Davy Wotton's
SLF Caddis Pupa

It is not a difficult fly to tie overall other than the split thread technique l use for forming the body, which is very different to the traditional manner of forming a dubbed fly body. By this means l create a fly body that shows bulk but also allows for the maximum of light to pass through the abdomen of the fly body.
 
Body colors of caddis pupa do differ and those that l would include as important are.
Insect green.
Green olive
Cream
Tan
Orange
 
Material is SLF standard dubbing
 
In almost all cases caddis pupa have a dark thoracic region and head. SLF tan to dark brown.
 
Legs are represented with two turns of hackle, shades of ginger to red brown work well, and so does hackle taken from Hungarian partridge back, and grouse.
Antenna is two fibers of Brown mallard.
 
Body sheath is Swiss straw color very light tan, straw or transparent.
 
In so far as choice of tying threads, there are only two l use. At one time it would have been Danvilles flymaster 6/0, to day we have the Wapsi Uni, and you need this in size 70 not 140 which is the thicker of the
two. Thread chosen is a color that matches the fly body.
 
Both threads allow for the split thread technique, other threads out there are corded differently and will not allow for the insertion of a dubbing needle to separate the thread and insert the dubbing to form the fly body.
I might add it is also a technique l use for many other fly patterns l use.
 
A quick review of the tying is this.
 
Run thread from behind the eye to the tail end of the fly. Select the dubbing for the body. Then split the thread and insert the dubbing into the split, close the thread and twist the bobbin to entrap the material.
Form the fly body.
Take app 1/4 ins width of the swish straw, this is set central to the upper fly body and folded equal left and right side of the fly body, which is then secured with thread.
At this point which should be app 3/5th the hook shank length wind two turns of the chosen hackle, in front of this dub a small thorax/head region of the darker chosen dubbing.
The antenna is two strands of the brown mallard tied at the head of the fly and extending twice the length of the hook shank.
Cut off the hackle fiber above the fly body, this represents the legs which are below the fly body and a integral part if the pupa's ability to swim upward to the surface.
 
A deadly fly, take my word for it.
 
Davy..

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