I experimented with fondant first, that was completely unsuccessful. Then I though of gluing it together with caramel (since I had a fresh bag of that around too). Too messy and too hard.
Then, another light bulb went off.....cookie dough! Sugar cookie dough works perfectly (don't attempt with chocolate chip dough, the chips just get in the way and jeopardize structural integrity). It only took about 4 minutes to assemble and looked authentic.
I created the skeleton of a skeletal Lepidoptera. The Death's Head Hawkmoth (Acherontia atropos), seen in The Silence of the Lambs, has a skull marking on its back. I made a full human-like bone structure for the moth, with the grinning skull protruding from its back. The model is very thin, yet sturdy and flexible. Detail level is fantastic, and the natural texture of the 3d printing process gives it a bone-like appearance that works wonders. Yes, moths don't have endoskeletons, that's the whole point...
You can buy one in white, black, or red, for $15. More photos below, including details that show off the creepy little skull.
Here's a set of instructions for "carving" precise shapes into a pumpkin by knocking them through using a cookie-cutter and a mallet.
Place a cookie cutter on the pumpkin and tap firmly with a rubber mallet until at least half of the cutter has pierced the pumpkin's shell. (If the pumpkin shell is thin, the cutter may be pounded all the way through the shell.)
Remove the cookie cutter, using a needle-nose pliers if needed.
With a small serrated knife (or the serrated saw from a pumpkin carving kit), follow the pattern made from the cookie cutter to cut out the image, making sure to cut all the way through the shell.
TERADA MOKEI, a Japanese company, makes dense sheets of punch-out people, animals and scenery intended for use in architectural models. The sets include sports matches, mass transit, street scenes, construction sites, and an orchestra. Sounds like a fun thing to have around on general principle, for models, art projects, and entertainment value.