The creatures, known as anomalocaridids, were already thought to be the largest animals of the Cambrian period.
The period was known for the “Cambrian Explosion” that saw the sudden appearance of all the major animal groups and the establishment of complex ecosystems about 540 to 500 million years ago.
Scientists previously thought that the animals—which had long spiny head limbs presumably used to snag worms and other prey, and a circlet of plates around the mouth—grew to be about two feet long and died out at the end of the Cambrian.
Researchers have since discovered a giant fossilized anomalocaridid that measures one meter (more than three feet) in length with a series of blade-like filaments in each segment across the animal’s back, which may have functioned as gills.
Read it all here at futurity