Reverse sides of the same fossil dragonfly larva, called scientifically Orthemis sp. (about four-fifths of an inch long), collected by Keith and Sharon Thompson sometime in 1998, from the middle Miocene Barstow Formation, Fossil Insect Canyon, Mojave Desert, California. It's approximately 17 million years old. Here's what Keith and Sharon had to say about the fossil specimen, when they posted it at a now-defunct, belly-up, fossil forum a number of years ago.

"Dorsal and ventral views of a dragonfly nymph from the Barstow Formation, California. We recovered the nymph and other arthropods (mostly pieces)from calcareous nodules created during the Miocene. The fossils were deposited in lacustrine sediments and later embedded in the nodules.
The nodules were dissolved in diluted hydrochloric acid (a 1:8) dilution leaving behind the silicified parts. We rinsed and neutralized any remaining acid, screened, dried, and examined the remaining material. This was our best find but we also found numerous parts from fairy shrimp, beetles, flies, mosquito pupa, and amazing amounts of fairy shrimp coprolites (poop). The detail on many pieces is exceptional with bristles and eyes easily recognized. Enjoy! Keith & Sharon"

A dragonfly larva called Orthemis sp., roughly 15 millimeters long (three-fifths of an inch), from the middle Miocene Barstow Formation, Fossil Insect Canyon, California. Photographer unknown.

The Barstow specimen closely resembles the living Caribbean dragonfly, Orthemis furruginea.