|Size 14 Thorax Dun mayfly imitation.|
This fly is called a Thorax Dun, and it can be tied in whatever color and size you need to imitate your local mayflies. In class I always teach it in a size 14, and usually in some kind of color combo that imitates a Sulphur or a Hendrickson mayfly. Or sometimes we tie it with a gray body and grizzly colored hackle, a sort of poor man's Adams, I guess you could say.
If you wanted to get fancy, you could make the wings out of turkey flats or some other feather, but I like to use Antron yarn, because it's easier to use and it has a nice shimmer. Perhaps some day the DuPont family will recognize me for all the times I have extolled the virtues of their synthetic yarns during my Joy of Fly Tying classes and lavish me with riches beyond my dreams... I won't hold my breath.
I now present to you the Thorax Dun, in video form:
Thorax Dun Pattern Recipe
Hook: Tiemco 100 or any other standard dry fly, size 10-22
Thread: 8/0 to match the body color
Tails: Dun or cream colored Mayfly Tails
Body: Superfine dubbing, color to match the natural
Wing: Antron yarn, looped straight up underneath the hook
Hackle: Rooster, sized for the hook, in ginger, dun, or grizzly