I can report that Mike Lawson points out this creation, to be a good looking pattern he accepted years ago only to find out it doesn't catch fish!!
Well, I don't know if I'd fully agree with that assessment, as I did catch fish with mine; but what is undeniable (at least to me) is that latex larvae certainly never proved to be superior to dubbed bodies. So, why put up with the nasty attributes?
I've found that the Czech style works best for the net-spinners (Hydropsychidae). Twisted synthetic yarn bodies get the nod in my book for free-livers (Rhyacophilidae) and some large cased caddis that abandon their shelters on occasion.
Dicosmoecus (October Caddis) is a good example of the latter. There are some favorite small creeks (that shall go unnamed) in the upper Hat Creek drainage that fish very well in the early Summer high-sticking with such patterns. Their surprisingly large native Red Bands really like 'em.
Tightly twisted yarn simulates the segmented bodies very well. The only problem is most yarns are pretty monochromatic. A neat trick is to separate the plies and incorporate a little contrasting/complimentary dubbing; really turning the yarn into a dubbing loop. The effect when twisted back up is pretty cool. My favorite for
Dicosmoecus is plain pale yellow Antron or Orlon 3 ply with a dash of hot orange and a little creamy tan Buggy Nymph. Antron yarn with the clear sparkly fibers is too much for my tastes to simulate larvae, but it would probably work fine. I experimented with brown shell backs but found they were less effective. Perhaps because they detract from the segmentation? Anyway, no need to get too anatomic with flies fished in the rock gardens.:) You go through quite a few if you're fishing them right.
Here's some photos to illustrate the result of the technique. The second photo shows the fly wet. I think the juicy looking multicolored segmentation is a real trigger. The result is quite life-like for a simple dressing. The fish seem to agree.
BTW - this fly is fairly heavy with two layers of flat lead underneath.
Hi-Stick Larva (October Caddis) #6