Perspicaris
Perspicaris is a fossil arthropod from the Cambrian period. It was long and bivalved. The valves, encasing the thorax, were joined together by a dorsal hinge.
It is difficult to establish the lifestyle of Perspicaris. Its large eyes and other parts would suggest a swimming animal, yet it lacks claws, which seems to suggest a bottom feeder.
Two species of Perspicaris are found in the famous Burgess Shale in British Columbia, Canada.
