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3. Pupal exuvia pics

Here are a couple pics of a caddis pharate adult separated, but within, the pupal skin. The pupae was removed from the closed pupal case. In the photo of the abdomen you can see the wing pad and it is not completely darkened so this "pupae" was not quite ready to leave the case yet.

Thanks for posting these.

Cool. This somewhat confirms the ideas behind the LaFontaine caddis and similar halo patterns.

I'm not convinced of that -yet.

somewhat? :)

I think the difference may be just semantics. When LaFontaine discusses the "bubble" look, he is clearly referring to the reflective or translucent character of the separated cuticle. Use of the word does open up the possibility for misinterpretation as a gas bubble encased in water pressure is undoubtedly more reflective than either gas or molting fluid encased in a cuticle. If memory serves, these subtleties are not addressed in his writings, and it certainly doesn't help by attaching adjectives like "bright" and "shiny", either.:) What is undeniable is that there is a big difference between the look of a diving egg layer and an ascending pupa in terms of brightness. Personally, I wouldn't describe a pupa as looking like a bright or shiny bubble.

If you look at pharate pupae (look at all the images you can find) you'll see that the largest amount of excess skin is around the abdomen, and at at the very tip is a bag of skin. If a gas was forced into this skin, wouldn't the insect buoy up abdomen first? There is comparatively little loose skin up front. And the abdomen, where the rete (gills in larvae/spiracules in adults) is located, would seem to be the most likely place for gas production.

Gills appear to be intact -Not dessicated.