This is an anomalocaridid – a really big, really old shrimp-like critter – named Laggania cambria. These were as big as it got in the Cambrian period, an age before the dinosaurs, when life flourished in warm, shallow seas.
Recently, paleontologists found that Laggania – which was around half a meter long and about 500 million years old – was actually kind of small and young compared to some of its cousins, which grew to 6 feet long over 550 million years ago. They were the apex predator of their day – the monster everything else was afraid of.
I think I’d probably be a little nervous, too.
This likeness is a life-size model that’s currently on display in the Staatliches Museum für Naturkunde Karlsruhe, Germany.
[Image from Wikipedia.]