 2010, originally for caddis hatches. However, the design was also very effective on other hatches, such as Mayflies and Stoneflies, by modifying both coloration and size of hook. Mike called the pattern, Missing Link, since it seemed to solve the mysteries of how a fly pattern can be quite effective on one day and totally ineffective on another.

Despite designing the pattern specifically for the caddis hatch, the principals of the pattern can be applied to any insect that is molting into a dun at the surface of a stream or lake and encounters difficulty. From the fish perspective, this difficulty in the transformation could look like a real mess rather than the silhouette of a complete nymph or dun and this “mess” might be exactly what the fish are looking for on a given day. The “mess” occurs when the transformation fails and the insect dies from drowning. It’s a meaty meal for the fish with very little effort needed to take it.

Nymphal Transition

The body of the pattern is meant to be thin and weak from the transition of a nymph to a dun. To achieve this look, Mike decided to use a simple thread body as seen on many mayfly patterns. He would add a strand of flashabou to represent the trapped gases that the nymphal case would have and protect both the thread and the flash with a coating of Softex or Loon’s UV Clear Fly Finish, Flow. The pattern needed a downwing profile that was both frail and translucent. A sparse number of Z-lon or Antron fibers could achieve this look if the strands were separated by a small clump of dubbing on the hook shank.

Finally, the pattern need floatation that would achieve a low riding profile. Ralph Cutter had a solution to this with his E/C caddis pattern where the Elk Hair was a wingpost with a parachute hackle at it’s base and Mike incorporated that feature into the Missing Link pattern. The hook that Mike prefers is the TMC 102Y, which is a wide gap dry fly hook similar to the TMC 100. The wider gap is an advantage when tying parachute patterns and allows the thread body to extend down the bend of the hook. The hook wire is 1X fine which is subject to bending with large fish, so some turn to a TMC 100sp-bl for a heavier wire.

Mercer’s Missing Link, Baetis

Hook	TMC 102Y #17-19
Thread	Uni-thread Olive 8/0
Body	Uni-thread Olive 8/0
Thorax	Black Peacock Ice Dubbing
Ribbing	Pearl Krystalflash
Wing	Natural Yearling Elk Hair
Downwing	Dark Dun Z-lon
Hackle	Dun Saddle Hackle

Mercer’s Missing Link, PMD

Hook	TMC 102Y #15-17
Thread	Uni-thread Brown 8/0
Body	Uni-thread Brown 8/0
Thorax	Peacock Ice Dubbing
Ribbing	Pearl Krystalflash
Wing	Yearling Elk Hair, Bleached
Downwing	Medium Dun Z-lon
Hackle	Dun Saddle Hackle

Mercer’s Missing Link, Green Drake

Hook	TMC 102Y #11-15
Thread	Uni-thread Olive Dun 8/0
Body	Uni-thread Olive Dun 8/0
Thorax	Peacock Ice Dubbing
Ribbing	Pearl Krystalflash
Wing	Yearling Elk Hair, Bleached
Downwing	Cream Z-lon
Hackle	Dun Saddle Hackle