Ancient Storm

The time is 300 million years ago. We are deep in the Carboniferous period. The air is rich with the wine of oxygen. Over rich perhaps.... An arthropleurid, giant ancestral relative of the modern centipede, scurrys through a forest of primitive ferns and scale trees. Huge gosammer winged insects flit over the water.
And above the swamp a storm gathers, early lightning threatening an infernal combusion...