Body Light olive swannundaze (Hareline UV Mottled Galaxy Mop Chenille)
Thorax Golden olive material (Fulling Mill Tactical Microflash Dub)
Resin Clear uv resin (Solarez Bone Dry)
How to tie it
Slide a 4.6mm gold tungsten bead onto the size 10 emerger hook, seat it at the eye, then wrap eight or ten turns of.015 lead free wire behind it, push them into the back of the bead and bind them down. A mop fly's job is to get deep and stay there, so it wants weight beyond the bead alone.
Start olive Veevus 70 behind the wire and wind back to the bend, covering and tapering the wire so there is no step.
Cut a single mop finger from the Galaxy chenille about a hook gape and a half long and bind it on top of the shank at the bend with tight turns, singeing the cut end so it does not fray.
The Galaxy chenille is the point of this version: UV mottling breaks up what is otherwise a solid block of colour, giving a far more organic look than a plain mop finger.
Cover the tie-down wraps and build forward to the bead with a dubbed thorax of golden olive Tactical Microflash, kept shaggy so it blends into the mop.
Whip finish behind the bead and add a drop of Solarez Bone Dry at the mop tie-in point. That is the joint that fails first when a fish chews the fly.
Fish it deep on a euro rig or under an indicator. It imitates nothing precisely and everything vaguely, which is exactly why it works.