john_ny

It's funny that the two postings, above, (Eric's & Ja Nan's) are one after the other, because they may be related. Eric's picture looks like a hornworm; there are several, like tomato hornworm, tobacco hornworm, etc. A parasitic wasp lays eggs in the body of the catepillar. When they hatch, they chew their way out, and attach their little cocoons to the surface of the catepillar. If you Google hornworm, horned moth, hawk moth, etc., you can find lots of pictures.
I usually have some Mandevillas, in the garden, for the summer. Ocasionally, I'd get some seed pods, but not every year and, usually, not very many. Then I read that they had to be pollinated by a hawk moth. If you look at a Mandevilla flower you, right away, don't see any reproductive parts. They are way down deep in there, so you would need something with a long proboscis, or tongue, to reach them. I guess we don't have very many hawk moths around here, hence the sparcity of seed pods.

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John