Opabinia is quite unlike any animal on our planet today. It had five compound eyes (each mounted on a short stalk), a frontal “nozzle” or proboscis, a body with repeated lobes and gills, and a prominent tail fan. Body length ranged between 4.3 and 7.0 cm - excluding the proboscis, which was four times longer than its head.
Opabinia was a swimmer. Rippling waves along its lobes propelled it forward, while it used its tail fan to steer or maintain stability. The proboscis was highly flexible, ending with two opposing claws each with five or six spines. Opabinia was likely a carnivore and used the claws on its proboscis to grasp soft food items and carry them towards its mouth, which was located under the base of the proboscis.