There's a whole period in the evolution of modern insects that's pretty much a blank, thanks to a gaping hole in the fossil records. The so called Hexapoda Gap runs from 385 million years ago to 325 million years ago. It's right around when the insect world changed from the old, wingless insects to the incredible diversity of the modern species — and it's a period that we don't know much about. A new fossil discovered in Belgium might just plug some of that gap, and show the origins of the flying bugs we know and love.
The fossil is described in this week's Nature, and has been dubbed Strudiella devonica. Dated to the Late Devonian, around 370 million years ago, this 8mm long fossil has a "six-legged thorax, long single-branched antennae, triangular jaws and a 10-segmented abdomen," all features that would push it into the context of an insect — and possibly the oldest complete insect fossil ever discovered.
While this specimen itself was wingless, a number of features seem to suggest that by this point species had already started to diversify, and the incredible breadth of insects had started to arise — significantly earlier than the 325 million years ago that most flying insect fossils start to crop up. In fact, while this fossil itself doesn't have wings, it may just be a nymph, and could even have had wings as an adult.
There's still a huge amount we don't know about the evolution of insects, thanks to an incredibly patchy fossil record. But discoveries like this put us well on the way to understanding how they grew wings and took to the skies.