SIMPLE AND EASY FLIES- Mid Depth Pupa (TanThread Midge)
In the March 1989 issue of Fly Fisherman magazine is an article called “The Mighty Midge Pupa” written by Eleanor I Schaeffers (she and her husband “Dutch” owned Terminal Tactics, a now defunct company that used to make a complete line of tippets and accessories). One of the patterns that caught my eye was the “Middepth Pupa”. It is really just a simple thread midge that has given me great success on many rivers in the Rocky Mountain west. I like simple and easy flies, and this one is all of that.
I tied up a few dozen in assorted colors for our annual Trout Unlimited chapter spring trip to the Bighorn River in Montana. Our usual migration from Cottonwood Camp to beautiful downtown Fort Smith is a short but necessary one to pick up supplies for the days float and for buying a fishing license to be legal. A required visit to the fly shops to check out the hot flies. You can usually tell which ones they are since there’s only a couple or so left in the bins. After everybody was filled with fly shop trinkets and licenses, it’s off to the afterbay boat launch to our waiting flotilla of rented drift boats.
Back then the hot flies were an orange Bighorn scud; Pheasant tail nymphs, orange slickers and San Juan worms. Heading down river from the boat ramp we would hook and land a few trout as we made our way to our first destination behind the first island commonly called the “meat hole”. This is usually a very productive area for large rainbows. After a few hours of fishing this area our boat decided to move on to the next area we wanted to fish, a place called “split island”.
After beaching the drift boat at the island, it was time for lunch, which was the usual fare, nothing exotic. Our next order of business was to decipher the current coming in from the main channel of the river and a back channel behind the island. Once figured out, I decided it was time to use one of the “Mid depth pupas” I tied up for this trip. I tied on a tan colored “Mid depth pupa” (I call it a thread midge), crimped on a small split shot about 18 inches above the fly and had one of the best days on the Bighorn river that I’ve ever had. There were fish after fish just wanting to be hooked. Even some of the members fishing with me were amazed at all of the fish I was hooking and releasing.
Since that spring trip to the Bighorn River, that fly pattern has proven itself all over the rocky mountain area. So its time to tie the pattern, and it’s really easy to tie and does not require complicated tying steps.

Materials:
- Hook: Tiemco 101 Size 16
- Thread: Hook & Hackle Brand 8/0 Tan
- Rib: Thread colored with black marker
- Body and head: Tan thread
(See Tying Notes)
Mid Depth Pupa (Tan thread midge)
Step 1: Tie on thread behind the eye and wrap thread in touching turns to the bend of the hook. Leave a short tag of thread at the bend; this will be used for the rib.
Step 2. With a permanent marker, color the tag of thread.
Step 3. Using the tying thread, build a body. I like to use 4 layers of tying thread to do this. How many you use is entirely up to you. After wrapping the body, spiral wrap the ribbing thread forward and secure.
Step 4. Wrap a small bulbous head, whip finis and apply head cement, if you desire.
Tying Notes
- Use any style hook
- Tie this pattern in any size
- Tie this pattern in any color
- Use anything you want for the ribbing (thread, wire, Krystal flash etc)
- Use any size thread (3/0, 6/0, 8/0 or any denier)
- Use whatever colored bead
- Use 2 beads
- You can taper the body if you want it tapered
- Add a wing of Krystal flash, Zlon etc
- Coat the entire fly using the latest UV cured adhesives
- Use a darker thread for the head (colored with permanent marker)
- Add breathers for a chironomid
VARIATIONS
Different Hooks
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Different Beads
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The above fly is tied on a Daiichi 1250 size 12 hook, has 2 beads (gunmetal and mercury) and a slightly tapered body that is coated with Clear Cure Goo UV adhesive
Different Colors
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Chironomid
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Beginning Fly Tying | Intermediate Fly Tying | Advanced Fly Tying.