This fossil was found in the sandstones of southern Massachusetts, and is the oldest known full-body impression of a flying bug. It's there on the left, and you can see the distinct impressions made by its six legs, as it struggled to escape from the mud it got stuck in before being fossilized. Formed approximately 300 million years ago, this cast is the most ancient evidence of the Pterygota subclass of insects, and is thought to be the distant antecedent of the mayfly.

Thankfully, it's not the enormous insect of television legend, measuring a relatively un-terrifying 36mm in length.